Don’t put yourself through unnecessary suffering, relying on ‘natural’ supplements to manage your endometriosis pain. Experts searched high and low for trustworthy clinical trials that showed they work and were disappointed by the results.
I absolutely do not expect you to take my word for it! You shouldn’t!
Instead, come with me and have a look at the results of a meta-analysis performed last year by Italian endometriosis experts based at the University of Milan. If you are champing at the bit to see what they unearthed, skip to the findings here.
Don’t Trust Unregulated Sources
Alternative ‘medicine’ grifters are at it again. With endometriosis finally receiving much needed attention, people with zero medical expertise are hopping on the band wagon to sell you expensive supplements. Herbal remedies are not all bunk. After all, that’s where the first drugs came from and we are still finding plant-based molecules that are absolutely useful for all kinds of illnesses. With that said, disappointingly, doctors have yet to uncover a dietary supplement that genuinely helps women to manage their painful endometriosis symptoms.
Do diindolylmethane, milk thistle, N-acetyl cysteine, vitamin C, ginger, magnesium glycinate, vitamin D, garlic, curcumin (turmeric), lactobacillus, resveratrol, fish oils or melatonin help with endometriosis pain? Sadly, they probably won’t. Will they do you any harm? Not if they come directly from the food you eat, but it’s not the chemicals in garlic that are the danger here. It’s the people giving it to you. The worry with ‘natural’ supplements comes in three varieties:
First, in most countries, the pills and powders are not regulated and might not be what you think they are. It’s not just a case of careless factory preparation accidentally changing doses or accidentally mixing up identical bottles. Sometimes, unscrupulous manufacturers sneak in real drugs to make you feel like something is happening. These drugs are not always on the label, they can stop your real medications from working and even seriously harm you.
Second, not all alternative medicine practitioners know what they are talking about, and plenty of them have some really troubling beliefs about mainstream medicine. If you are taking advice encouraging you to stop getting mainstream medical treatment or skip hormone therapy in favour of folk remedies or massage, your symptoms will come back, and may even get worse.
The third danger is to your wallet. I don’t know about you, but the sticker shock of $60 for a bottle of garlic extract and turmeric would put me in hospital.
A Fruitless Search
The team searched medical and scientific journal databases for clinical trials or studies that attempted to measure how well ‘natural’ supplements helped women with endometriosis to manage pain. They found 679 articles that claimed to test how well dietary supplements eased pain caused by endometriosis.
Of those 679 papers, only 272 were actually research articles, 25 papers were not available in English translation. This is already a troubling result, only 36% of the papers that made claims about endometriosis pain and natural supplements actually attempted to test them. From there, things went downhill fast.
The endometriosis specialists screened each paper to make sure it would give them useful information. Did the trial only include women and girls who really had endometriosis? Was the study a blinded randomized controlled trial? Did they compare the supplement against a placebo? Did the trial focus on pain caused by endometriosis? Finally were the research articles peer reviewed and published in a genuine medical journal? Did they provide a full description of how they did the experiments and a complete set of numbers to back up their claims?
Nine Papers Made the Cut
Out of 247 research papers, only nine actually tested whether the dietary supplements had any effect on endometriosis associated pain. Nine.
The biggest problems were that the studies included women who did not have a genuine endometriosis diagnosis or did not compare the dietary supplement to something.
Since getting a real endometriosis diagnosis is very difficult, women who have some similar symptoms are often given a clinical diagnosis. The problem with that is that if you are having those pains and other symptoms for another reason, even if from the outside they look the same, if you join the trial, you will derail the results. If you don’t have endometriosis, an endometriosis treatment won’t work on you.
Endometriosis can only be definitively diagnosed by doctors finding endometriosis lesions outside your uterus.
The nine papers in the final cut were all doubled blinded, randomized and placebo controlled. This means that the women and the researchers did not know whether they were getting a real dietary supplement or a sugar pill so nobody could accidentally skew the results due to optimism and enthusiasm. It also allowed the academics to make clear one-to-one comparisons between the treatment and the sham – if there was a difference in pain between the two groups, it would be easy to spot it.
Next they looked at whether the trials were trustworthy. Of the nine trials that only included women who definitely had endometriosis and compared the supplement to a control group, only three reached the standard of experimental design and data presentation that we expect from a trustworthy clinical trial.
The rest? One was written by a researcher who had had 14 papers retracted for faking data or ethical violations and one was funded by a supplement manufacturer. Another started off with differences between the control and experimental group that made comparisons difficult and three more were registered with clinical trial databases very late.
Despite these concerns the researchers still included them in their analysis just in case.
No Supplement Helped Ease Endometriosis Related Pain
The researchers carefully extracted the data from each of the nine papers they featured in their final selection and set about analysing the results. Overall 545 women with endometriosis diagnosed by laparoscopy, transvaginal ultrasound or MRI were included.
They found that dietary or natural supplements tested in the nine trials were: vitamin D, garlic, curcumin (turmeric), lactobacillus, resveratrol, silymarin (milk thistle), fish oils or melatonin. Interestingly, nobody has done a real trial to test diindolylmethane, N-acetyl cysteine, vitamin C, ginger or magnesium glycinate – despite these being the top recommendations of online supplement enthusiasts. Makes you wonder, doesn’t it? Or maybe not. Let’s just say if I did a trial to test one of those and it didn’t work, would I help my supplement sales business by telling people?
The researchers assessed outcomes by looking at pelvic pain (general pelvic pain, painful periods, pain during or after sex), pain catastrophizing and, finally, health-related quality of life. If a supplement eased pain, made women less afraid of the pain or made them feel better in any way, the researchers should be able to spot a difference between the control groups and the treatment groups.
Overall, none of the treatments changed pain scores in women who used the supplements for a minimum of eight weeks, compared to women who got a placebo.
Endometriosis Pain vs Supplements
The researchers observed that none of the supplements trialled improved women’s pain scores compared to placebo, either individually or overall. Based on the numbers of women included and the trustworthiness of the papers, the team concluded that there was moderate evidence to support this conclusion. Only milk thistle seemed to show a small improvement.
When they looked at painful periods, AKA dysmenorrhoea, they saw similar results. Overall, dietary supplements didn’t improve pain scores. But part of the reason the stats didn’t show much was that the results were all over the place, and it looks like a lot of negative results were not submitted for publication.
One study was skewing the results. Taking it it out showed a very small improvement in pain scores for the treatments, but given only 3/9 studies were ‘trustworthy’, the team concluded this was weak evidence. Vitamin D seemed like it might help a little but both of these studies were ones that scored lower on trustworthiness because the authors registered the clinical trials after they had started them. This is a hint that they might have cherry-picked results.
Similar to pelvic pain, dyspareunia – pain during and after sex, was not helped by dietary supplements.
The researchers also didn’t see any benefit in terms of pain catastrophizing, or quality of life improvement after taking the supplements.
Why is Nobody Testing?
There is no evidence that dietary supplements help endometriosis yet. Don’t get me wrong. If a clinical trial showed a dietary supplement or herbal medicine helped endometriosis, I would be first on the party bus. My problem is, if they work, why aren’t the makers showing us the proof?
The most important finding by the authors is not necessarily that omega-3 and turmeric don’t help ease endometriosis pain. It’s that so few real trials are being run to test these supplements. Over 600 articles in the scientific literature highlight supplements for endometriosis, but only nine of them were real clinical trials, and of those, three met minimum standards for trustworthiness. That’s a real issue.
Right now it’s incredibly hard to get an endometriosis diagnosis because it’s hidden inside our body, and so many tests are indirect measures. For similar reasons, scientists are still struggling to figure out what this condition really is. This means it’s very important that we use evidence-based methods to choose treatments. If we don’t know what causes endometriosis, and we also don’t know much about what drives the pathology, we can’t make guesses about potential treatments based on disease mechanisms.
Think about it. If we are taking bioactive herbal supplements that do ‘stuff’, how can we know whether those supplements are helping or harming? It’s one thing if they don’t do anything – it’s just a waste of money, but what if they make the lesions worse?
Bottom line, talk to the MD treating your endometriosis before you invest in ‘natural’ supplements. They have background education about biology of disease and how your hormones work, that alternative medicine practitioners skipped. Perhaps there are supplements that will do you good, but only a pharmacist or a specialist will know which ones are safe to mix with your meds.
Read the original study here
Salmeri N, Ragusi A, Buffo C, Somigliana E, Viganò P, Vercellini P. Dietary Supplements for Endometriosis-Associated Pain: A Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Trials. Gynecol Obstet Invest. 2026;91(1):101-114. doi:10.1159/000545414
