Previous research suggests that adult men consume larger amounts of calories while eating-out than when eating meals prepared at home. Therefore, this study aimed to investigate the association between the daily eating-out rate and body mass index (BMI) in the Korean population. The study used data from 18,019 individuals aged ≥19 years who participated in the Korea National Health and Nutrition Examination Survey (KNHANES) from 2013 to 2016. BMI was measured according to the Asia-Pacific BMI measurement criteria. A multinomial logistic regression analysis was used to examine the validity of the association between the eating-out rate and BMI. In this population, women with higher eating-out rates were found to have higher BMIs. Specifically, the risks of becoming obese or overweight increased among those with a 1%-50% (obesity odds ratio (OR) = 1.28, 95% confidence interval [CI]: 1.09-1.51; overweight OR = 1.38, 95% CI: 1.14-1.64) or 51%-100% daily eating-out rate (obesity OR = 1.51, 95% CI: 1.24-1.84; overweight OR = 1.50, 95% CI: 1.20-1.87), relative to those who reported never eating-out. By contrast, no statistically significant association between the daily eating-out rate and BMI was observed among men. Notably, we observed positive associations of the daily eating-out rate with obesity and being overweight in South Korean women, but not men. Our findings suggest that education about proper habits when eating-out is needed to prevent obesity.
Keywords: BMI; Korea National Health and Nutrition Examination Survey; eating-out rate; obesity; overweight.