Dietary changes could reduce the pain of endometriosis for half of those suffering from the disease, suggests the largest international survey ever conducted on diet and this condition and involving nearly 2 600 women.
The researchers found that 45% of those who stopped eating gluten and 45% of those who cut out dairy experienced improvement in their pain.
When they cut down on coffee or other caffeine in their diet, 43% of the 2 599 women said their pain was reduced, while 53% who cut back on alcohol reported the same.
Philippa Saunders, senior author of the study and professor of reproductive steroids at the University of Edinburgh, told The Guardian: “It really feels as if we are on the cusp of something pretty big with understanding how diet affects endometriosis symptoms.”
Endometriosis occurs when cells similar to those in the lining of the womb grow in other parts of the body. It affects one in 10 women of reproductive age in the United Kingdom.
However, there is very little research into the causes of the disease or how to treat it – beyond surgery, which is often only a short-term fix, or managing symptoms through hormonal contraceptives like the pill, which many women dislike because of side effects.
It takes an average of almost seven years for women to receive a diagnosis of endometriosis, due to lack of awareness about the disease.
The latest study, led by Edinburgh University and published in the American Medical Association’s JAMA Network Open journal, had asked volunteers about changes to their diet and about dietary supplements used to try to improve their symptoms.
Researchers believe that the women who cut out gluten or dairy and reported feeling less pain may have experienced changes in their gut bacteria.
Reducing caffeine may work because it can affect sleep, and pain often feels worse when people are tired. Cutting back on alcoholic drinks is potentially impactful because alcohol has a similar effect on cells to oestrogen – the hormone fuelling endometriosis.
Endometriosis largely causes pain in the pelvic area, which is often worse during periods, but many sufferers report sciatic pain, with others experiencing breast pain or a flu-like joint pain affecting the whole body.
The womb-like tissue of endometriosis is able to grow new nerve cells – the cells that transmit pain sensations – and make existing nerve cells more active. The pain signals this sends to the brain are increased even more by inflammation, an over-reaction of the immune system. It is this inflammation that could be tackled by dietary changes, experts believe.
Cutting back on certain foods may reduce bacteria in the gut that powers inflammation. The study found almost 40% of respondents reported reduced pain from endometriosis after eliminating processed food like instant meals, ice-cream and sweets, all known to alter gut bacteria.
Almost a third of women said their pain improved after cutting out garlic and onion, which could relieve so-called “endo belly” – uncomfortable bloating sufferers can experience.
The researchers said larger studies, with women randomly assigned to different diets, are still needed to gather compelling evidence on how diet might affect endometriosis, and could include measurements of people’s inflammation and pain.
The Edinburgh study relied on self-reported pain levels and surveyed people from 51 countries, including 1 115 people from the UK.
Francesca Hearn-Yeates, who led the study from the University of Edinburgh, said: “Women are in need of anything that can help with the pain of endometriosis. This condition is so under-researched and there is so much to discover, but there is growing evidence that gut bacteria could play a part in symptoms, which explains why many women have experimented with changing their diets, and why this appears to work for many.”
Jo Hanley, specialist adviser for Endometriosis UK, said: “There is a need for more high-quality evidence but I’ve heard many a success story from women where dietary changes have led to improved pain, although unfortunately others have reported no improvements.
“An anti-inflammatory diet can help reduce the body’s inflammation response, and foods containing refined sugars, carbohydrates, unhealthy fats, dairy, red and processed meats … can create inflammation.”
Study details
Dietary Modification and Supplement Use For Endometriosis Pain
Francesca Hearn-Yeates, Katherine Edgley, Andrew Horne et al.
Published in JAMA Network on 31 March 2025
Introduction
Endometriosis is a neuroinflammatory reproductive disorder defined by the presence of endometrial-like tissue (lesions) outside the uterus that is difficult to diagnose and treat. Chronic pain is a common symptom but patients also have infertility, fatigue, and gastrointestinal (GI) symptoms, including those similar to irritable bowel syndrome and abdominal bloating (colloquially referred to as endo belly). Current treatment options are largely limited to surgery or hormone-suppressive drugs. The gut microbiome has been implicated as a regulator of pain in inflammatory conditions, including endometriosis, and its modification by diet has been explored to manage symptoms. We conducted an online survey to gain insights into which dietary modifications and/or supplements were perceived as beneficial for pain management by individuals with endometriosis.
Methods
This survey study was developed with a local patient support group, was approved by the Edinburgh Medical School Research Ethics Committee, and followed the AAPOR reporting guideline. A 24-question survey was available in English on the online platform, Qualtrics (Qualtrics Ltd), between June 10 and September 2, 2022. Data were analysed using Python 3.0 (Python), and statistical comparisons of distributions were performed using the Mann-Whitney U test. Statistical significance was set at P < .05, and tests were 2-sided. Data were analysed from September 2022 to January 2025.
Results
Among the 2 858 individuals who started the survey, 2 599 completed more than 80% of the questions, and 2388 of these respondents had a confirmed diagnosis of endometriosis (103 Asian respondents [4.3%]; 45 black respondents [1.9%]; 2110 white respondents [88.4%]; mean [range] age, 35.4 [16-71] years). Most respondents reported pelvic pain (2313 [96.9%]) and frequent abdominal bloating (2177 [91.2%]). Notably, 2001 respondents (83.8%) had tried one or more diets to manage their symptoms and 1404 had used supplements (58.8%), with 1339 (66.9%) and 609 (43.4%) considering these self-help strategies had improved their pain, respectively.
When respondents’ pain scores (0 to 10 scale) were represented on a histogram, there was a statistically significant difference between those who reported the modification had improved pain compared with those who did not, with the former having lower pain scores than the latter (median [IQR], 4.0 [3.0-6.0] for respondents reporting improvement from dietary modification vs 5.0 [4.0-7.0] for respondents reporting no improvement; P < .001; 4.0 [3.0-6.0] for respondents reporting improved pain from any supplements vs. 5.0 [4.0-7.0] for respondents reporting no improvement, P < .001) Responses to questions about access to information by survey respondents revealed that the most popular source(s) of advice that prompted a change of dietary habits were from social media or a health care professional. Among the most popular dietary modifications attempted, pain improvement was reported by 666 of 1252 who reduced alcohol (53.2%), 523 of 1151 who reduced gluten (45.4%), 512 of 1132 who reduced dairy (45.2%), and 473 of 1091 who reduced caffeine (43.4%).
The low-Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols diet (ie, FODMAP) was less popular (181 of 563 [32.1%]). Among the 812 respondents who used magnesium, 262 (32.3%) reported a benefit.
Discussion
To our knowledge, this is the largest international survey to date of individuals with endometriosis who have tried diets and/or supplements to manage pain symptoms. A large number of different diets or strategies were reported but it was noted that the most popular involved reduction or elimination of specific items (eg, alcohol, gluten, dairy, caffeine) rather than specific diets, such as the low-FODMAP diet, as previously reported.3,4 These data supported the findings of previous surveys and clinical trials that suggested dietary modifications may help individuals manage pain associated with endometriosis. However, no single modification was uniquely perceived as beneficial, and none of the changes were helpful for some individuals. Limitations of the study include the selection bias of individuals interested in dietary changes and lack of alternative language options and questions regarding the length of diet use and impact on abdominal bloating.
JAMA Network article – Dietary Modification and Supplement Use For Endometriosis Pain (Open access)
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