The association of dietary glycemic index and glycemic load with the risk of insomnia in the adult population

Background A dietary pattern with a high glycemic index (GI) and glycemic load (GL) can be a precursor to sleep disorders that link to many chronic diseases. We aimed to assess the association of dietary GI and GL with the risk of insomnia in Iranian adults. Methods A total of 111 newly diagnosed insomnia cases and 333 controls aged 18-60 years were included in this case-control study. The participants' dietary intakes were collected using a valid and reliable food frequency questionnaire. The diagnosis of insomnia in subjects was performed by a neurologist using the Insomnia Severity Index (ISI) questionnaire. Multivariable logistic regression models, adjusted for the potential confounders, were used to determine the risk of insomnia according to tertiles of dietary glycemic indices. Results The mean (SD) age and BMI of the study population (78.6% female) were 31.8 (10.0) years and 24.70 (3.62) kg/m(2), respectively. The median (IQR) of dietary GI and GL in subjects was 62.7 (57.0-68.6) and 213.5(167.4-268.5), respectively. Based on the multivariable-adjusted model, after controlling for age, sex, physical activity, obesity, smoking, socioeconomic score, general health questionnaire (GHQ) score, and dietary energy intake, the odds of insomnia were increased across tertiles of dietary GL[(OR:2.72,95%CI:1.10-6.70),(P-trend = 0.017)], however, no significant association was observed between high GI diet and insomnia risk [(OR:1.38,95%CI:0.77-2.47),(P-trend = 0.298)]. Conclusions Our results revealed that greater adherence to dietary pattern with high GL could be increased the odds of insomnia in Iranian adults.