Impact of Social Jetlag on Weight Change in Adults: Korean National Health and Nutrition Examination Survey 2016-2017.

Social jetlag, the circadian misalignment reflecting the discrepancy between the circadian clock and social clock, has been implicated in weight-related issues. The objective of the present study was to determine whether there was an association between social jetlag and body weight change among adults in a large, nationally representative general population. This study was based on data from the Korean National Health and Nutrition Examination Survey, conducted during 2016-2017 by the Korean Ministry of Health and Welfare. Of the 16,277 participants, data from 8295 adults were included in the analysis. Men with social jetlag > 2 h had a significantly higher risk of weight gain (odd ratios (OR): 1.787; 95% confident interval (CI): 1.192-2.679) than those with social jetlag < 1 h, after adjustment for age, sociodemographic factors, lifestyle behaviors, chronic disease, obesity and average sleep duration. Women with weight gain had a higher social jetlag (>2 h), and women with social jetlag > 2 h had a higher proportion of weight gain. However, we did not find a significant association of social jetlag with weight gain after adjusting for confounding factors in women. There was no significant association between social jetlag and weight loss in men and women. Higher social jetlag was independently associated with an increased risk of weight gain in men. We propose that social jetlag may contribute to the obesogenic tendency in men, and that there is a potential for body weight to be managed with a circadian approach.