There are people who are not overweight but still have protruding belly or waist. Known as abdominal obesity, the condition affects up to three out of 10 people within the normal weight range, according to a study.
A research team led by Kim Mee-kyoung, an endocrinology professor at Yeouido St. Mary's Hospital in Seoul, analyzed the data of 12,217 people over 20 who took part in the National Health and Nutrition Examination Survey between 2009 and 2010. They found that 32 percent of people with a normal body mass index nonetheless had certain types of obesity.
The study was published online in the international journal Clinical Endocrinology.
The body mass 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.
But the BMI does not measure fat and muscle mass. So, regardless of height, if the waist measurement is 90 cm or more for men and 85 cm or more for women, the person is likely to have abdominal obesity.
Kim said, "People whose absolute weight falls into the normal category may not take exercise and a healthy diet seriously. This puts them at the risk of various illnesses. The way to reduce abdominal obesity is to follow a low-calorie diet regime and consistently do aerobic exercise such as walking."