Uncontrolled before-after studies

A low fermentable oligo-, di-, monosaccharides, and polyols (FODMAP) diet improved endometriosis-related symptoms by 50% or more in over 70% of the participants.
A low-nickel diet improved gastrointestinal symptoms and the intensity of dysmenorrhea (menstrual pain), dyspareunia (painful intercourse), and pelvic pain. Over 90% of the participants tested positive for nickel sensitivity.
A Mediterranean diet led to improvements in general pain, dysmenorrhea, dyspareunia, and constipation.

Controlled studies

A high antioxidant diet delivering 1,050 μg of vitamin A (retinol equivalents), 500 mg of vitamin C, and 20 mg of vitamin E reduced markers of oxidative stress, but clinical outcomes for endometriosis symptoms were not analyzed.
A diet that was 1) high in fiber (up to a 30% increase) and omega−3 fatty acids and 2) lower in amounts of dairy products (by at least 30%), meat (by at least 50%), gluten-containing foods, caffeine, alcohol, chocolate, saturated fat, and butter together with supplemental alpha-linolenic acid, linoleic acid, quercetin, nicotinamide, 5-methyltetrahydrofolate calcium salt (an alternative form of folic acid), titrated turmeric, and titrated parthenium (an herb used for menstrual pain) led to a reduction in pain symptoms and serum levels of PGE2 (an inflammatory prostaglandin), estradiol, and CA-125 (a marker that typically indicates ovarian cancer but is also associated with endometriosis).
Vitamin D (50,000 IU/week for 12 weeks) did not improve symptoms in women with severe endometriosis.
A combination of the vitamins B₆, A, C, and E and the minerals calcium, magnesium, selenium, zinc, and iron, along with lactic ferments and fish oil, taken for 6 months after endometrial ablation resulted in improvements in nonmenstrual pelvic pain.

Qualitative studies -Dietary counseling that increased participants’ consumption of fruits, vegetables, and fish and decreased their consumption of gluten, dairy, and carbohydrates increased the participants’ subjective sense of well-being and led to a deeper understanding of how they could improve their health by listening to their body’s reactions.

Animal studies

Elocalcitol (a vitamin D analog that suppresses cell proliferation) inhibited the development of endometrial lesions.
Omega−3 fatty acids reduced endometriosis implants.
Supplemental fish oil reduced postsurgical endometrial adhesions.
Epigallocatechin gallate (a catechin abundantly found in green tea) inhibited the development of experimental endometriosis.
Resveratrol inhibited the development and reduced the invasiveness of endometriosis.
Xanthohumol (a compound derived from hops) inhibited the development of endometriotic lesions.
The combination of N-acetyl cysteine, alpha-lipoic acid, and bromelain reduced the number of endometriotic lesions.
Quercetin inhibited endometriosis proliferation and induced cycle arrest and cell apoptosis.
A diet high in fat increased the number of endometriotic lesions.
Caloric restriction led to a reduced lesion weight.

Dietary interventions for the treatment of endometriosis Original paper