Nutritional determinants of epithelial ovarian cancer risk: A case-control study in Mexico

Background. Variations in the incidence of cancer can be influenced by diet and specific lifestyles. In the last years, diet has been evaluated as an important factor in the development of ovarian cancer, even though the results have not been consistent. Dietary factors related to the risk of ovarian cancer in Mexican women were evaluated. Methods: A case-control study in Mexico City was done during 1995-1997 in a social security hospital, evaluating 84 new cases of ovarian cancer and 629 controls. A validated questionnaire with 116 items about the frequency and type of food intake was used. The analysis of nutrients was done with the residual method adjusted for total energy intake and other predictor variables through logistic regression methods. Also, partition models estimated the total caloric intake for other sources. Results: The nutrients negatively associated with ovarian cancer in the highest versus the lowest tertile were retinol (OR 0.52; p for trend = 0.03) and vitamin D (OR 0.43; 95% Cl 0.23-0.80; p = 0.01; residual model). Additionally, carbohydrates were positively associated (partition model: OR 1.08; 95% Cl 1.00-1.15), and tortilla intake did not show an association with ovarian cancer (OR 0.96; 95% Cl 0.78-1.17). Conclusions: The diet of the Mexican population is rich in carbohydrates; in Mexico corn intake is the main energy source. On the other hand, vitamins such as retinol and vitamin D were shown to be associated with this neoplasm in a protective way; nevertheless, further studies are necessary to allow us to corroborate our results. This is the first attempt in our country that relates the Mexican diet to ovarian cancer.