Livia S. A. Augustin

Diabetes Risk Reduction Diet and Endometrial Cancer Risk

Diabetes increases endometrial cancer risk. We investigated the role of a diabetes risk reduction diet (DRRD) on the risk of endometrial cancer using data from a multicentric, Italian hospital-based case–control study (1992–2006) enrolling 454 histologically confirmed cases of endometrial cancer and 908 controls matched by age and center. We derived a DRRD score assigning higher scores for higher intakes of cereal fiber, fruit, coffee, polyunsaturated:saturated fatty acid ratio, and nuts and for lower glycemic load and lower intakes of red/processed meat and sugar-sweetened beverages/fruit juices. The odds ratios (OR) of endometrial cancer according to the DRRD score were derived by multiple conditional logistic regression models. The OR for high (DRRD score >24, i.e., third tertile) versus medium–low adherence to the DRRD was 0.73 (95% confidence interval, CI, 0.55–0.97). Similar results were observed after the exclusion of diabetic women (OR 0.75; 95% CI, 0.56–1.00) and allowance for total vegetable consumption (OR 0.80; 95% CI, 0.60–1.07). Inverse associations were observed in most of the analyzed subgroups. The OR for high DRRD combined with high vegetable consumption was 0.45 (95% CI, 0.28–0.73). Our results suggest that diets able to reduce diabetes risk may also reduce endometrial cancer risk. High vegetable consumption combined with high adherence to the DRRD may provide additional benefit in endometrial cancer prevention.

Plant-Based Diets and Ovarian Cancer Risk

Objective: To assess the relationship between adherence to various plant-based diets, as measured by overall, healthy, and unhealthy plant-based diet indices (PDI, hPDI, uPDI), and ovarian cancer risk. Methods: We obtained data on 1031 cases of ovarian cancer and 2411 controls from a case-control study conducted in Italy. PDI, hPDI, and uPDI were calculated using data from a validated food frequency questionnaire. We used logistic regression to calculate the odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) of ovarian cancer for PDI, hPDI, and uPDI, adjusting for several possible confounders. Results: PDI and hPDI were inversely related to ovarian cancer risk (OR = 0.70 for the fourth compared to the first quartile, 95% CI: 0.55–0.89, and OR = 0.67, 95% CI: 0.53–0.84, respectively). On the other hand, a higher uPDI was related to a higher risk of ovarian cancer (OR = 1.78, 95% CI: 1.40–2.28). The estimates for a 5-point increment in the indices were 0.88 (95% CI: 0.81–0.95) for PDI, 0.90 (95% CI: 0.83–0.96) for hPDI, and 1.15 (95% CI: 1.07–1.23) for uPDI. Consistent associations for the three indices were observed across strata of age, family history of breast/ovarian cancer, educational level, parity, oral contraceptives use, and menopausal status. Conclusions: Plant-based diets favorably influence ovarian cancer risk; plant-based diets characterized by a high intake of unhealthy plant foods are linked to an increased risk. Promoting diets rich in healthy plant foods could support the reduction of ovarian cancer risk.