How to Treat Endometriosis with Diet

“Endometriosis is a major cause of disability and compromised quality of life in women and teenage girls.” It “is a chronic disease which is under-diagnosed, under-reported, and under-researched…[and for patients, it] can be a nightmare of misinformation, myths, taboos, lack of diagnosis, and problematic hit-and-miss treatments overlaid by a painful, chronic, stubborn disease.”

Pain is what best characterizes the disease: pain, painful intercourse, heavy irregular periods, and infertility. About one in a dozen young women suffer from endometriosis, and it accounts for about half the cases of pelvic pain and infertility. It’s caused by what’s called “retrograde menstruation”—blood, instead of going down, goes up into the abdominal cavity, where tissue of the uterine lining can implant onto other organs. The lesions can be removed surgically, but the recurrence rate within five years is as high as 50 percent.

Endometriosis is an estrogen-dependent disease, so might the anti-estrogenic effects of the phytoestrogens in flaxseeds and soy foods help, as they appear to do in breast cancer? I couldn’t find studies on flax and endometriosis, but soy food consumption may indeed reduce the risk of that disease. What about treating endometriosis with soy? While I couldn’t find any studies on that, there is another food associated with decreased breast cancer risk: seaweed.

Seaweeds have special types of fiber and phytonutrients not found in land plants, so in order to get these unique components, we would need to incorporate sea vegetables into our diet. Seaweeds, may have anti-cancer properties, including anti-estrogen effects. Japanese women have among the lowest rates of breast, endometrial, and ovarian cancers, as well as longer menstrual cycles and lower estrogen levels circulating in their blood, which may help account for their low risk of estrogen-dependent cancers. We assumed this was due to their soy-rich diets, but their high intake of seaweed might also be helping.

When seaweed broth was dripped on human ovary cells that make estrogen, estrogen levels dropped. Why? It either inhibits production or facilitates breakdown of estrogen. It may even block estrogen receptors, lowering the activity of the estrogen that is produced. This is in a petri dish, though. Does it happen in women, too? Yes.

Researchers estimated that an effective estrogen-lowering dose of seaweed for an average American woman might be around five grams a day, but, apparently, no one has tried testing it on cancer patients yet. However, it has been tried on endometriosis, as I discuss in my video How to Treat Endometriosis with Seaweed.

Three women with abnormal menstrual cycles, including two with endometriosis, volunteered to add a tiny amount of dried, powdered bladderwrack, a common seaweed, to their daily diet. This effectively lengthened their cycles and reduced the duration of their periods—and not just by a little. As you can see at 3:14 in my video, subject 1 had a 30-year history of irregular periods, averaging every 16 days. Taking just a quarter-teaspoon of this seaweed powder a day added 10 days onto her cycle, up to 26 days, and adding a daily half-teaspoon increased her cycle to 31 days, nearly doubling its length. Furthermore, as you can see at 3:38 in my video, all three women experienced marked reductions in blood flow and a decreased duration of menstruation. For 30 years, subject 1 had been having her period every 16 days, and it typically lasted 9 days. Can you imagine? Then, by just taking a daily half-teaspoon of seaweed, her period came just once a month and only lasted about four days. Most importantly, in the two women suffering from endometriosis, they reported “substantial alleviation” of their pain. How is that possible? There was a 75 percent drop in estrogen levels after just a quarter-teaspoon of seaweed powder a day and an 85 percent drop after a half-teaspoon. 

Of course, with just a few women and no control group in that study, we need bigger, better studies. But, that study was published more than a decade ago and not a single such study has been published since. Millions of women are suffering with these conditions. Does the research world just not care about women? The more pointed question is: who’s going to fund the work? Less than a teaspoon of seaweed costs less than five cents, so a larger study may never be done. But, without any downsides, I suggest endometriosis sufferers give it a try.


For more on endometriosis, see my video What Diet Best Lowers Phthalate Exposure?, and, to learn about the anti-estrogenic effects of the phytoestrogens in flaxseeds on breast cancer, see Flaxseeds and Breast Cancer Survival: Clinical Evidence.

Interested in more on sea vegetables? See:

I recommend staying away from kelp and hijiki, though. Why? See Too Much Iodine Can Be as Bad as Too Little.

Learn more about other natural remedies for menstrual problems:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

What to Eat and Avoid for Women with BRCA Gene Mutations

Five studies have been performed on breast cancer survival and soy foods involving more than 10,000 breast cancer patients, and together they found that those who eat more soy live longer and have a lower risk of the cancer coming back. What about women who carry breast cancer genes? Fewer than 10 percent of breast cancer cases run in families, but when they do, it tends to be mutations to one of the tumor suppressor genes, BRCA1 or BRCA2. BRCA 1 and BRCA 2 are involved in DNA repair, so if either one of them is damaged, chromosomal abnormalities can result, which can set us up for cancer. I examine this in my video Should Women at High Risk for Breast Cancer Avoid Soy?.

This idea that we have tumor suppressor genes goes back to famous research from the 1960s that showed that if we fuse together a normal cell with a cancer cell, rather than the cancer cell turning the normal cell malignant, the normal cell actually suppresses the cancerous one. Tumor suppressor genes are typically split into two types: gatekeeper genes that keep cancer cells in check and caretaker genes that prevent the cell from becoming cancerous in the first place. BRCA genes appear able to do both, which is why their function is so important.

Until recently, dietary recommendations for those with mutations to BRCA genes focused on reducing DNA damage caused by free radicals by eating lots of antioxidant-packed fruits and vegetables. If our DNA repair capacity is low, we want to be extra careful about damaging our DNA in the first place. But what if we could also boost BRCA function? In my video BRCA Breast Cancer Genes and Soy, I showed how, in vitro, soy phytoestrogens could turn back on BRCA protection suppressed by breast cancer, upregulating BRCA expression as much as 1,000 percent within 48 hours.

Goes that translate out of the petri dish and into the person? Apparently so. Soy intake was associated with only a 27 percent breast cancer risk reduction in people with normal BRCA genes, but a 73 percent risk reduction in carriers of BRCA gene mutations. So, a healthy diet may be particularly important for those at high genetic risk. Meat consumption, for example, was linked to twice as much risk in those with BRCA mutations: 97 percent increased risk instead of only 41 percent increased breast cancer risk in those with normal BRCA genes. So, the same dietary advice applies to those with and without BRCA mutations, but it’s more important when there’s more risk.


What about women without breast cancer genes or those who have already been diagnosed? See my video Is Soy Healthy for Breast Cancer Survivors?.

What is in meat that may increase risk? See:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

The Difference Between Alpha and Beta Receptors Explain Soy’s Benefits

“[S]oyfoods have become controversial in recent years…even among health professionals…exacerbated by misinformation found on the Internet.” Chief among the misconceptions is that soy foods promote breast cancer because they contain a class of phytoestrogen compounds called isoflavones, as I explore in my video, Is Soy Healthy for Breast Cancer Survivors? Since estrogens can promote breast cancer growth, it is natural to assume that phytoestrogens might, too, but most people do not realize there are two different types of estrogen receptors in the body, alpha and beta. Unlike actual estrogen, soy phytoestrogens “preferentially bind to and activate ERβ,” estrogen receptor beta. “This distinction is important because the [two types of receptors] have different tissue distributions within the body and often function differently, and sometimes in opposite ways. This appears to be the case in the breast,” where beta activation has an anti-estrogenic effect, inhibiting the growth-promoting effects of actual estrogen—something we’ve known for more than ten years.

The effects of estradiol, the primary human estrogen, on breast cells are “completely opposite” to those of soy phytoestrogens, which have “antiproliferative effects on breast cancer cells…even at [the] low concentrations” we get in our bloodstream after eating just a few servings of soy. This makes sense, given that after eating a cup of soybeans, the levels in our blood cause significant beta receptor activation, as you can see at 1:27 in my video.

Where did this outdated notion that soy could increase breast cancer risk come from? The concern was based largely on research that showed that the main soy phytoestrogen, genistein, stimulates the growth of mammary tumors in a type of mouse—but, it turns out, we’re not mice. We metabolize soy isoflavones very differently from rodents. As you can see at 2:00 in my video, the same soy phytoestrogens led to 20 to 150 times higher levels in the bloodstream of rodents. The breast cancer mouse in question had 58 times higher levels. What does this mean for us? If we ate 58 cups of soybeans a day, we could get some significant alpha activation, too, but, thankfully, we’re not hairless athymic ovariectomized mice and we don’t tend to eat 58 cups of soybeans a day.

At just a few servings of soy a day, with the excess beta activation, we would assume soy would actively help prevent breast cancer. And, indeed, “[s]oy intake during childhood, adolescence, and adult life were each associated with a decreased risk of breast cancer.” Those women who ate the most soy in their youth appeared to grow up to have less than half the risk. This may help explain why breast cancer rates are so much higher in the United States than in Asia, where soy foods are more commonly consumed. Yet, when Asians come to the United States and start eating and living like Americans, their breast cancer risk shoots right up. Women in their 50s living in Connecticut, for example, are way at the top of the breast cancer risk heap, as you can see at 3:00 in my video, and have approximately ten times more breast cancer than women in their 50s living in Japan. It isn’t genetic, however. When Japanese women move to the United States, their breast cancer rates go up generation after generation as they assimilate into American culture.

Are the anti-estrogenic effects of soy foods enough to actually change the course of the disease? We didn’t know until the first human study on soy food intake and breast cancer survival was published in 2009 in the Journal of the American Medical Association, suggesting that “[a]mong women with breast cancer, soy food consumption was significantly associated with decreased risk of death and [breast cancer] recurrence.” That study was followed by another study, and then another, each with similar findings. That was enough for the American Cancer Society, which brought together a wide range of cancer experts to offer nutrition guidelines for cancer survivors, concluding that, if anything, soy foods should be beneficial. Since then, two additional studies have been published for a total of five—five out of five studies that tracked more than 10,000 breast cancer patients—and they all point in the same direction.

Pooling all of the results, soy food intake after breast cancer diagnosis was associated with both reduced mortality and reduced recurrence—that is, a longer lifespan and less likelihood that the cancer comes back. This improved survival was for women with estrogen receptor negative tumors and estrogen receptor positive tumors, and for both younger women and for older women.

Pass the edamame.


Flaxseeds are protective for likely the same reasons. For more on this, see my videos Flaxseeds and Breast Cancer Survival: Epidemiological Evidence and Flaxseeds and Breast Cancer Survival: Clinical Evidence.

What about women who carry breast cancer genes? I touched on that in BRCA Breast Cancer Genes and Soy and Should Women at High Risk for Breast Cancer Avoid Soy?.

What about genetically modified soy? See GMO Soy and Breast Cancer.

Who Shouldn’t Eat Soy? An excellent question I answer in that video.

For even more information on soy, see:

Not all phytoestrogens may be protective, though. See The Most Potent Phytoestrogen Is in Beer and What Are the Effects of the Hops Phytoestrogen in Beer?.

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations: