Eating a plant-based diet, along with other nutrition interventions including avoiding meat and consuming seaweed, may help prevent and treat endometriosis, according to a new scientific review published in the medical journal Frontiers in Nutrition.
Endometriosis, which affects roughly 190 million women and girls of reproductive age globally, is characterized by the presence of endometrial tissues outside the uterine lining, typically on the external surface of the uterus, the ovaries, fallopian tubes, abdominal wall, or intestines. Common symptoms include severe pelvic pain, menstrual cramps, genital pain during or after sex, fertility complications, fatigue, low back pain, bloating, constipation, and diarrhea.
While current treatments include over-the-counter non-steroidal anti-inflammatory drugs and hormonal treatments, a cross-sectional study estimates that 60 percent of patients have chronic pain regardless of medical treatment, along with adverse effects on their quality of life.
This new review, undertaken by researchers from the Physicians Committee for Responsible Medicine (PCRM), aimed to better understand the role of nutrition in the prevention and treatment of endometriosis.
Eating meat makes endometriosis worse
The review notes that higher levels of estrogen circulating in the body can worsen the pain and inflammation associated with endometriosis. Consuming red and processed meat, which may be associated with increased estrogen levels, has been shown to increase the risk of endometriosis, according to several studies.
The Nurses’ Health Study II showed that women consuming more than two servings of red meat per day had a 56 percent greater risk of endometriosis, compared with those consuming less than one serving of red meat per week.
Increased consumption of chicken was also associated with higher risk of endometriosis. Another study found that a higher intake of beef, other red meat, and ham was associated with an increased risk of developing endometriosis.
Plant foods help reduce estrogen levels
Conversely, the review found that reducing dietary fat and increasing dietary fiber, which is found only in plant foods, has been shown to reduce estrogen levels by up to 25 percent. Plant-based diets are typically lower in fat and higher in fiber than diets that include animal products. In a clinical trial of women with menstrual pain, a low-fat vegan diet was associated with increased plasma concentrations of sex-hormone binding globulin, which in turn would be expected to reduce estrogen activity.
“Eating meat and fatty foods may lead to excess estrogen in the body, which can cause endometriosis pain to flare, while fiber—found only in fruits, vegetables, grains, and beans—may help reduce pain by flushing excess estrogen out of the body,” Hana Kahleova, MD, PhD, director of clinical research at the PCRM, said in a statement.
Research shows that vitamin C, which is found in citrus as well as other fruits and vegetables, and vitamin E, which is found in nuts and seeds and certain fruits and vegetables, may also reduce endometriosis symptoms.
Seaweed may also be beneficial. A study in healthy postmenopausal women found seaweed consumption lowered estrogen levels. A case study of premenopausal women found that intake of bladderwrack, an edible brown kelp, reduced estrogen levels. While these studies suggest the potential benefits of seaweed consumption on estrogen concentrations, the effects on endometriosis await further research.
The authors say it is not yet known how universal the benefits of a healthy plant-based diet will be for women with endometriosis, and further studies are in progress.
Vegan diet helps relieve menstrual cramps
Previous research has noted benefits of a plant-based diet on women’s menstrual cycle. An analysis of studies that was presented at the North American Menopause Society (NAMS) annual meeting last year suggested that diet may be a key contributor to menstrual pain (also called dysmenorrhea).
This research showed that while diets high in inflammatory foods such as meat, oil, sugar, salt, and coffee can make the pain worse, eating vegan has been shown to tame the pain by reducing the inflammation that contributes to it.
Previous research has also found benefits such as its ability to reduce menopause hot flashes. A study published in the journal Menopause by the North American Menopause Society found that a plant-based diet rich in whole soybeans reduces moderate-to-severe hot flashes by 84 percent.
And, notably, at the end of the study, nearly 60 percent of participants following a plant-based diet reported becoming totally free of moderate and severe hot flashes, while the group that did not have a diet change did not report a change in this variable. Many study participants also reported improvements in sexual symptoms, mood, and overall energy.
“This is a game changer for women aged 45 and over, most of whom we now know can get prompt relief from the most severe and troubling menopause symptoms without drugs,” Neal Barnard, MD, president of the PCRM and study lead researcher, said at the time.