Epidemiology of obesity and public health strategies for its control in Japan

Obesity has become a public health problem in Japan. The National Nutrition Survey (2000) showed prevalence of preobese (body mass index: 25−29.9 kg/m 2 ) and obesity (≥ 30 kg/m 2 ) was 24.5% and 2.3%, respectively, in males, and 17.8% and 3.4%, respectively, in females aged 20 years and over. Trends in prevalence of overweight in the last 25 years differed among age‐sex groups and across residential areas. The most significant increase in overweight was observed in men in small towns, whilst there was a remarkable decrease in women in metropolitan areas. In the 10 year national plan for health promotion named ‘Health Japan 21’, maintaining appropriate body weight (obesity control and prevention of thinness brought about by dieting in young women) is a core component of the prioritized issues. Increasing the number of people who know their healthy body weight and practice weight control is also listed as an important objective. The proportion of people engaged in regular exercise for health and following the recommended average number of steps in daily life is a major indicator for evaluation of the program. We conclude that when formulating effective public health strategies for obesity control, it is important to consider each country's own situation related to obesity issues including the proper BMI cutoff point, which might be much different from that in western societies.