Eating habits, activity, lipids and body mass index in Japanese children: The Shiratori Children Study

OBJECTIVE: To describe the eating habits and physical activity of Japanese children aged 10 y, and to investigate their relationship to lipids and body mass index (BMI); also to study the relationship between BMI and lipids in these children. DESIGN: This was a cross-sectional study conducted at six schools in Shiratori, Japan during 1992-1994. Physical examinations and questionnaires were used to collect data from 457 fifth grade children, aged 10 y. RESULTS: The diet of these children was mixed, with Japanese and Western foods almost equally reported. Boys were more active than girls. More active children had higher high density lipoprotein cholesterol (HDL-C), and children who ate a more Japanese diet had slightly lower HDL-C. BMI was positively related to cholesterol, low density lipoprotein cholesterol (LDL-C), triglycerides and inversely related to HDL-C. The amount of rice intake was positively associated with the BMI of these children. CONCLUSION: In our study of Japanese children aged 10 y, their diets were fairly Westernized, and most children were fairly inactive based on our activity score. Although obesity is low in these young Japanese subjects (14.1%), children who were obese (BMI > 20) had worse lipid profiles than those who were not obese. An exceptionally high rice intake was associated with obesity, and thus may be an early warning sign for future obesity.