International students are experiencing health problems due to many lifestyle changes, such as those in dietary and sleep patterns. We conducted this study to identify the associations among sleep patterns, changes in eating habits after studying abroad, and overweight or obesity in international students. In this cross-sectional study, we analyzed data on health-related variables, changes in eating habits after studying abroad, and sleep patterns that were collected from 225 international students in South Korea. Approximately half of the participants experienced poor sleep (47.6%). After adjusting for covariates such as age, gender, nationality, and acculturative stress, the subjects who had poor sleep quality were 2.020-fold (adjusted odds ratio, 95% confidence interval = 1.045–3.906) more likely to be overweight and obese than those who had good sleep quality. There were significant differences in changes of eating habits after studying abroad according to sleep quality (p < 0.001). When subjects were stratified into groups according to changes in eating habits after studying abroad, the risk of overweight and obesity increased in those with poor sleep quality but not in those with good sleep quality among subjects who had changes in bad eating habits. However, the risk of overweight and obesity did not differ among subjects with changes in good eating habits regardless of their sleep quality.

Daily sleep duration is known to be associated with obesity and dyslipidemia. This study was performed to examine the interactions between daily sleep duration and the risks of obesity and dyslipidemia according to dietary macronutrient consumption in 14,680 Korean adults using the 5th Korean National Health and Nutrition Examination Survey. Sleep duration was inversely associated with body mass index (P < 0.001), waist circumference (P < 0.001), total cholesterol (P < 0.001), and low-density lipoprotein -cholesterol (P = 0.001). Participants with short sleep durations consumed less dietary protein (P < 0.001) and fat (P < 0.001), and consumed more dietary carbohydrates (P < 0.001). Among participants with the shortest sleep duration (≤5 hours a day), the odds ratio of obesity was found to increase in the high fat consumption group (1.393, 95% confidence interval 1.083–1.790) and decrease in the high carbohydrate consumption group (0.770, 95% confidence interval 0.604–0.983). High fat and low carbohydrate consumption were confirmed to be associated with the risk of obesity in the shortest sleep duration group (≤5 hours a day). These findings indicate that sleep duration was negatively associated with obesity and dyslipidemia-related indices in Korean adults. Additionally, the association of short sleep duration with the risk of obesity was potentially changed by dietary fat and carbohydrate consumption.

We previously reported that women with short sleep duration consumed more dietary carbohydrate and showed an increased risk for obesity compared to those who slept adequately, but not for men. Using a cross-sectional study of 17,841 Korean women, we investigated the influence of sleep duration on obesity-related variables and consumption of dietary carbohydrate-rich foods in relation to menopausal status. Premenopausal women with short sleep duration had significantly greater body weight (p = 0.007), body mass index (p = 0.003), systolic and diastolic blood pressures (p = 0.028 and p = 0.024, respectively), prevalence of obesity (p < 0.016), and consumption of more carbohydrate-rich foods such as staple foods (p = 0.026) and simple sugar-rich foods (p = 0.044) than those with adequate sleep duration after adjustment for covariates. Premenopausal women with short sleep duration were more obese by 1.171 times compared to subjects adequate sleep duration (95% confidence interval = 1.030–1.330). However, obesity-related variables, dietary consumption, and odds of being obese did not differ according to sleep duration for postmenopausal women. The findings suggest that the increased risk for obesity and consumption of dietary carbohydrate-rich foods with short sleep duration appeared to disappear after menopause in Korean women.

Short sleep duration has been reported to be associated with various health problems. This study examined the influence of sleep duration on the odds of being obese in relation to the consumption of dietary antioxidant vitamins among 3941 Korean men between 40 and 69 years of age. After adjusting for age, education, household income, marital status, insomnia, smoking and drinking status, participants with short sleep duration (<6 h) had significantly higher body mass index (p = 0.005), body fat mass (p = 0.010), body fat percentage (p = 0.021), waist circumference (p = 0.029), as well as the odds ratio (OR) of risk of obesity [OR (95% CI) = 1.467 (1.282–1.678)], compared to participants with optimal sleep duration (≥7 h). Short sleepers with a low consumption of dietary antioxidant vitamins had a higher risk of obesity than those with a high consumption of dietary antioxidant vitamins; however, this relationship did not hold among those with optimal sleep duration. Although a causal relationship among sleep-related variables could not be definitively demonstrated because of this study’s cross-sectional design, our results suggested that the increased risk of obesity associated with short sleep duration may be modified by the consumption of dietary antioxidant vitamins.