The association between dietary acid load and endometriosis: a case-control study

Background Endometriosis is a chronic inflammatory disorder that affects 5–15% of women of reproductive age. It is characterized by severe symptoms, including dysmenorrhea and non-cyclic pelvic pain, which can substantially impair quality of life. Although diet is a major modifiable risk factor for many chronic diseases, its potential role in endometriosis has received limited attention. This study aimed to investigate the association between Dietary Acid Load (DAL) and the odds of endometriosis among Iranian women.

This hospital-based case-control study was conducted in Tehran, Iran, between February to September 2021. Participants included women diagnosed with endometriosis and healthy controls, all of whom were evaluated by a gynecologist who was blinded to the study object. Dietary intake was assessed using a validated 168-item food frequency questionnaire (FFQ). DAL was estimated using Two indices: Potential Renal Acid Load (PRAL) and Net Endogenous Acid Production (NEAP). Logistic regression models were used to investigate the association between DAL and odds of endometriosis.

A total of 105 women with endometriosis and 208 healthy controls were included in the study. The results showed that each one-unit increase in PRAL and NEAP was associated with an 8%, and 4% increase in the odds of endometriosis, respectively.

Higher DAL was associated with increased odd of endometriosis. These findings suggest that reducing the consumption of acid-producing foods may help lower the risk of endometriosis. Further prospective studies are warranted to confirm these findings and clarify the underlying mechanisms. Similar content being viewed by others

We sincerely thank all field investigators, staff, and participants of the present study. Funding No funding. Author information Authors and Affiliations Corresponding authors Ethics declarations Ethics approval and consent to participate This study was approved by Medical Ethical Committee of National Nutrition and Food Technology Research Institute of Shahid Beheshti University of Medical Sciences (IR.SBMU.NNFTRI.REC.1399.062), in Iran, according to the Declaration of Helsinki. All of the participants provided written informed consent. Data confidentiality was also ensured. Consent for publication Not applicable. Competing interests The authors declare no competing interests. Additional information Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Supplementary Information Rights and permissions Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/. About this article Cite this article Noormohammadi, M., Ghoreishy, S.M., Ghasemisedaghat, S. et al. The association between dietary acid load and endometriosis: a case-control study. BMC Women's Health (2026). https://doi.org/10.1186/s12905-026-04643-4 Received: Accepted: Published: DOI: https://doi.org/10.1186/s12905-026-04643-4