Perspective on diagnostic criteria for obesity and abdominal obesity in Korean adults

Excessive body weight is associated with increased health risks in humans. In general, the risk of mortality increases with greater obesity. The 2018 guideline for the management of obesity by the Korean Society for the Study of Obesity proposed the body mass index (BMI) cut-off levels of 25 kg/m² and 23 kg/m² as diagnostic criteria for obesity and overweight (pre-obese) in Korean adults, respectively. Abdominal obesity has been defined as waist circumference (WC) ≥90 cm in men and WC ≥85 cm in women. In this review, the validity of these criteria for Korean adults was examined based on the evidence regarding the associations of obesity index with mortality and morbidity. The American Association of Clinical Endocrinologists/American College of Endocrinology algorithm and American Diabetes Association guideline for the medical care of obese and overweight patients support a BMI of 25 kg/m² and 23 kg/m², respectively, as the cut-off levels for Asians (and some ethnicities) corresponding to the BMI values of 30 kg/m² and 25 kg/m², respectively, for Caucasians. In the future, the optimal cut-off levels for obesity and abdominal obesity may require adjustment as the demographic characteristics of the Korean population change. In addition, development of more valid indicators that better reflect health risks of obesity is needed.