Findings from a systematic review of clinical trials support a beneficial effect for vitamins D, C and E against symptoms associated with endometriosis, a common disease of reproductive-aged women that causes chronic pelvic pain, painful menstrual periods, infertility, pain during sex and reduced quality of life. The condition is characterized by the presence of endometrial-like tissue growing outside of the endometrium, which lines the uterus. Authors Sophia Tsokkou and colleagues concluded that consuming the vitamins "represents a safe, low-cost adjunct therapy that can effectively mitigate endometriosis-related oxidative stress and pelvic pain."

High-dose vitamin D was associated with a reduction in pelvic pain, lower high-sensitivity C-reactive protein (hs-CRP, a marker of inflammation) and greater total antioxidant capacity. The combination of antioxidant vitamins C and E significantly lowered markers of oxidative stress, decreased daily pelvic pain and reduced menstrual pain.

The systematic review included seven randomized, controlled trials that included a total of 343 women with endometriosis. Vitamin D doses used in the trials included 50,000 IU once per week, 50,000 IU every two weeks or 2,000 IU daily. Vitamin C doses ranged from 343 mg to 1000 mg and vitamin E doses ranged from 38 to 804 mg per day.

"By targeting inflammatory and oxidative pathways that are central to endometriosis pathogenesis, these vitamins offer a mechanistically coherent, low-toxicity strategy to complement standard hormonal or surgical treatments," Tsokkou and her associates wrote. The findings were reported in the February 1, 2026, issue of the International Journal of Molecular Science.¹