Endometriosis and Gluten: What the Evidence Actually Says

If you live with endometriosis, you have almost certainly been handed dietary advice you didn’t ask for. Somewhere near the top of that list is “cut out gluten — it fixed mine.” It comes up constantly in support groups, and it comes from a real place: endometriosis pain is severe, it is chronically under-treated, and when medicine leaves you waiting, changing what’s on your plate is one of the few levers that feels like it’s yours.

So this piece is not here to tell you that you’re wrong to look. It’s here to separate the part that is genuinely supported from the part that isn’t — and to flag one piece of practical advice that could save you a great deal of trouble if you do decide to try it.

What’s real: coeliac disease and endometriosis do occur together more often

This bit holds up. A large Swedish study followed 11,097 women with biopsy-confirmed coeliac disease against nearly 55,000 matched controls and found a raised rate of later endometriosis — a hazard ratio of 1.39 (95% CI 1.14–1.70). Smaller studies point the same way: two found coeliac disease in around 2.2–2.5% of women with confirmed endometriosis, against roughly 0.7–0.8% in controls.

But it’s worth seeing the size of it honestly, because “39% higher risk” sounds far more dramatic than the reality. In that Swedish cohort the absolute excess was about 31 extra cases per 100,000 person-years. It’s a real signal, not a looming threat — and a 2019 systematic review of endometriosis and autoimmune conditions cautioned that across this literature the evidence quality is generally poor, with only 5 of 26 studies rated high quality.

The sensible takeaway isn’t alarm. It’s simply this: if you have endometriosis and persistent gut symptoms, coeliac disease is worth ruling out — a conversation with your GP, not a reason to worry.

What isn’t established: that going gluten-free treats endometriosis

This is the claim that outruns its evidence. Almost every version of it traces back to a single Italian study from 2012 (Marziali et al.), which reported that after 12 months gluten-free, 75% of participants said their pain had improved. That sounds persuasive until you look at how it was run:

• There was no control group. It was a retrospective before-and-after study, so there’s nothing to compare against — and pain that fluctuates naturally, or improves simply because someone is paying attention to it, would look identical.
• Nobody was tested for coeliac disease at enrolment. Given the overlap above, some of the people who felt better may simply have been undiagnosed coeliacs finally eating the right diet — which tells us about coeliac disease, not endometriosis.
• The dropouts vanish from the headline. 295 people started; 88 (30%) withdrew within two weeks with abdominal side effects, and only the remaining 207 were analysed. The famous “75%” is 156 of those 207 — not 156 of everyone who tried.
• Diet studies like this are also wide open to placebo and nocebo effects, which are especially strong with gluten specifically.

Two recent reviews looked at the whole picture and landed in the same place. A 2023 review in Frontiers in Nutrition concluded that recommending a gluten-free diet to women diagnosed solely with endometriosis should not be advised. A 2024 paper put it more bluntly still: a gluten-free diet “should be discouraged unless there is an additional diagnosis of nonceliac wheat sensitivity or celiac disease.”

And the evidence isn’t even pointing consistently in one direction: one 2022 analysis found higher gluten intake associated with a lower likelihood of an endometriosis diagnosis. When studies disagree about which way the arrow points, that is usually a sign there’s no strong effect to find.

⚠️ The practical bit: if you’re going to test, test first

This is the part we most want you to take away, because getting the order wrong is genuinely costly.

Coeliac testing only works while you are still eating gluten. Both the blood test and the biopsy look for your body’s reaction to it, so if you’ve already stopped, the tests can come back negative even when you do have coeliac disease. UK guidance (NICE, echoed by Coeliac UK) is to eat gluten in more than one meal a day for at least six weeks before testing, and not to start a gluten-free diet until a specialist confirms the diagnosis — even if your blood test already came back positive.

The trap is easy to fall into: you feel unwell, you cut gluten, you feel a bit better, and months later a doctor can no longer give you a clear answer. Getting the diagnosis matters — it comes with medical follow-up, monitoring, and in many countries practical support that a self-managed diet doesn’t. So if coeliac disease is a possibility for you, ask for the test before you change your diet, not after.

So where does that leave you?

Roughly here:

• Endometriosis plus ongoing gut symptoms? Worth asking your GP about coeliac testing — while still eating gluten.
• Tested positive for coeliac disease? Then a strict gluten-free diet is the treatment, for the coeliac disease. That’s well established and not in question here.
• Endometriosis alone, tests clear? The current evidence doesn’t support going gluten-free as a treatment for it, and a long-term restrictive diet carries its own costs — expense, hassle, and a risk to overall diet quality without proper guidance.
• Tried it and genuinely feel better? Your experience isn’t invalid. But it’s worth exploring with a clinician or dietitian what’s actually driving it — FODMAPs, wheat sensitivity, or something else — rather than assuming gluten is the answer.

None of this is medical advice, and none of it is a verdict on your body. It’s the state of the evidence as of 30 July 2026, laid out so you can take it into a conversation with someone who knows your history.

Sources, checked 30 July 2026: Stephansson et al., “Risk of endometriosis in 11,000 women with celiac disease”, Human Reproduction 2011 · Marziali et al., Minerva Chirurgica 2012 · Frontiers in Nutrition 2023 · “A gluten-free diet for endometriosis patients lacks evidence to recommend it” (2024) · NICE NG20 and Coeliac UK on getting diagnosed. If any of this moves, tell us and we’ll re-check.