The interplay of sleep duration, working hours, and obesity in Korean male workers: The 2010–2015 Korea National Health and Nutrition Examination Survey

Abstract

The purpose of this study was to clarify the odds ratio for association between working hours and obesity in Korean male wage workers and investigate the role of sleep duration. This study is a cross-sectional one using large-scale national data from the Korea National Health and Nutrition Examination Survey collected between 2010 and 2015 to evaluate 2,592 male wage workers (between the ages of 19 and 60 years). Obesity was defined as 25kg/m2 or more and working hours per week were categorized into <40, 40–49, 50–59, and ≥60 hours. Multiple regression analysis was performed to examine the odds ratio for association between working hours and obesity, after controlling for age, education, income, marital status, smoking, drinking, physical activity, daily energy intake, sleep duration, hypertension, diabetes, dyslipidemia, work schedule, and job category. Next, to study the mediating effect of sleep duration on the association between working hours and obesity, an analysis was performed using the Baron and Kenny method and the Sobel test. Results showed that workers with 50 to 59 hours had 1.4 times higher odds (odds ratio [OR] = 1.4, confidence interval [CI]: 1.11–1.85) of obesity and workers with 60 hours or more had 1.4 times higher odds (OR = 1.4, CI: 1.06–1.90) of obesity than workers with less than 40 hours. Sleep was found to have a mediating effect on the association between working time and body mass index. Therefore, the results of this analysis suggest that practitioners should identify potential factors such as working time and sleeping time when preventing work-related obesity.

The relationship between working hours and lifestyle behaviors: Evidence from a population-based panel study in Korea

“…29 A large portion of the literature has reported that long working hours are linked with lower quantity and quality of sleep. 11,12,[30][31][32] Hence, it is believed that insufficient recovery due to sleep deprivation is considered a critical component of the pathway from long working hours to health problems. 12,33 Another experimental study revealed that long working hours reduced sleep time and increased fatigue.…”

“…35 Second, workers with long working hours have less time to engage in healthy lifestyle habits, such as physical exercise and sufficient sleep. 30 Time constraints may leave some workers with few choices but to rely only on alcohol and smoking as coping strategies to relieve stress. Researchers have reported that a reduction in working time promotes regular exercise, decreases the likelihood of smoking, 36 and leads to beneficial effects on sleep quality and duration.…”

A Study of Lifestyle Habits of Remote Workers - Comparison of Tele-Exercise and Face-to-Face Exercise

“…Furthermore, insufficient sleep was found to have a mediating effect on the connection between working hours and obesity. Consequently, these findings suggest the importance of identifying factors such as working and sleeping hours for the prevention and management of obesity in wage workers [22].…”

The impact of working hours on pregnancy intention in childbearing-age women in Korea, the country with the world’s lowest fertility rate

“…In fact, Korea had the second highest number of working hours among OECD countries in 2022. The effects of these long working hours are considered an important factor in negative health outcomes, such as musculoskeletal symptoms, poor mental health, and decreased kidney function [17][18][19][20][21].…”