La alimentación y la endometriosis, un área de investigación en desarrollo Translated title: Diet and endometriosis, an area of research in development

The etiology of endometriosis is poorly understood, and few modifiable risk factors have been identified. Dairy foods and some nutrients can modulate inflammatory and immune factors, which are altered in women with endometriosis. We investigated whether intake of dairy foods, nutrients concentrated in dairy foods, and predicted plasma 25-hydroxyvitamin D (25(OH)D) levels were associated with incident laparoscopically confirmed endometriosis among 70,556 US women in Nurses' Health Study II. Diet was assessed via food frequency questionnaire. A score for predicted 25(OH)D level was calculated for each participant. During 737,712 person-years of follow-up over a 14-year period (1991-2005), 1,385 cases of incident laparoscopically confirmed endometriosis were reported. Intakes of total and low-fat dairy foods were associated with a lower risk of endometriosis. Women consuming more than 3 servings of total dairy foods per day were 18% less likely to be diagnosed with endometriosis than those reporting 2 servings per day (rate ratio = 0.82, 95% confidence interval: 0.71, 0.95; P(trend) = 0.03). In addition, predicted plasma 25(OH)D level was inversely associated with endometriosis. Women in the highest quintile of predicted vitamin D level had a 24% lower risk of endometriosis than women in the lowest quintile (rate ratio = 0.76, 95% confidence interval: 0.60, 0.97; P(trend) = 0.004). Our findings suggest that greater predicted plasma 25(OH)D levels and higher intake of dairy foods are associated with a decreased risk of endometriosis.

Background Only two case-control studies have examined the associations between consumption of meat products and endometriosis risk with inconsistent results. Consumption of animal products has the potential to influence endometriosis risk through effects on steroid hormones levels. Objectives To determine whether higher intake of red meat, poultry, fish, and seafood are associated with risk of laparoscopically-confirmed endometriosis Study Design 81,908 participants of the prospective Nurses’ Health Study II were followed from 1991–2013. Diet was assessed via food frequency questionnaire every 4 years. Cox proportional hazards models were used to calculate rate ratios (RR) and 95% confidence intervals (CIs). Results During 1,019,294 person-years of follow-up, 3,800 cases of incident laparoscopically-confirmed endometriosis were reported. Women consuming >2 servings/day of red meat/day had a 56% higher risk in endometriosis (95% CI=1.22–1.99; P trend <0.0001) compared to those consuming ≤1 serving/week. This association was strongest for non-processed red meats (RR=1.57; 95% CI= 1.35–1.83 for ≥2 servings/day versus ≤1 servings/week; P trend <0.0001), particularly among women had not reported infertility (p interaction =0.0004). Women in the highest category of processed red meat intake also had a higher risk of endometriosis (RR=1.20; 95% CI=1.06–1.37 for ≥5 servings/week versus <1 serving/month; P trend =0.02). Intakes of poultry, fish, shellfish, and eggs were unrelated to endometriosis risk. Conclusions Our prospective analysis among premenopausal US nurses suggests that red meat consumption may be an important modifiable risk factor for endometriosis, particularly among women with endometriosis who had not reported infertility and thus were more likely to present with pain symptoms. Well-designed dietary intervention studies among women with endometriosis could help confirm this observation.

Endometriosis is a hormone-related, chronic inflammation in women of childbearing age. The aetiology and pathogenesis of endometriosis are not yet fully understood. For other illnesses classed as lifestyle diseases, the link between nutrition and pathogenesis has already been researched and proven. With regard to these findings, the question continues to arise as to whether and how a specific diet and lifestyle could also influence pathogenesis and the progression of endometriosis. The aim of this review is to examine the data and determine what influence nutrition has on the development of endometriosis or on existing disease. The study results currently available do not permit a clear, scientific recommendation or indicate a detailed diet. In summary, it can be said that fish oil capsules in combination with vitamin B 12 have been associated with a positive effect on endometriosis symptoms (particularly of dysmenorrhoea). Alcohol and increased consumption of red meat and trans fats are associated with a negative effect. The results of the studies listed with regard to fruit and vegetables, dairy products, unsaturated fats, fibre, soy products and coffee are not clear. Therefore, the general recommendations for a balanced and varied diet in line with the guidelines of the Deutsche Gesellschaft für Ernährung e. V. [German Nutrition Society] apply, along with the recommendation to cut out alcohol. In order to be able to derive more concrete recommendations, we require further studies to investigate the influence of nutrition on endometriosis.