The prevalence of overweight, obesity, and metabolic disorders and their relationship with BMI were studied in South Korean adults. The appropriate BMI categories for overweight and obesity for Koreans were evaluated.
The 1998 Korea National Health and Nutrition Examination Survey was the first such survey, to our knowledge, conducted on a cross-sectional and nationally representative population. The survey provided data on body weight; height; fasting serum glucose; triacylglycerol; total, low-density lipoprotein, and high-density lipoprotein cholesterol; blood pressure; and various other questions that were incorporated into this study. A total of 39,060 persons over the age of 1 year from 12,283 households participated in the Health and Nutrition Interview Survey. Of these, 10,876 people over the age of 10 years old participated in the Health Examination. We analyzed data from 7962 adults over the age of 20 years old.
The overweight (BMI, >/=25.0 to <30.0) and obesity (BMI, >/=30) rates were low among Korean adults: 23.4% and 1.7% in men and 24.9% and 3.2% in women, respectively. However, the prevalences of diabetes, hypertension, and abnormal concentrations of serum triacylglycerol and total, low-density lipoprotein, and high-density lipoprotein cholesterol were high at 10.5%, 27.1%, 29.0%, 34.5%, 28.4%, and 37.4%, respectively. These disorders were age dependent, and, in general, there was a strong linear relationship between BMI and the disorders. The relative risk of disorders doubled at a BMI of 23.0 to 24.0 and tripled at a BMI of 26.0, compared with a baseline BMI of 18.5 to 22.0.
High rates of diabetes, hypertension, and dyslipidemia were noted in middle-aged and elderly Koreans even at relatively low BMI. It might be appropriate to lower the BMI classification from the current >/=25.0 for overweight and >/=30.0 for obesity for this group of Koreans.