About two in 10 women aged 19-24 are underweight, according to a recent study by the Korea Institute for Health and Social Affairs.
The institute analyzed the body mass index of people in different age groups.
The index is calculated as weight divided by height squared. An index below 18.5 is regarded as underweight, 18.5 to 24.9 as normal weight, 25 to 29.9 as overweight, and 30 or more obese.
Among women between 19 and 24, 17.5 percent had an index below 18.5, compared to 8.5 percent among women aged 25 to 44 and 2 percent among those aged 45 to 64.
Overall, 6.9 percent of women and 3.5 percent of men had body mass indices below 18.5.
Some 60 percent of 19 to 24-year-old women said they skipped breakfast regularly, while that figure was 30.4 percent among women aged 25 to 44, 16.9 percent among those aged 45 to 64 and 7.3 percent among those aged 64 or over.
Researchers said dieting probably accounted for the high number of underweight young women.