Carbohydrate quality indices and lung cancer risk: a case-control study from Iran.

Considering that carbohydrates play an important role in supplying the body with energy and exhibit diverse mechanisms that can either prevent or stimulate cancer, we hypothesize that the quality of carbohydrate intake may be associated with cancer risk, including lung cancer. This hospital-based case-control study was conducted on 135 newly diagnosed lung cancer patients, and 237 healthy age- and sex-matched hospitalized controls. We used a valid and reliable 148-item Food Frequency Questionnaire to collect the dietary intake of subjects. Multivariate logistic regression was used to estimate the association between carbohydrate quality indices and the odds of lung cancer. After adjustment for confounding variables, the high glycemic index appears to be an increased risk factor for lung cancer [odds ratio (OR) = 2.51, 95% confidence interval (CI): 1.28-4.91]. No statistically significant association was found between glycemic load and lung cancer (OR = 2.51, 95% CI: 0.98-6.43). In contrast, the carbohydrate quality index (OR = 0.23, 95% CI: 0.11-0.48) and low-carbohydrate diet score (OR = 0.17, 95% CI: 0.08-0.36), were associated with a decrease in the risk of lung cancer. In summary, our study showed that a high glycemic index is a risk factor for lung cancer, however carbohydrate quality index and low-carbohydrate diet score is a dietary approach to reduce the risk of lung cancer.