Effect on Body Composition of Protein Supplementation During the First Six Months After Bariatric Surgery

Effect on Body Composition of Protein Supplementation During the First Six Months After Bariatric Surgery | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Effect on Body Composition of Protein Supplementation During the First Six Months After Bariatric Surgery Beatriz Ramos, Juan José López Gómez, David Primo Martín, Rebeca Jimenéz Sahagún, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7951468/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Introduction: Progressive diets after metabolic and bariatric surgery that are restricted in protein, protein intolerance, and malabsorption from techniques that exclude the duodenum result in nearly half of patients not consuming the recommended protein intake after surgery. Methods A cohort study was designed with 181 patients who underwent sleeve gastrectomy, gastric bypass, and biliopancreatic diversion. Eighty-eight patients (prospective cohort) received a progressive diet with a normocaloric, high-protein oral nutritional supplement during the first two weeks after surgery (817 kcal, 65.7 g protein/day). A historical cohort of 93 patients treated with a standard progressive diet (217 kcal, 11.7 g protein/day). Anthropometric and body composition data were analyzed before surgery, and at 1 and 6 months post-surgery. Results percentage of weight loss was observed in patients on the low-protein diet (LPD) at one month (LPD 13.44% (6.71%) vs. high-protein diet (HPD) 10.78% (4.45%); p < 0.01) and at six months (LPD 22.89% (8.78%) vs.HPD 19.49% (7.01%); p < 0.01). There was maintenance of lean mass index (LPD − 1.37 (0.69) kg vs.HPD + 0.31 (0.79) kg; p = 0.01) in HPD patients at one month, with no differences in fat mass loss. At six months, there was less loss of lean mass index (LPD − 2.75 (2.01) kg vs.HPD − 1.24 (2.06) kg; p = 0.00) and phase angle (LPD − 1.25 (51.77) kg vs. HPD + 0.83 (0.12) kg; p = 0.01) in HPD patients. Conclusions Patients on HPD showed maintenance of lean mass index and phase angle compared to those on LPD during the first six months after bariatric surgery. metabolic and bariatric surgery protein supplementation high-protein diet body composition Figures Figure 1 Figure 2 Figure 3 Figure 4 Key Points Introduction The prevalence of overweight and obesity has increased in recent decades worldwide and across all age groups, including children and adolescents ( 1 ). Metabolic and bariatric surgery (MBS) is a treatment option for individuals with obesity who do not achieve sufficient weight loss with lifestyle measures and medications. It is also the only treatment option that has demonstrated long-term weight loss maintenance ( 2 ). MBS techniques can be divided into restrictive or mixed/malabsorptive. Although the most widely used technique globally is gastric bypass (GB) ( 3 ), there is currently a growing trend toward restrictive procedures( 4 ). Nutritional deficiencies are the most frequent complication after MBS, secondary to modifications of the gastrointestinal tract, progressive diets, and reduced gastric reservoir, leading to dietary restriction and malabsorption ( 5 ). The progressive diet is based on a gradual modification of food volumes and textures until tolerance of a balanced diet is achieved. In the first weeks after surgery, the liquid diet, based on water, infusions, or clear broths, rarely meets the minimum protein recommendations of 60 g/day ( 6 ). This protein deficit in the early weeks after surgery can lead to loss of fat-free mass and affect patient functionality ( 7 ). Protein deficiency is the most common macronutrient deficiency after MBS ( 8 ). It is more prevalent in patients undergoing mixed/malabsorptive techniques such as biliopancreatic diversion (BPD) or GB. It is estimated that between 7–21% of patients with BPD present with protein malnutrition due to maldigestion and absorption secondary to altered biliary and pancreatic function ( 9 ). In GB patients, protein malnutrition is found in 13% after two years, especially if the alimentary limb is longer than 150 cm, or 5% if shorter ( 9 ). In restrictive techniques, protein malnutrition can occur if protein sources are avoided for prolonged periods, with frequent vomiting or diarrhea, food intolerances, or alcoholism( 10 ). Protein supplementation after MBS emerges as an option to prevent protein malnutrition and its consequences. The main objective of this study is to evaluate the effect of early oral protein supplementation after surgery on body composition up to six months postoperatively, compared to a progressive diet without protein supplementation. Material and Methods Study Design A descriptive cohort study was designed, including 181 patients who underwent metabolic and bariatric surgery between 2013 and 2023. A historical cohort (2013–2020) that did not receive oral supplementation was compared to a prospective cohort (2020–2023) with oral supplementation. After obtaining signed informed consent from each patient, variables were collected at baseline, and at one and six months after surgery. The study was approved by the Ethics Committee of the Eastern Valladolid Area (code PI xx-xxxx) and was conducted in accordance with the principles of the Declaration of Helsinki. Study Subjects Selected patients met the following inclusion criteria: adults diagnosed with obesity (BMI ≥ 30 kg/m²) in the month following metabolic and bariatric surgery (sleeve gastrectomy, gastric bypass, and biliopancreatic diversion), aged between 18 and 65 years. Exclusion criteria included other types of metabolic and bariatric surgery (single-anastomosis duodeno-ileal bypass with sleeve gastrectomy, SADIS), endoscopic weight loss techniques (intragastric balloon, APOLLO, endo-sleeve, etc.) and patients who did not sign informed consent. Nutritional Intervention The study cohort was divided into patients who received a low-protein diet (LPD) or a high-protein diet (HPD). The LPD consisted of a liquid diet followed by a semi-liquid diet during the first four weeks after surgery with natural foods (Table 1 ). Table 1 Diet composition in each group for the first four weeks Low-protein diet High-protein diet First 2 weeks Last 2 weeks First 2 weeks Last 2 weeks Energy (Kcal) 217 1155.5 817 1155.5 Protein (g) 11.70 65.95 65.70 65.95 Carbohydrates (g) 37.40 164.45 97.40 164.45 Fat (g) 1.73 22.12 14.33 22.12 Fiber (g) 2.32 17.39 17.32 17.39 Kcal: kilocalorie; g: grams Patients on HPD received a liquid and semi-liquid diet during the first four weeks after surgery, supplemented with 600 ml per day of a normocaloric, high-protein oral nutritional supplement (Bi1 Bificare®, Adventia Pharma, Las Palmas de Gran Canaria, Spain) (Table 2 ) Table 2 Composition of oral nutritional supplementation Oral nutritional supplement 100 ml 600 ml Energy (kcal) 100 600 Protein (g/%) 9/36% 54/36% Carbohydrates (g/%) 10/40% 60/40% Sugars (g) 1.1 6,6 Fat (g/%) 2.1/19% 12.6/19% MUFA (%) 10 10 PUFA (%) 4,7 4,7 EPA&DHA (mg) 170 1220 Fibra (g)/soluble-insoluble 2.5/70%-30% 15/70%-30% BPL-1 1.6710 UFC 1010 UFC Kcal: kilocalorie; g: gram; mg: milligram; MUFA: monounsaturated fatty acids; PUFAs: polyunsaturated fatty acids; EPA: icosapentaenoic acid; DHA: docosahexaenoic acid; GLP-1: Bifidobacterium animalis subsp ; CFU: colony-forming units Variables Epidemiological Variables Gender and age of the patient were recorded. Gender was divided into male and female. Age was recorded as the age at which the patient was referred for MBS. Anthropometric Variables Measured anthropometric variables included weight (kg) and height (cm). Body mass index (BMI) was calculated as weight/height × height (kg/m²); percentage of weight loss (%WL) as (preoperative weight (kg) compared to actual weight (kg)) / (usual weight (kg) × 100). Measurements were always performed by the same person. Body Composition Variable : Body composition was determined by bioelectrical impedance analysis (BIA). Bioimpedance (BIA NutriLab; EFG Akern, Akern, Pisa, Italy) was performed between 8:00 and 9:15 a.m. after overnight fasting and after 15 minutes in the supine position. BIA determines body composition assuming the human body is composed of fat mass (FM) and lean mass (LM); LM is further composed of muscle mass, bone mass, and total body water (TBW). TBW was calculated using the formula described by Kushner et al. ( 11 ): TBW = 8.315 + (0.382 × height (cm)² / Resistance) + 0.105 × Weight (kg). Appendicular skeletal muscle mass (ASMM) was calculated using the Sergi Formula ( 12 ): ASMM = -3.964 + (0.227 × RI) + (0.095 × Weight (kg)) + (1.384 × Sex) + (0.064 × Xc), where RI: resistivity index = (Height (cm))/R²; Sex: Male = 1; Female = 0. Lean mass and appendicular skeletal muscle mass were standardized by height squared (height²). These were defined as lean mass index (LMI) and appendicular skeletal muscle mass index (ASMMI) in kg/m². These variables were applied as percentile curves from the Bodygram® program developed by Akern for ages 18 to 98 years. Differences in body composition variables between follow-up times were also calculated. Statistical Analysis The database was registered with authorization from the National Data Protection Agency. Collected data were stored in a database using SPSS 23.0 statistical software (SPSS Inc., Chicago, IL, USA). Qualitative variables were expressed as percentages and analyzed using the Chi-square test, with Fisher and Yates adjustments when necessary. Continuous variables were shown as mean and standard deviation, while parametric variables were analyzed using the unpaired Student’s t-test. For non-parametric variables, tests such as Friedman, Wilcoxon, and Mann-Whitney U were used. ANOVA U with Bonferroni post-hoc test was applied to compare variables in more than two groups. Analysis of variables at different study times was performed using multivariate analysis of variance (MANOVA). A p-value less than 0.05 was considered significant. Results Sample Description Ninety-three patients were assigned to the intervention group (HPD), and eighty-nine were assigned to the historical cohort (LPD). There were eleven losses to follow-up in the historical cohort and two in the intervention group (Fig. 1 ). The mean age of the sample was 45.2 (10.1) years, and 68.5% were women (n = 124). The mean preoperative weight was 129.6 (25.2) kg, and the mean BMI was 47.2 (6.3) kg/m². The most common surgical technique was sleeve gastrectomy (SG) 77.3% (n = 140), followed by BPD 14.9% (n = 27) and GB 7.8% (n = 14). There were differences in the distribution of techniques and initial mean lean mass in each diet type (Table 3 ). Differences by sex are shown in Table 3 . Differences between surgical techniques are shown in Table 4 . Table 3 Anthropometric and body composition variables at baseline stratified by type of protein supplementation Body composition variables Low-protein diet n = 93 High-protein diet n = 88 p Gender (Males/Females) % 57.9/48.4 42.1/51.6 0.77 Type of surgery (Restrictive techniques/malabsorptive techniques) 66.6/33.4 88.7/11.3 0.00 BMI (Kg/m2) 46.94 (6.01) 47.41 (.,67) 0.62 Total Body Water TBW (Kg) 46.92 (7.88) 47.16 (8.88) 0.93 Lean mass index LMI (kg/m2) 23.98 (4.39) 16.89 (4.38) 0.01 Fat mass index FMI (Kg/m2) 22.09 (5.01) 21.65 (5.88) 0.87 Appendicular skeletal muscle mass index ASMMI (kg/m2) 9.64 (1.32) 10.32 (1.21) 0.35 Resistance (ohm) 436.11 (63.27) 471.99 (68.19) 0.09 Reactance (ohm) 48.15 (12.51) 45.08 (6.27) 0.44 Phase Angle PA ( ◦) 6.55 (1.52) 6.35 (1.04) 0.74 BMI: body mass index; ACT: total body water; LMI: lean mass index; FMI fat mass index; ASMMI: Appendicular skeletal muscle mass index; R: resistance; Rc: reactance; PA: Phase Angle; Kg: kg; cm: centimeters; m: meters; ◦: Angle Table 4 Anthropometric and body composition variables at the beginning of the study stratified by type of protein supplementation and surgical technique Body composition variables Low-protein diet n = 93 p High-protein diet n = 88 p Restrictive techniques n = 62 Mixed/malabsorptive techniques n = 31 Restrictive techniques n = 78 Mixed/malabsorptive techniques n = 10 Gender (Males/Females)% 29.1/70.9 48.4/51.6 0.11 30.7/69.3 0/100 0.04 BMI (Kg/m 2 ) 46.03 (5.86) 48.76 (6.01) 0.18 47.65 (6.75) 45.59 (6.05) 0.34 Total body wáter TBW (Kg) 45.66 (6.91) 51.22 (9.75) 0.11 49.09 (9.39) 42.34 (5.80) 0.21 Lean mass index LMI (kg/m 2 ) 23.43 (3.78) 24.89 (5.33) 0.42 15.81 (4.54) 20.12 (1.89) 0.12 Fat mass index FMI (kg/m 2 ) 21.94 (5.45) 22.36 (4.43) 0.84 22.81 (5.51) 19.34 (8.11) 0.66 Appendicular skeletal muscle mass index ASMMI (kg/m 2 ) 9.39 (1.26) 10.48 (1.18) 0.03 9.13 (1.65) 10.72 (1.12) 0.34 Resistance (ohm) 448.29 (63.76) 349.70 (41.83) 0.02 459.06 (67.56) 504.30 (67.17) 0.30 Reactance (ohm) 48.49 (9.06) 46.96 (21.31) 0.74 43.77 (6.97) 49.01 (7.32) 0.58 Phase Angle PA ( ◦) 6.34 (1.08) 7.42 (2.56) 0.25 6.60 (1.12) 5.60 (2.87) 0.51 BMI: body mass index; TBW: total body water; LMI: lean mass index; FMI: fat mass index; ASMMI: Appendicular skeletal muscle mass index; R: resistance; Rc: reactance; PA: Phase Angle; Kg: kg; cm: centimeters; m: meters; ◦: Angle Changes in Anthropometric Variables Table 5 describes the anthropometric variables before surgery, as well as changes at one and six months according to diet type. Table 5 Evolution of anthropometric and body composition variables stratified by type of protein supplementation Body composition variables Low-protein diet n = 93 p High-protein diet n = 88 p Pre-surgery n = 93 1 mes n = 88 6 months n = 82 Presurgery n = 88 1 mes n = 87 6 months n = 85 Weight (Kg) 130.55 (24.03) 112.65 (20.51) 100.44 (19.05) 0.00 129.40 (26.39) 115.29 (24.63) 103.84 (22.72) 0.00 BMI Kg/m 2 ) 47.26 (5.89) 40.82 (5.35) 36.40 (5.21) 0.00 47.35 (6.69) 42.31 (6.67) 38.25 (6.48) 0.00 Total body water TBW (Kg) 45.81 (7.75) 43.89 (7.41) 44.36 (6.12) 0.01 47.21 (12.13) 47.08 (9.83) 45.73 (9.06) 0.59 Lean mass index LMI (kg/m 2 ) 24.03 (4.52) 22.67 (4.12) 21.08 (3.56) 0.01 16.23 (4.29) 16.54 (3.79) 16.27 (4.02) 0.67 Fat mass index FMI (kg/m 2 ) 22.76 (2.51) 19.19 (2.75) 16.36 (3.76) 0.01 24.19 (5.84) 19.68 (3.41) 15.18 (4.21) 0.03 Appendicular skeletal muscle mass index ASMMI (kg/m 2 ) 9.63 (1.54) 8.95 (1.22) 8.81 (1.09) 0.01 10.28 (1.48) 9.78 (1.24) 8.61 (1.06) 0.26 Resistance (ohm) 441.83 (65.88) 447.17 (74.07) 433.73 (70.63) 0.86 487.77 (89.33) 452.33 (77.91) 432.41 (73.23) 0.22 Reactance (ohm) 50.92 (14.50) 47.75 (13.81) 45.83 (11.46) 0.33 44.83 (7.65) 51.30 (10.11) 46.45 (10.62) 0.38 Phase PA ( ◦) 6.75 (2.46) 6.28 (1.74) 5.83 (1.04) 0.19 6.20 (1.22) 7.04 (1.64) 6.41 (1.26) 0.07 BMI: body mass index; TBW: total body water; LMI lean mass index; FMI: fat mass index; ASMMI: Appendicular skeletal muscle mass index; R: resistance; Rc: reactance; PA: Phase Angle; Kg: kg; cm: centimeters; m: meters; ◦: Angle There was a mean weight loss in the first month of 12.11 (5.84) %; 13.18 (5.21) kg in men; 11.49 (6.03) kg in women (p = 0.03). The mean weight loss at six months was 21.16 (8.09) %; 23.76 (7.68) kg in men and 19.84 (7.99) kg in women (p = 0.01). There was a significant loss of weight and BMI in both groups (Table 5 ). The percentage of weight loss one month after metabolic and bariatric surgery was 13.44% (6.71%) in the LPD group and 10.78% (4.45%) in the HPD group, with statistically significant differences (p = 0.01). The percentage of weight loss at six months was 22.89% (8.78%) in the LPD group and 19.49% (7.01%) in the HPD group, also with significant differences (p = 0.01). Changes in Bioimpedance Parameters After the first month post-surgery, there was an increase in resistance in both groups, with no significant differences (+ 5.33 (29.59) LPD vs. +4.83 (52.10) HPD, p = 0.29), as well as a loss of reactance (-3.17 (17.06)) and phase angle (-0.48 (2.13)) in LPD and a gain in HPD (+ 6.47 (6.27); +0.83 (1.11)), although without reaching statistical significance. Figure 2 shows the differences in body composition between groups. Maintenance of lean mass index is observed in HPD and a loss in LPD. At six months post-surgery, there was a more marked loss of resistance and reactance in LPD, as well as a gain in phase angle in HPD and a loss in LPD, as shown in Fig. 3 . There was a loss of total body water, fat mass index, and appendicular skeletal muscle mass index at six months, similar in both groups. The loss of lean mass was greater in the LPD group (Fig. 4 ). Discussion Patients who received protein supplementation with a normocaloric, high-protein oral nutritional supplement to complete their caloric-protein requirements during the first two weeks after metabolic and bariatric surgery maintained phase angle and lean mass index to a greater extent than those patients without supplementation. Weight loss was greater in the group without protein supplementation; however, fat mass loss was similar between both groups in the first six months after surgery. Baseline characteristics between both groups were similar, except for a higher representation of malabsorptive techniques in the LPD group and a higher lean mass index in this group. When stratified by surgical technique, there were no baseline differences in the HPD group, while in the LPD group, patients who underwent malabsorptive techniques started with a higher appendicular skeletal muscle mass index and lower reactance than those with restrictive techniques. Female sex was the most prevalent in all groups. Weight loss was greater in the LPD group, although both groups showed significant weight and BMI loss over time. Some studies indicate that weight loss after surgery in patients who received protein supplementation does not differ significantly from those without postoperative protein supplementation ( 13 ). Other studies show a positive correlation between weight loss and protein intake ( 14 , 15 ). Meanwhile, other authors report more pronounced weight loss in patients without protein supplementation ( 16 , 17 ), as in our study, probably related to loss of fat-free mass. Progressive diets restricted in protein, intolerance to protein secondary to reduced gastric chamber, and malabsorption from techniques that modify the duodenum result in nearly half of patients not consuming the recommended protein intake after surgery ( 18 ). The effect of protein supplementation on the maintenance of fat-free mass is controversial. Some studies support the hypothesis that protein supplementation improves or maintains fat-free mass after surgery ( 19 , 20 , 21 , 22 ), while others do not support this hypothesis ( 23 ). Ranjbar et al. ( 22 ), in a recent meta-analysis of 10 randomized clinical trials with patients undergoing mixed and malabsorptive techniques, concluded that the group with protein supplementation maintained muscle mass (1.33 kg, 95% CI: 0.1 to 2.57, p = 0.035), fat-free mass (1.74 kg, 95% CI: 0.46 to 3.01, p = 0.01), and lost fat mass (-3.91 kg, 95% CI: -4.10 to -0.59, p = 0.01) to a greater extent than the control group, results similar to those obtained in our study. The type of protein supplementation has also been evaluated to determine the most suitable protein type. It is postulated that supplementation with short peptides may be better tolerated due to their smaller size and greater ease of absorption ( 24 ). Comas et al. ( 25 ), in a study with GB patients, used short peptides, complex peptides, or a supplement enriched with hydroxymethylbutyrate (HMB). Fat-free mass one month after surgery was better maintained in patients with short peptides (40.60 ± 17.27 in complex protein supplementation, 34.57 ± 13.15 kg in HMB, and 19.14 ± 9.38 kg in short peptide supplementation, p < 0.001). The supplement in our study contained whey protein, calcium caseinate, was enriched in L-leucine, and contained the probiotic Bifidobacterium animalis. The use of probiotics after MBS has been previously studied, relating their use to greater weight loss, lower caloric intake, and improvement in lipid and hepatic profiles ( 26 , 27 ). The surgical technique may be one of the factors influencing body composition and weight loss after surgery. In our study, SG was the most common technique, although patients with malabsorptive techniques started with a higher ASMMI, without other baseline differences. Maintenance of fat-free mass with protein supplementation has been described for both restrictive ( 28 , 29 ) and malabsorptive ( 30 , 31 ) techniques. Finally, it is worth mentioning the maintenance of phase angle in patients who received protein supplementation. The decrease in phase angle after MBS seems to have a paradoxical value, as excessive weight loss reduces comorbidities associated with obesity and improves health; however, a low phase angle is associated with malnutrition and/or nutritional risk. Previous studies have associated the decrease in phase angle after surgery with loss of visceral protein mass, muscle mass, and worsening of protein nutritional status ( 32 ). In our sample, significant maintenance of phase angle occurred from six months onward, in line with findings from other studies ( 33 ). This study has several limitations that should be considered when interpreting its results. First, it is a retrospective cohort study, which implies possible selection bias and a lower capacity to establish causal relationships. In addition, the comparison between groups was made with a historical cohort, which may introduce uncontrolled variability in the intervention, follow-up, or outcome assessment. Randomization of participants was not performed, limiting homogeneity between groups and possibly influencing the baseline differences observed, especially in the type of surgical technique and initial lean mass index. Adherence to protein supplementation was not systematically recorded, nor was gastrointestinal tolerance documented, both key aspects in this type of intervention. Another relevant limitation is the absence of quantitative recording of physical activity during follow-up, a variable that may influence lean mass evolution. Finally, some body composition parameters were estimated from validated equations, which implies indirect inference and possible margin of error, especially in patients with morbid obesity. Among the main strengths of this work are the relatively large sample size and the inclusion of patients undergoing different surgical techniques, allowing for a more representative evaluation of routine clinical practice. The six-month follow-up provides relevant information on medium-term changes in body composition after metabolic and bariatric surgery. Likewise, the use of multifrequency bioimpedance allows for a detailed assessment of body compartments such as lean mass index, phase angle, or appendicular skeletal muscle mass index. The nutritional intervention was applied by qualified personnel with specific training, ensuring greater uniformity in dietary education and initial follow-up. Finally, the study provides evidence on the impact of early protein supplementation on the maintenance of lean mass and functional parameters, which may help optimize nutritional management in the immediate postoperative period of patients with obesity undergoing bariatric surgery. Conclusions The administration of a normocaloric, high-protein oral nutritional supplement during the first weeks after metabolic and bariatric surgery was associated with greater preservation of lean mass index and phase angle, without compromising medium-term fat mass loss. Although the group without supplementation showed greater total weight loss, this difference could be attributed to a greater reduction in fat-free mass, which may have negative implications for patient functionality and nutritional status. These findings highlight the importance of an adequate nutritional strategy in the immediate postoperative period, especially aimed at meeting protein requirements. Early supplementation could represent an effective and safe intervention to minimize muscle catabolism and improve the quality of weight loss. Future prospective and randomized studies will be necessary to confirm these results and establish individualized recommendations according to surgical technique and baseline patient characteristics. Declarations Conflicts of interest: there are no conflicts of interest to declare. Author Contribution Conceptualization, J.J.L.-G. and BRB; Data curation, ., B.R.B. and J.G.-G.; Formal analysis, BRB.; Investigation, J.J.L.-G., B.R.-B., D.P.-M., R.J.S, MSV,PPL.-G., E.L.A., D.P.-S. and P.P.-F.; Methodology, J.J.L.-G. and D.A.D.L.-R. and BRB; Resources, BRB. and D.A.D.L.-R.; Software, J.J.L.-G.; Validation, J.J.L.-G. and D.A.D.L.-R.; Writing—original draft, BRB.; Writing—review and editing, J.J.L.-G. and D.A.D.L.-R. All authors have read and agreed to the published version of the manuscript. References Cebrián Cuenca AM, Escalada J. Prevalencia de obesidad y diabetes en España. Evolución en los últimos 10 años [Prevalence of obesity and diabetes in Spain. Evolution in the last 10 years]. 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J Bone Min Res. 2016;31(3):672–82. 10.1002/jbmr.2707 . Comas Martinez M, Fidilio Meli E, Palmas Candia F, Cordero E, Hernandez I, Vilallonga R, Burgos R, Vila A, Simo R, Ciudin A. La suplementación proteica con péptidos cortos previene la pérdida temprana de masa muscular después del bypass gástrico en Y de Roux. Nutrientes. 2022;14:5095. [DOI] [Artículo gratuito de PMC] [PubMed] [Google Académico]. Guillet C, Masgrau A, Mishellany-Dutour A, Blot A, Caille A, Lyon N, Pereira B, Slim K, Robert M, Disse E, Feugier N, Le Ruyet P, Louvet C, Miolanne M, Farigon N, Laville M, Boirie Y. Bariatric surgery affects obesity-related protein requirements. Clin Nutr ESPEN. 2020;40:392–400. Romeijn MM, Holthuijsen DDB, Kolen AM, Janssen L, Schep G, van Dielen FMH, Leclercq WK G. The effect of additional protein on lean body mass preservation in post-bariatric surgery patients: a systematic review. Nutr J. 2021;20(1):27. https://doi.org/10.1186/s12937-021-00688-3 . Gunes Y, Karip B, Ergin A, Esen Bulut N, Fersahoglu MM, Memisoglu K. El impacto del aporte proteico en la pérdida de peso, la sarcopenia y la calidad de vida después de una gastrectomía en manga. Bariatr Surg Pract Patient Care. 2019;14(3):131–6. 10.1089/bari.2018.0057 . Schiavo L, Scalera G, Pilone V, De Sena G, Quagliariello V, Iannelli A, et al. Un estudio comparativo que examina el impacto de una dieta posoperatoria rica en proteínas frente a una dieta con proteínas normales en la composición corporal y la tasa metabólica en reposo en pacientes obesos después de una gastrectomía en manga. Obes Surg. 2017;27(4):881–8. 10.1007/s11695-016-2382-y . Ranjbar M, Fallah M, Djafarian K, Mohammadi H, Farsani M, G., Shab-Bidar S. Los efectos de la suplementación con proteínas en la composición corporal después de la cirugía bariátrica: una revisión sistemática y metaanálisis de ensayos controlados aleatorios. Obesidad (Silver Spring Maryland). 2025;33(6):1027–36. https://doi.org/10.1002/oby.24283 . Maimoun L, Lefebvre P, Jaussent A, Fouillade C, Mariano-Goulart D, Nocca D. Cambios en la composición corporal en el primer mes después de la gastrectomía en manga según el sexo y el sitio anatómico. Relat Dis. 2017;13:780–7. 10.1016/j.soard.2017.01.017 . Zhan D, Long Z, Yang H, Wang H, He C, Yin J, Yu J, Fu L, Liu Y. Protein Supplements with Short Peptides Are Better than Complex Protein-Based Supplements on Improving Early Fat-Free Mass Loss Following Bariatric Surgery: A Retrospective Cohort Study. Obes Surg. 2024;34(5):1608–17. es/10.1007/s11695-024-07157-w . https://doiorg.publicaciones.saludcastillayleon. . Comas Martínez M, Fidilio Meli E, Palmas Candia F, Cordero E, Hernández I, Vilallonga R, Burgos R, Vila A, Simó R, Ciudin A. Protein Supplementation with Short Peptides Prevents Early Muscle Mass Loss after Roux-en-Y-Gastric Bypass. Nutrients. 2022;14(23):5095. https://doi.org/10.3390/nu14235095 . Wang Y, Zheng Y, Kuang L, Yang K, Xie J, Liu X, Shen S, Li X, Wu S, Yang Y, Shi J, Wu J, Wang Y. (2023). Effects of probiotics in patients with morbid obesity undergoing bariatric surgery: a systematic review and meta-analysis. International journal of obesity (2005), 47(11), 1029–1042. Ghafouri-Taleghani F, Tafreshi AS, Doost AH, Tabesh M, Abolhasani M, Amini A, Saidpour A. Effects of Probiotic Supplementation Added to a Weight Loss Program on Anthropometric Measures, Body Composition, Eating Behavior, and Related Hormone Levels in Patients with Food Addiction and Weight Regain After Bariatric Surgery: A Randomized Clinical Trial. Obes Surg. 2024;34(9):3181–94. Afsar N, Ozdogan Y. Protein supplementation preserves muscle mass in persons against sleeve gastrectomy. Front Nutr. 2024;11:1476258. https://doi.org/10.3389/fnut.2024.1476258 . Sherf Dagan S, Tovim TB, Keidar A, Raziel A, Shibolet O, Zelber-Sagi S. Inadequate protein intake after laparoscopic sleeve gastrectomy surgery is associated with a greater fat free mass loss. Surg Obes Relat diseases: official J Am Soc Bariatr Surg. 2017;13(1):101–9. https://doi.org/10.1016/j.soard.2016.05.026 . Nuijten MAH, Eijsvogels TMH, Sanders B, Vriese LM, Monpellier VM, Hazebroek EJ, Janssen IMC, Hopman MTE. Changes in Fat-Free Mass, Protein Intake and Habitual Physical Activity Following Roux-en-Y Gastric Bypass Surgery: A Prospective Study. Obes Surg. 2023;33(7):2148–57. https://doi.org/10.1007/s11695-023-06650-y . Haghighat N, Kazemi A, Asbaghi O, Jafarian F, Moeinvaziri N, Hosseini B, Amini M. Long-term effect of bariatric surgery on body composition in patients with morbid obesity: A systematic review and meta-analysis. Clin Nutr. 2021;40(4):1755–66. Bortoli AM, Braga GB, Brito BB, Moraes RAG, Miguel GPS, Pedrosa RG, Haraguchi FK. Decrease phase angle one year after Roux-en-Y bypass and sleeve gastrectomy is related to risks to protein nutritional status. Clin Nutr ESPEN. 2022;52:138–43. https://doi.org/10.1016/j.clnesp.2022.10.018 . Navarro-Marroco J, Hernández-Sánchez P, Victoria-Montesinos D, Barcina-Pérez P, Lucas-Abellán C, García-Muñoz AM. Comparative Effects of Sleeve Gastrectomy vs. Roux-en-Y Gastric Bypass on Phase Angle and Bioelectrical Impedance Analysis Measures: A Systematic Review and Meta-Analysis. J Clin Med. 2024;13(22):6784. https://doi.org/10.3390/jcm13226784 . Additional Declarations No competing interests reported. Supplementary Files VISUALABSTRACTOBSU.pptx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7951468","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":546521743,"identity":"b37dea0d-fb81-4477-b3ab-bae5e485f0b6","order_by":0,"name":"Beatriz 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Hortega","correspondingAuthor":false,"prefix":"","firstName":"PIlar","middleName":"Pinto","lastName":"Fuentes","suffix":""},{"id":546521752,"identity":"acd358e1-d787-4fa4-a8da-76629f59575d","order_by":8,"name":"David Pacheco Sánchez","email":"","orcid":"","institution":"Hospital Universitario Río Hortega","correspondingAuthor":false,"prefix":"","firstName":"David","middleName":"Pacheco","lastName":"Sánchez","suffix":""},{"id":546521753,"identity":"3ca60b76-eaa6-4522-ac3c-c06b7110f4d6","order_by":9,"name":"Daniel Antonio De Luis Román","email":"","orcid":"","institution":"Hospital Clínico Universitario de Valladolid","correspondingAuthor":false,"prefix":"","firstName":"Daniel","middleName":"Antonio De Luis","lastName":"Román","suffix":""}],"badges":[],"createdAt":"2025-10-27 11:14:30","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7951468/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7951468/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":98752249,"identity":"07ffbf75-78dd-4e70-9ae2-e7d4426f79ee","added_by":"auto","created_at":"2025-12-22 09:15:33","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":58382,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of protein supplementation\u003c/p\u003e","description":"","filename":"Picture1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7951468/v1/2286fc193797792512e647d9.jpg"},{"id":98780447,"identity":"59f10960-794d-448d-81a1-8d009d08d6d8","added_by":"auto","created_at":"2025-12-22 12:31:22","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":44501,"visible":true,"origin":"","legend":"\u003cp\u003eBetween-group comparison (high-protein diet and low-protein diet) of changes in body composition compartments determined by bioimpedance measurement (total body water, fat-free mass index, fat index, and appendicular skeletal muscle index) before and 1 month after bariatric surgery.\u003c/p\u003e","description":"","filename":"Picture2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7951468/v1/0992ae2cab6b6a0d1bab5b2f.jpg"},{"id":98752245,"identity":"8c8e8ec5-0af8-4ef5-8efe-2fff3a6561f9","added_by":"auto","created_at":"2025-12-22 09:15:33","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":28835,"visible":true,"origin":"","legend":"\u003cp\u003eComparison between groups (high protein diet and low protein diet) of changes in electrical bioimpedance variables (resistance, reactance and phase angle) before and six months after bariatric surgery\u003c/p\u003e","description":"","filename":"Picture3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7951468/v1/458250766dcff375e3c94f7c.jpg"},{"id":98778113,"identity":"c36c0c71-d9ea-46a9-8eb6-fc9c20b0f920","added_by":"auto","created_at":"2025-12-22 12:28:55","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":43737,"visible":true,"origin":"","legend":"\u003cp\u003eBetween-group comparison (high-protein diet and low-protein diet) of changes in body composition compartments determined by bioimpedance measurement (total body water, fat-free mass index, fat index, and appendicular skeletal muscle index) before and 6 months after bariatric surgery.\u003c/p\u003e","description":"","filename":"Picture4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7951468/v1/7f1c8a14652e6340b3b02743.jpg"},{"id":100360194,"identity":"e963dde0-2f86-4c45-9933-b06135dc4b70","added_by":"auto","created_at":"2026-01-16 07:37:58","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1541158,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7951468/v1/63faff96-4916-4785-8748-73c3f172bf23.pdf"},{"id":98752246,"identity":"90369510-972b-45cb-bf60-b80feec37358","added_by":"auto","created_at":"2025-12-22 09:15:33","extension":"pptx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":1104262,"visible":true,"origin":"","legend":"","description":"","filename":"VISUALABSTRACTOBSU.pptx","url":"https://assets-eu.researchsquare.com/files/rs-7951468/v1/c2de226810ca4e66eaaa4efb.pptx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Effect on Body Composition of Protein Supplementation During the First Six Months After Bariatric Surgery","fulltext":[{"header":"Key Points","content":"\u003cp\u003e\u003cimg src=\"https://myfiles.space/user_files/69519_bce2c0439cd956a6/69519_custom_files/img1765998698.png\"\u003e\u003c/p\u003e"},{"header":"Introduction","content":"\u003cp\u003eThe prevalence of overweight and obesity has increased in recent decades worldwide and across all age groups, including children and adolescents (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). Metabolic and bariatric surgery (MBS) is a treatment option for individuals with obesity who do not achieve sufficient weight loss with lifestyle measures and medications. It is also the only treatment option that has demonstrated long-term weight loss maintenance (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). MBS techniques can be divided into restrictive or mixed/malabsorptive. Although the most widely used technique globally is gastric bypass (GB) (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e), there is currently a growing trend toward restrictive procedures(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eNutritional deficiencies are the most frequent complication after MBS, secondary to modifications of the gastrointestinal tract, progressive diets, and reduced gastric reservoir, leading to dietary restriction and malabsorption (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). The progressive diet is based on a gradual modification of food volumes and textures until tolerance of a balanced diet is achieved. In the first weeks after surgery, the liquid diet, based on water, infusions, or clear broths, rarely meets the minimum protein recommendations of 60 g/day (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). This protein deficit in the early weeks after surgery can lead to loss of fat-free mass and affect patient functionality (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eProtein deficiency is the most common macronutrient deficiency after MBS (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). It is more prevalent in patients undergoing mixed/malabsorptive techniques such as biliopancreatic diversion (BPD) or GB. It is estimated that between 7\u0026ndash;21% of patients with BPD present with protein malnutrition due to maldigestion and absorption secondary to altered biliary and pancreatic function (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). In GB patients, protein malnutrition is found in 13% after two years, especially if the alimentary limb is longer than 150 cm, or 5% if shorter (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). In restrictive techniques, protein malnutrition can occur if protein sources are avoided for prolonged periods, with frequent vomiting or diarrhea, food intolerances, or alcoholism(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eProtein supplementation after MBS emerges as an option to prevent protein malnutrition and its consequences. The main objective of this study is to evaluate the effect of early oral protein supplementation after surgery on body composition up to six months postoperatively, compared to a progressive diet without protein supplementation.\u003c/p\u003e"},{"header":"Material and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Design\u003c/h2\u003e \u003cp\u003eA descriptive cohort study was designed, including 181 patients who underwent metabolic and bariatric surgery between 2013 and 2023. A historical cohort (2013\u0026ndash;2020) that did not receive oral supplementation was compared to a prospective cohort (2020\u0026ndash;2023) with oral supplementation. After obtaining signed informed consent from each patient, variables were collected at baseline, and at one and six months after surgery. The study was approved by the Ethics Committee of the Eastern Valladolid Area (code PI xx-xxxx) and was conducted in accordance with the principles of the Declaration of Helsinki.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eStudy Subjects\u003c/h3\u003e\n\u003cp\u003eSelected patients met the following inclusion criteria: adults diagnosed with obesity (BMI\u0026thinsp;\u0026ge;\u0026thinsp;30 kg/m\u0026sup2;) in the month following metabolic and bariatric surgery (sleeve gastrectomy, gastric bypass, and biliopancreatic diversion), aged between 18 and 65 years. Exclusion criteria included other types of metabolic and bariatric surgery (single-anastomosis duodeno-ileal bypass with sleeve gastrectomy, SADIS), endoscopic weight loss techniques (intragastric balloon, APOLLO, endo-sleeve, etc.) and patients who did not sign informed consent.\u003c/p\u003e\n\u003ch3\u003eNutritional Intervention\u003c/h3\u003e\n\u003cp\u003eThe study cohort was divided into patients who received a low-protein diet (LPD) or a high-protein diet (HPD). The LPD consisted of a liquid diet followed by a semi-liquid diet during the first four weeks after surgery with natural foods (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDiet composition in each group for the first four weeks\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eLow-protein diet\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eHigh-protein diet\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFirst 2 weeks\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLast 2 weeks\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eFirst 2 weeks\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLast 2 weeks\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eEnergy (Kcal)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e217\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1155.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e817\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1155.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eProtein (g)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e65.95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e65.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e65.95\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCarbohydrates (g)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e37.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e164.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e97.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e164.45\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFat (g)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e22.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e14.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e22.12\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFiber (g)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e17.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e17.39\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eKcal: kilocalorie; g: grams\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003ePatients on HPD received a liquid and semi-liquid diet during the first four weeks after surgery, supplemented with 600 ml per day of a normocaloric, high-protein oral nutritional supplement (Bi1 Bificare\u0026reg;, Adventia Pharma, Las Palmas de Gran Canaria, Spain) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComposition of oral nutritional supplementation\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOral nutritional supplement\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100 ml\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e600 ml\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eEnergy (kcal)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e600\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eProtein (g/%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9/36%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e54/36%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCarbohydrates (g/%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10/40%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e60/40%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSugars (g)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6,6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFat (g/%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.1/19%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12.6/19%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMUFA (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePUFA (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4,7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4,7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eEPA\u0026amp;DHA (mg)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e170\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1220\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFibra (g)/soluble-insoluble\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.5/70%-30%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15/70%-30%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBPL-1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.6710 UFC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1010 UFC\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003eKcal: kilocalorie; g: gram; mg: milligram; MUFA: monounsaturated fatty acids; PUFAs: polyunsaturated fatty acids; EPA: icosapentaenoic acid; DHA: docosahexaenoic acid; GLP-1: \u003cem\u003eBifidobacterium animalis subsp\u003c/em\u003e; CFU: colony-forming units\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003eVariables\u003c/h3\u003e\n\u003cp\u003e \u003cstrong\u003eEpidemiological Variables\u003c/strong\u003e \u003cp\u003eGender and age of the patient were recorded. Gender was divided into male and female. Age was recorded as the age at which the patient was referred for MBS.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eAnthropometric Variables\u003c/strong\u003e \u003cp\u003eMeasured anthropometric variables included weight (kg) and height (cm). Body mass index (BMI) was calculated as weight/height \u0026times; height (kg/m\u0026sup2;); percentage of weight loss (%WL) as (preoperative weight (kg) compared to actual weight (kg)) / (usual weight (kg) \u0026times; 100). Measurements were always performed by the same person.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eBody Composition Variable\u003c/b\u003e: Body composition was determined by bioelectrical impedance analysis (BIA). Bioimpedance (BIA NutriLab; EFG Akern, Akern, Pisa, Italy) was performed between 8:00 and 9:15 a.m. after overnight fasting and after 15 minutes in the supine position. BIA determines body composition assuming the human body is composed of fat mass (FM) and lean mass (LM); LM is further composed of muscle mass, bone mass, and total body water (TBW). TBW was calculated using the formula described by Kushner et al. (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e): TBW\u0026thinsp;=\u0026thinsp;8.315 + (0.382 \u0026times; height (cm)\u0026sup2; / Resistance)\u0026thinsp;+\u0026thinsp;0.105 \u0026times; Weight (kg). Appendicular skeletal muscle mass (ASMM) was calculated using the Sergi Formula (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e): ASMM = -3.964 + (0.227 \u0026times; RI) + (0.095 \u0026times; Weight (kg)) + (1.384 \u0026times; Sex) + (0.064 \u0026times; Xc), where RI: resistivity index = (Height (cm))/R\u0026sup2;; Sex: Male\u0026thinsp;=\u0026thinsp;1; Female\u0026thinsp;=\u0026thinsp;0. Lean mass and appendicular skeletal muscle mass were standardized by height squared (height\u0026sup2;). These were defined as lean mass index (LMI) and appendicular skeletal muscle mass index (ASMMI) in kg/m\u0026sup2;. These variables were applied as percentile curves from the Bodygram\u0026reg; program developed by Akern for ages 18 to 98 years. Differences in body composition variables between follow-up times were also calculated.\u003c/p\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eThe database was registered with authorization from the National Data Protection Agency. Collected data were stored in a database using SPSS 23.0 statistical software (SPSS Inc., Chicago, IL, USA).\u003c/p\u003e \u003cp\u003eQualitative variables were expressed as percentages and analyzed using the Chi-square test, with Fisher and Yates adjustments when necessary. Continuous variables were shown as mean and standard deviation, while parametric variables were analyzed using the unpaired Student\u0026rsquo;s t-test. For non-parametric variables, tests such as Friedman, Wilcoxon, and Mann-Whitney U were used. ANOVA U with Bonferroni post-hoc test was applied to compare variables in more than two groups. Analysis of variables at different study times was performed using multivariate analysis of variance (MANOVA). A p-value less than 0.05 was considered significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eSample Description\u003c/h2\u003e \u003cp\u003eNinety-three patients were assigned to the intervention group (HPD), and eighty-nine were assigned to the historical cohort (LPD). There were eleven losses to follow-up in the historical cohort and two in the intervention group (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe mean age of the sample was 45.2 (10.1) years, and 68.5% were women (n\u0026thinsp;=\u0026thinsp;124). The mean preoperative weight was 129.6 (25.2) kg, and the mean BMI was 47.2 (6.3) kg/m\u0026sup2;. The most common surgical technique was sleeve gastrectomy (SG) 77.3% (n\u0026thinsp;=\u0026thinsp;140), followed by BPD 14.9% (n\u0026thinsp;=\u0026thinsp;27) and GB 7.8% (n\u0026thinsp;=\u0026thinsp;14). There were differences in the distribution of techniques and initial mean lean mass in each diet type (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Differences by sex are shown in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. Differences between surgical techniques are shown in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAnthropometric and body composition variables at baseline stratified by type of protein supplementation\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBody composition variables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLow-protein diet\u003c/p\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;93\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHigh-protein diet n\u0026thinsp;=\u0026thinsp;88\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ep\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eGender (Males/Females) %\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e57.9/48.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e42.1/51.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.77\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eType of surgery (Restrictive techniques/malabsorptive techniques)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e66.6/33.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e88.7/11.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBMI (Kg/m2)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e46.94 (6.01)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e47.41 (.,67)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.62\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal Body Water TBW (Kg)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e46.92 (7.88)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e47.16 (8.88)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.93\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLean mass index LMI (kg/m2)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e23.98 (4.39)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e16.89 (4.38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFat mass index FMI (Kg/m2)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e22.09 (5.01)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e21.65 (5.88)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.87\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAppendicular skeletal muscle mass index ASMMI (kg/m2)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e9.64 (1.32)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e10.32 (1.21)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.35\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eResistance (ohm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e436.11 (63.27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e471.99 (68.19)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.09\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eReactance (ohm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e48.15 (12.51)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e45.08 (6.27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.44\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePhase Angle PA (\u003c/b\u003e◦)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6.55 (1.52)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.35 (1.04)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.74\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eBMI: body mass index; ACT: total body water; LMI: lean mass index; FMI fat mass index; ASMMI: Appendicular skeletal muscle mass index; R: resistance; Rc: reactance; PA: Phase Angle; Kg: kg; cm: centimeters; m: meters; ◦: Angle\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAnthropometric and body composition variables at the beginning of the study stratified by type of protein supplementation and surgical technique\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eBody composition variables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eLow-protein diet\u003c/p\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;93\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003ep\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eHigh-protein diet n\u0026thinsp;=\u0026thinsp;88\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003ep\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRestrictive techniques n\u0026thinsp;=\u0026thinsp;62\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMixed/malabsorptive techniques n\u0026thinsp;=\u0026thinsp;31\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eRestrictive techniques n\u0026thinsp;=\u0026thinsp;78\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eMixed/malabsorptive techniques n\u0026thinsp;=\u0026thinsp;10\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eGender (Males/Females)%\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e29.1/70.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e48.4/51.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e30.7/69.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0/100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBMI (Kg/m\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e46.03 (5.86)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e48.76 (6.01)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e47.65 (6.75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e45.59 (6.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.34\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal body w\u0026aacute;ter TBW (Kg)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e45.66 (6.91)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e51.22 (9.75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e49.09 (9.39)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e42.34 (5.80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.21\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLean mass index LMI (kg/m\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e23.43 (3.78)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e24.89 (5.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e15.81 (4.54)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e20.12 (1.89)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.12\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFat mass index FMI (kg/m\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e21.94 (5.45)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e22.36 (4.43)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e22.81 (5.51)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e19.34 (8.11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.66\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAppendicular skeletal muscle mass index ASMMI (kg/m\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e9.39 (1.26)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e10.48 (1.18)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e9.13 (1.65)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e10.72 (1.12)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.34\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eResistance (ohm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e448.29 (63.76)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e349.70 (41.83)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e459.06 (67.56)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e504.30 (67.17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.30\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eReactance (ohm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e48.49 (9.06)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e46.96 (21.31)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e43.77 (6.97)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e49.01 (7.32)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.58\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePhase Angle PA (\u003c/b\u003e◦)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6.34 (1.08)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7.42 (2.56)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e6.60 (1.12)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.60 (2.87)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.51\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003eBMI: body mass index; TBW: total body water; LMI: lean mass index; FMI: fat mass index; ASMMI: Appendicular skeletal muscle mass index; R: resistance; Rc: reactance; PA: Phase Angle; Kg: kg; cm: centimeters; m: meters; ◦: Angle\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eChanges in Anthropometric Variables\u003c/h3\u003e\n\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e describes the anthropometric variables before surgery, as well as changes at one and six months according to diet type.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eEvolution of anthropometric and body composition variables stratified by type of protein supplementation\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eBody composition variables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003eLow-protein diet\u003c/p\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;93\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003ep\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003eHigh-protein diet n\u0026thinsp;=\u0026thinsp;88\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003ep\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePre-surgery\u003c/p\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;93\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 mes n\u0026thinsp;=\u0026thinsp;88\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6 months n\u0026thinsp;=\u0026thinsp;82\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ePresurgery n\u0026thinsp;=\u0026thinsp;88\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1 mes n\u0026thinsp;=\u0026thinsp;87\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e6 months n\u0026thinsp;=\u0026thinsp;85\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eWeight (Kg)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e130.55 (24.03)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e112.65 (20.51)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e100.44 (19.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e129.40 (26.39)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e115.29 (24.63)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e103.84 (22.72)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBMI Kg/m\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e47.26 (5.89)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e40.82 (5.35)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e36.40 (5.21)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e47.35 (6.69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e42.31 (6.67)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e38.25 (6.48)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal body water TBW (Kg)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e45.81 (7.75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e43.89 (7.41)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e44.36 (6.12)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e47.21 (12.13)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e47.08 (9.83)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e45.73 (9.06)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.59\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLean mass index LMI (kg/m\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e24.03 (4.52)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e22.67 (4.12)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e21.08 (3.56)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e16.23 (4.29)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e16.54 (3.79)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e16.27 (4.02)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.67\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFat mass index FMI (kg/m\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e22.76 (2.51)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e19.19 (2.75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e16.36 (3.76)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e24.19 (5.84)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e19.68 (3.41)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e15.18 (4.21)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAppendicular skeletal muscle mass index ASMMI (kg/m\u003c/b\u003e\u003csup\u003e\u003cb\u003e2\u003c/b\u003e\u003c/sup\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e9.63 (1.54)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e8.95 (1.22)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e8.81 (1.09)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e10.28 (1.48)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e9.78 (1.24)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e8.61 (1.06)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eResistance (ohm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e441.83 (65.88)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e447.17 (74.07)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e433.73 (70.63)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e487.77 (89.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e452.33 (77.91)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e432.41 (73.23)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.22\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eReactance (ohm)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e50.92 (14.50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e47.75 (13.81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e45.83 (11.46)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e44.83 (7.65)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e51.30 (10.11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e46.45 (10.62)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.38\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePhase PA (\u003c/b\u003e◦)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6.75 (2.46)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6.28 (1.74)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5.83 (1.04)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e6.20 (1.22)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e7.04 (1.64)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e6.41 (1.26)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e \u003cp\u003e0.07\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"9\"\u003eBMI: body mass index; TBW: total body water; LMI lean mass index; FMI: fat mass index; ASMMI: Appendicular skeletal muscle mass index; R: resistance; Rc: reactance; PA: Phase Angle; Kg: kg; cm: centimeters; m: meters; ◦: Angle\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThere was a mean weight loss in the first month of 12.11 (5.84) %; 13.18 (5.21) kg in men; 11.49 (6.03) kg in women (p\u0026thinsp;=\u0026thinsp;0.03). The mean weight loss at six months was 21.16 (8.09) %; 23.76 (7.68) kg in men and 19.84 (7.99) kg in women (p\u0026thinsp;=\u0026thinsp;0.01). There was a significant loss of weight and BMI in both groups (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe percentage of weight loss one month after metabolic and bariatric surgery was 13.44% (6.71%) in the LPD group and 10.78% (4.45%) in the HPD group, with statistically significant differences (p\u0026thinsp;=\u0026thinsp;0.01). The percentage of weight loss at six months was 22.89% (8.78%) in the LPD group and 19.49% (7.01%) in the HPD group, also with significant differences (p\u0026thinsp;=\u0026thinsp;0.01).\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eChanges in Bioimpedance Parameters\u003c/h2\u003e \u003cp\u003eAfter the first month post-surgery, there was an increase in resistance in both groups, with no significant differences (+\u0026thinsp;5.33 (29.59) LPD vs. +4.83 (52.10) HPD, p\u0026thinsp;=\u0026thinsp;0.29), as well as a loss of reactance (-3.17 (17.06)) and phase angle (-0.48 (2.13)) in LPD and a gain in HPD (+\u0026thinsp;6.47 (6.27); +0.83 (1.11)), although without reaching statistical significance.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows the differences in body composition between groups. Maintenance of lean mass index is observed in HPD and a loss in LPD. At six months post-surgery, there was a more marked loss of resistance and reactance in LPD, as well as a gain in phase angle in HPD and a loss in LPD, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e3\u003c/span\u003e. There was a loss of total body water, fat mass index, and appendicular skeletal muscle mass index at six months, similar in both groups. The loss of lean mass was greater in the LPD group (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003ePatients who received protein supplementation with a normocaloric, high-protein oral nutritional supplement to complete their caloric-protein requirements during the first two weeks after metabolic and bariatric surgery maintained phase angle and lean mass index to a greater extent than those patients without supplementation. Weight loss was greater in the group without protein supplementation; however, fat mass loss was similar between both groups in the first six months after surgery.\u003c/p\u003e \u003cp\u003eBaseline characteristics between both groups were similar, except for a higher representation of malabsorptive techniques in the LPD group and a higher lean mass index in this group. When stratified by surgical technique, there were no baseline differences in the HPD group, while in the LPD group, patients who underwent malabsorptive techniques started with a higher appendicular skeletal muscle mass index and lower reactance than those with restrictive techniques. Female sex was the most prevalent in all groups.\u003c/p\u003e \u003cp\u003eWeight loss was greater in the LPD group, although both groups showed significant weight and BMI loss over time. Some studies indicate that weight loss after surgery in patients who received protein supplementation does not differ significantly from those without postoperative protein supplementation (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e). Other studies show a positive correlation between weight loss and protein intake (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e). Meanwhile, other authors report more pronounced weight loss in patients without protein supplementation (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e), as in our study, probably related to loss of fat-free mass.\u003c/p\u003e \u003cp\u003eProgressive diets restricted in protein, intolerance to protein secondary to reduced gastric chamber, and malabsorption from techniques that modify the duodenum result in nearly half of patients not consuming the recommended protein intake after surgery (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e). The effect of protein supplementation on the maintenance of fat-free mass is controversial. Some studies support the hypothesis that protein supplementation improves or maintains fat-free mass after surgery (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e), while others do not support this hypothesis (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e). Ranjbar et al. (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e), in a recent meta-analysis of 10 randomized clinical trials with patients undergoing mixed and malabsorptive techniques, concluded that the group with protein supplementation maintained muscle mass (1.33 kg, 95% CI: 0.1 to 2.57, p\u0026thinsp;=\u0026thinsp;0.035), fat-free mass (1.74 kg, 95% CI: 0.46 to 3.01, p\u0026thinsp;=\u0026thinsp;0.01), and lost fat mass (-3.91 kg, 95% CI: -4.10 to -0.59, p\u0026thinsp;=\u0026thinsp;0.01) to a greater extent than the control group, results similar to those obtained in our study.\u003c/p\u003e \u003cp\u003eThe type of protein supplementation has also been evaluated to determine the most suitable protein type. It is postulated that supplementation with short peptides may be better tolerated due to their smaller size and greater ease of absorption (\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e). Comas et al. (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e), in a study with GB patients, used short peptides, complex peptides, or a supplement enriched with hydroxymethylbutyrate (HMB). Fat-free mass one month after surgery was better maintained in patients with short peptides (40.60\u0026thinsp;\u0026plusmn;\u0026thinsp;17.27 in complex protein supplementation, 34.57\u0026thinsp;\u0026plusmn;\u0026thinsp;13.15 kg in HMB, and 19.14\u0026thinsp;\u0026plusmn;\u0026thinsp;9.38 kg in short peptide supplementation, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The supplement in our study contained whey protein, calcium caseinate, was enriched in L-leucine, and contained the probiotic Bifidobacterium animalis. The use of probiotics after MBS has been previously studied, relating their use to greater weight loss, lower caloric intake, and improvement in lipid and hepatic profiles (\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe surgical technique may be one of the factors influencing body composition and weight loss after surgery. In our study, SG was the most common technique, although patients with malabsorptive techniques started with a higher ASMMI, without other baseline differences. Maintenance of fat-free mass with protein supplementation has been described for both restrictive (\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e) and malabsorptive (\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e) techniques.\u003c/p\u003e \u003cp\u003eFinally, it is worth mentioning the maintenance of phase angle in patients who received protein supplementation. The decrease in phase angle after MBS seems to have a paradoxical value, as excessive weight loss reduces comorbidities associated with obesity and improves health; however, a low phase angle is associated with malnutrition and/or nutritional risk. Previous studies have associated the decrease in phase angle after surgery with loss of visceral protein mass, muscle mass, and worsening of protein nutritional status (\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e). In our sample, significant maintenance of phase angle occurred from six months onward, in line with findings from other studies (\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThis study has several limitations that should be considered when interpreting its results. First, it is a retrospective cohort study, which implies possible selection bias and a lower capacity to establish causal relationships. In addition, the comparison between groups was made with a historical cohort, which may introduce uncontrolled variability in the intervention, follow-up, or outcome assessment. Randomization of participants was not performed, limiting homogeneity between groups and possibly influencing the baseline differences observed, especially in the type of surgical technique and initial lean mass index. Adherence to protein supplementation was not systematically recorded, nor was gastrointestinal tolerance documented, both key aspects in this type of intervention. Another relevant limitation is the absence of quantitative recording of physical activity during follow-up, a variable that may influence lean mass evolution. Finally, some body composition parameters were estimated from validated equations, which implies indirect inference and possible margin of error, especially in patients with morbid obesity.\u003c/p\u003e \u003cp\u003eAmong the main strengths of this work are the relatively large sample size and the inclusion of patients undergoing different surgical techniques, allowing for a more representative evaluation of routine clinical practice. The six-month follow-up provides relevant information on medium-term changes in body composition after metabolic and bariatric surgery. Likewise, the use of multifrequency bioimpedance allows for a detailed assessment of body compartments such as lean mass index, phase angle, or appendicular skeletal muscle mass index. The nutritional intervention was applied by qualified personnel with specific training, ensuring greater uniformity in dietary education and initial follow-up. Finally, the study provides evidence on the impact of early protein supplementation on the maintenance of lean mass and functional parameters, which may help optimize nutritional management in the immediate postoperative period of patients with obesity undergoing bariatric surgery.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThe administration of a normocaloric, high-protein oral nutritional supplement during the first weeks after metabolic and bariatric surgery was associated with greater preservation of lean mass index and phase angle, without compromising medium-term fat mass loss. Although the group without supplementation showed greater total weight loss, this difference could be attributed to a greater reduction in fat-free mass, which may have negative implications for patient functionality and nutritional status. These findings highlight the importance of an adequate nutritional strategy in the immediate postoperative period, especially aimed at meeting protein requirements. Early supplementation could represent an effective and safe intervention to minimize muscle catabolism and improve the quality of weight loss. Future prospective and randomized studies will be necessary to confirm these results and establish individualized recommendations according to surgical technique and baseline patient characteristics.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eConflicts of interest:\u003c/h2\u003e \u003cp\u003ethere are no conflicts of interest to declare.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eConceptualization, J.J.L.-G. and BRB; Data curation, ., B.R.B. and J.G.-G.; Formal analysis, BRB.; Investigation, J.J.L.-G., B.R.-B., D.P.-M., R.J.S, MSV,PPL.-G., E.L.A., D.P.-S. and P.P.-F.; Methodology, J.J.L.-G. and D.A.D.L.-R. and BRB; Resources, BRB. and D.A.D.L.-R.; Software, J.J.L.-G.; Validation, J.J.L.-G. and D.A.D.L.-R.; Writing\u0026mdash;original draft, BRB.; Writing\u0026mdash;review and editing, J.J.L.-G. and D.A.D.L.-R. 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Clin Nutr ESPEN. 2022;52:138\u0026ndash;43. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.clnesp.2022.10.018\u003c/span\u003e\u003cspan address=\"10.1016/j.clnesp.2022.10.018\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNavarro-Marroco J, Hern\u0026aacute;ndez-S\u0026aacute;nchez P, Victoria-Montesinos D, Barcina-P\u0026eacute;rez P, Lucas-Abell\u0026aacute;n C, Garc\u0026iacute;a-Mu\u0026ntilde;oz AM. Comparative Effects of Sleeve Gastrectomy vs. Roux-en-Y Gastric Bypass on Phase Angle and Bioelectrical Impedance Analysis Measures: A Systematic Review and Meta-Analysis. J Clin Med. 2024;13(22):6784. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3390/jcm13226784\u003c/span\u003e\u003cspan address=\"10.3390/jcm13226784\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"metabolic and bariatric surgery, protein supplementation, high-protein diet, body composition","lastPublishedDoi":"10.21203/rs.3.rs-7951468/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7951468/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eIntroduction:\u003c/h2\u003e \u003cp\u003eProgressive diets after metabolic and bariatric surgery that are restricted in protein, protein intolerance, and malabsorption from techniques that exclude the duodenum result in nearly half of patients not consuming the recommended protein intake after surgery.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA cohort study was designed with 181 patients who underwent sleeve gastrectomy, gastric bypass, and biliopancreatic diversion. Eighty-eight patients (prospective cohort) received a progressive diet with a normocaloric, high-protein oral nutritional supplement during the first two weeks after surgery (817 kcal, 65.7 g protein/day). A historical cohort of 93 patients treated with a standard progressive diet (217 kcal, 11.7 g protein/day). Anthropometric and body composition data were analyzed before surgery, and at 1 and 6 months post-surgery.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003epercentage of weight loss was observed in patients on the low-protein diet (LPD) at one month (LPD 13.44% (6.71%) vs. high-protein diet (HPD) 10.78% (4.45%); p\u0026thinsp;\u0026lt;\u0026thinsp;0.01) and at six months (LPD 22.89% (8.78%) vs.HPD 19.49% (7.01%); p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). There was maintenance of lean mass index (LPD \u0026minus;\u0026thinsp;1.37 (0.69) kg vs.HPD\u0026thinsp;+\u0026thinsp;0.31 (0.79) kg; p\u0026thinsp;=\u0026thinsp;0.01) in HPD patients at one month, with no differences in fat mass loss. At six months, there was less loss of lean mass index (LPD \u0026minus;\u0026thinsp;2.75 (2.01) kg vs.HPD \u0026minus;\u0026thinsp;1.24 (2.06) kg; p\u0026thinsp;=\u0026thinsp;0.00) and phase angle (LPD \u0026minus;\u0026thinsp;1.25 (51.77) kg vs. HPD\u0026thinsp;+\u0026thinsp;0.83 (0.12) kg; p\u0026thinsp;=\u0026thinsp;0.01) in HPD patients.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003ePatients on HPD showed maintenance of lean mass index and phase angle compared to those on LPD during the first six months after bariatric surgery.\u003c/p\u003e","manuscriptTitle":"Effect on Body Composition of Protein Supplementation During the First Six Months After Bariatric Surgery","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-22 09:15:27","doi":"10.21203/rs.3.rs-7951468/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"68ee0517-4be1-4df9-8470-296c67c91968","owner":[],"postedDate":"December 22nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-01-11T17:53:56+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-22 09:15:27","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7951468","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7951468","identity":"rs-7951468","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}