Glycemic load, glycemic index, and carbohydrate intake in relation to pancreatic cancer risk in a large US cohort

Background Consumption of diets with high glycemic load has been hypothesized to increase pancreatic cancer risk by raising postprandial glucose levels and insulin secretion. Methods The authors analyzed data from the American Cancer Society Cancer Prevention Study II (CPS-II) Nutrition Cohort to examine the association between pancreatic cancer and glycemic load, glycemic index (GI), and intake of carbohydrates. Diet was assessed among 124,907 men and women who were cancer-free and non-diabetic at baseline in 1992 using a validated 68-item food frequency questionnaire (FFQ). During 9 years of follow-up, 401 incident pancreatic cancer cases were identified. Cox proportional hazards modeling was used to compute hazard rate ratios (RR) adjusted for potential confounding factors. Results We found no association between glycemic load, GI, or carbohydrate intake and risk of pancreatic cancer in this population. The hazard rate ratio (RR) was 1.01 (95% CI 0.75-1.37, trend P = 0.80) for glycemic load, 0.92 (95% CI 0.68-1.24) for GI, and 1.10 (95% CI 0.80-1.51) for carbohydrate intake among men and women in the highest quintile compared to the lowest quintile of each measure. We also found no significant association between these measures and pancreatic cancer risk among individuals who show a greater susceptibility towards insulin insensitivity, such as those who are overweight or more sedentary. Conclusion Overall, our data do not support the hypothesis that glycemic load or index, or carbohydrate intake are associated with a substantial increase in pancreatic cancer risk; however, a weak positive association cannot be ruled out.