Abstract
Obesity is an important pathological basis of major risk factors for atherosclerosis including type 2 diabetes mellitus, dyslipidemia and hypertension. Obesity is also associated with a variety of health problems such as non-alcoholic fatty liver diseases, hyperuricemia or proteinuria. It is thus important how to diagnose obesity and how to determine therapeutic subjects among obese people. Although the number of severe obese subjects in Japan is smaller than those in Western counties, the prevalence of obesity-related diseases is comparable; it therefore appears to be reasonable to diagnose obesity with smaller BMI in Japan. Japan Society for the Study of Obesity (JASSO) defines 18.5 ≤ BMI < 25 as normal weight, 18.5 > BMI as underweight and 25 < BMI as obese on the basis of a number of epidemiological studies. Among obese subjects, JASSO defines subjects who need weight reduction from medical reason as “obesity disease”. Important point is that “obesity disease”includes not only subjects who currently possess obesity-related health problems but also subjects who will develop the health problems with high probability. It is widely accepted that visceral obesity is such high-risk obesity. To diagnose visceral obesity, JASSO recommends the evaluation of visceral fat area (VFA) by CT scan after the screening by waist circumference measurements. Japan Society of Ningen Dock (JSND) released a new reference interval for health checkup, which was determined by clinical and laboratory data of subjects who were free from certain diseases as well as from certain medical treatments. A large number of subjects with visceral obesity who needs weight reduction from medical reason fall in this newly-released reference interval for BMI (< 27.7). Health professionals who engage in health checkups should understand the difference of the scientific basis as well as the objective of the criteria of obesity by JASSO and the reference interval of JSND.
