A Prospective Cohort Study of Vitamins B, C, E, and Multivitamin Intake and Endometriosis

Abstract

Purpose Diet is a potentially modifiable risk factor for endometriosis. It has been hypothesized that vitamins C, E, and the B vitamins may influence factors involved in the pathogenesis of endometriosis, such as oxidative stress and steroid hormone metabolism. In this large, prospective cohort study, we examined the relation between intake of vitamins C, E, the B vitamins, and the use of multivitamin supplements and diagnosis of endometriosis. Methods Data were collected from women in the Nurses’ Health Study II between 1991 and 2005. Diet was assessed via food frequency questionnaire. Incidence rate ratios (RR) and 95% confidence intervals (CI) were estimated using time-varying Cox proportional hazards models. Results A total of 1383 incident cases of laparoscopically-confirmed endometriosis were observed among 70,617 women during 735,286 person years of follow-up. Intakes of thiamine (B1) (RR = 0.84, CI = 0.72–0.99; P-value, test for linear trend [P] = 0.04), folate (B9) (RR = 0.79, CI = 0.66–0.93; P = 0.003), vitamin C (RR = 0.81, CI = 0.68–0.95; P = 0.02), and vitamin E (RR = 0.70, CI = 0.59–0.83; P<0.0001) solely from food sources were inversely related to endometriosis diagnosis. However, intakes of these nutrients from supplements alone were unrelated to endometriosis. Conclusion Thiamine, folate, vitamin C, and vitamin E from food sources are inversely related to endometriosis risk. Our results suggest that the protective mechanism may not be related to the nutrients themselves but rather other components of foods rich in these micronutrients or factors correlated with diets high in these vitamin-rich foods.

Influence of diet on the risk of developing endometriosis

“…However, supplying these vitamins via dietary supplement had no influence on the occurrence of endometriosis [10]. This may suggest that other factors present in food may modify the risk of endometriosis [10]. A similar study was conducted in 2008 by Mier-Cabrera et al on a group of women suffering from endometriosis (n = 83) compared to a control group of healthy women (n = 80).…”

“…It has been found that consumption of products rich in vitamins such as folic acid (p = 0.003), vitamin C (p = 0.02), and vitamin E (p < 0.0001) is inversely proportional to the risk of developing endometrio- sis. However, supplying these vitamins via dietary supplement had no influence on the occurrence of endometriosis [10]. This may suggest that other factors present in food may modify the risk of endometriosis [10].…”

“…Consumption of these vitamins and antioxidants decreases the risk of developing endometriosis, potentially by influencing oxidative stress and steroid hormone metabolism in the body. From 1991 to 2005 a cohort study was conducted on a group of 70,617 women by Darling et al (2013). The experimental group (n = 1.383) consisted of women with the endometriosis confirmed by laparoscopy and the control group (n = 69.234) consisted of the healthy women.…”

“…As such, diet and lifestyle can also impact the risk of developing endometriosis [10,11]. There are a number of plausible theories linking endometriosis to dysmenorrhea, defined as painful menstrual cramps coming from the uterus in a normal pelvis.…”

Research Priorities for Endometriosis: Recommendations From a Global Consortium of Investigators in Endometriosis

“…There were a rich range of methods and expertise: animal models, small human trials, and cohort studies. [17][18][19][20][21][22][23] Among the 3 animal studies, the one using a Wistar albino rat model observed that dose-dependent vitamin C supplementation significantly reduced the volumes and weights of the endometriotic cysts. 18 In a chimeric mouse model, dietary fish oil supplementation inhibited formation of endometriosisassociated adhesions, 21 whereas in a BALB/c mouse model, xanthohumol was observed to inhibit the development of endometriotic lesions without evidence of a negative impact on the uterine horn or ovaries.…”