The Effect of Bariatric Surgery on Nutritional Status and Biochemical Parameters: A Longitudinal Study

This study was conducted to determine the nutrition and biochemical parameters of patients who underwent bariatric surgery at the preoperative stage and then followed up postoperatively at four-month, and eight-month intervals. A prospective longitudinal study was carried out with 37 obese patients (27 females, 10 males) who underwent sleeve gastrectomy (SG) at a private hospital between July 2021 and March 2022. Demographic characteristics, dietary intake, and some biochemical parameters of the patients aged between 19-64 years who underwent SG surgery were examined at the preoperative 0th month, postoperative 4th month, and 8th-month stage. The mean age was 34.78±9.52 years. When analyzing the 24-hour food intake carbohydrate intake showed a statistically significant relationship with gender and month of follow-up (p<0.05). Additionally, the protein, fat, total fiber, saturated fatty acid, polyunsaturated fatty acid, and monounsaturated fatty acid intakes for female participants showed a statistically significant relation to the month of follow-up (p<0.05). Body weight and BMI were statistically significant in relation to gender and month (p<0.05). Biochemical findings showed that fasting blood glucose, uric acid, ALT, GGT, triglyceride, TSH, and B12 vitamin levels were statistically significant according to gender and months of follow-up (p<0.05). Moreover, the creatinine, AST, HDL cholesterol, and free T4 levels of women were statistically significant in relation to months of follow-up (p<0.05). This study suggests that bariatric surgery has a positive effect on nutrition status and metabolic parameters. This leads to a reduction in oxidative damage in patients, thereby reducing the risk of the development and progression of multiple obesity-related comorbidities.