1755P Carbohydrate Quality Index and Incidence of Obesity-Related Cancers: the Seguimiento Universidad De Navarra (SUN) Project

Obesity is a strong risk factor for cancer, with more than 40,000 diagnosed cancers every year attributed to obesity. The role of nutrition in obesity-related cancers (ORC) needs to be better understood to develop tailored prevention strategies. The quality, rather than the quantity, of carbohydrate intake, seems to play a significant role. We investigated the relationship between dietary carbohydrate quality and risk of developing ORC in the "Seguimiento Universidad de Navarra” (SUN) Mediterranean cohort. A total of 18,446 Spanish university graduates [mean age 38 years (SD 12), 61% women, mean BMI 23.5 kg/m2 (SD 3.5 kg/m2)], with no personal history of cancer, were followed-up for a median of 13.7 years. Baseline carbohydrate quality index (CQI) was assessed using 4 previously defined criteria: high dietary fibre intake, low glycemic index, high whole-grain: total-grain ratio and high solid carbohydrate: total carbohydrate ratio. Subjects were classified into tertiles according to their CQI score. Obesity-related incident cases were confirmed by an oncologist using medical records and by querying the National Death Index blindly to dietary exposures. During follow-up, 269 incident cases of obesity-related cancer were confirmed. A higher quality of carbohydrate intake, as measured by the baseline CQI, was associated with a lower risk of ORC with multivariable-adjusted hazard ratio (HR) for the upper (T3) versus the lowest tertile (T1) of 0.68 (95% confidence interval: 0.48, 0.97). Particularly, a higher dietary fibre intake was inversely associated with ORC, HR T3 vs. T1 = 0.58 (0.38, 0.89). In this Mediterranean cohort, we observed a significant inverse association between a better global quality of carbohydrate intake and the risk of obesity-related cancers. This finding suggests that strategies for cancer prevention should emphasize the quality of carbohydrate intake, and particularly the dietary fibre intake.