Trends in obesity, leisure-time physical activity, and sedentary behavior in Korean adults: Korea national health and nutritional examinations survey from 2014 to 2021

by Yunmin Han, Hoyong Sung, Younghwan Choi, Yeon Soo Kim

This study aimed to investigate trends in obesity by dividing it based on body mass index (BMI) and waist circumference indicators, sedentary behavior, and leisure-time physical activity (LTPA) in Korean adults from 2014 to 2021. This study also aimed to determine the adherence rate of people with obesity to physical activity.

Data from the Korea National Health and Nutritional Examination Survey (KNHANES) from 2014 to 2021 were used. A total of 42,676 participants 19 years or older were included in the final analysis. Sociodemographic characteristics, anthropometric measurements, and physical activity levels were recorded. Physical activity levels were assessed using the Global Physical Activity Questionnaire, a self-reported questionnaire. Multivariable logistic regression analysis adjusted for covariates was used to investigate the prevalence of obesity and sitting time or adherence to meeting the physical activity guidelines for each survey year.

This study included 42,676 adults. The weighted prevalence of obesity in all ages significantly increased from 30.8% (29.1%-32.5%) in 2014 to 34.5% (32.9%-36.2%) in 2017 and 37.3% (35.5%-39.1%) in 2021 (p for trend < 0.004). The weighted adherence rate to LTPA ranged from 25.5% (95% confidence interval [CI], 23.7%-27.2%) in 2014 to 20.5% (95% CI, 18.7%-22.2%) in 2021(p for trend < 0.001). The weighted prevalence of sitting time for 8 h/day or more significantly increased from 46.7% (44.4%-49.0%) in 2014 to 56.2% (54.4%-58.0%) in 2017 and 63% (60.7%-65.3%) in 2021 (p for trend < 0.001). According to this study, the LTPA level among women with obesity was significantly low.

From 2014 to 2021, obesity and sedentary behavior significantly increased and adherence to LTPA decreased among Korean adults. Given these concerning trends, comprehensive interventions are needed at the national level to encourage healthy lifestyle behaviors.