Dietary insulin indices and low-carbohydrate diet and the odds of colorectal cancer: a case-control study

Abstract

Background Regarding the role of insulin and insulin-inducing dietary factors in some cancers’ etiology, we hypothesized that the risk of colorectal cancer may be lessened by following a lower carbohydrate and insulinogenic diet. Therefore, we performed this study to explore the association between a low-carbohydrate diet and insulin indices and the odds of colorectal cancer. Method This hospital-based case-control study was conducted on 150 newly diagnosed colorectal cancer patients and 300 healthy age- and sex-matched hospitalized controls. A valid and reliable food frequency questionnaire was used to calculate the insulin indices and low-carbohydrate diet score. Multivariate logistic regression was used to estimate the association between insulin indices and low-carbohydrate diet and the odds of colorectal cancer. Result After adjusting for potential confounders, individuals in the highest tertile of insulin indices had a higher risk of colorectal cancer (ORinsulin index = 3.46; 95% CI, 2.00–5.96; ORinsulin load = 2; 95% CI, 1.17–3.41). No association was found between a low-carbohydrate diet and colorectal cancer (OR = 1.55; 95% CI, 0.85–2.84). Conclusion Current results demonstrated that a high insulinemic diet was associated with a higher risk of colorectal cancer.