A national health survey found that 35.4% of Korean adults were classified as obese in 2025, up 7.5 percentage points from 27.9% in 2016. The rate exceeded half among men in their 30s at 52.1% and men in their 40s at 53.1%, with obesity defined as a body mass index of at least 25.0.
Ulsan and South Jeolla recorded the highest provincial rates, while areas with higher obesity rates also tended to have lower household incomes and lower walking and strength-training participation. The findings point to differences in health behavior and local socioeconomic conditions rather than a single national pattern.