Westernized food habits and concentrations of serum lipids in the Japanese

To investigate the association of westernized food habits and concentrations of serum lipids in the Japanese, we studied 1200 healthy Japanese living in Hiroshima prefecture and 1483 ethnic Japanese from Hiroshima prefecture living in the Hawaii Islands and Los Angeles. The nutritional assessments were made by the same dietitians. No major difference was observed in the total energy intake between the Japanese and the Japanese-Americans in both males and females. However, the intake of animal fat and simple carbohydrates (especially fructose) were markedly greater, and that of complex carbohydrates lower, in the Japanese-Americans compared with the Japanese. The mean serum cholesterol (CH), LDL-CH and serum triglyceride (TG) levels were significantly higher in the Japanese-Americans in both sexes. The mean HDL-CH concentration was similar between the two groups in males, but it was approximately 7 mg/dl higher in Japanese-American females. Using the 75 percentile values of CH and TG in the Japanese in Hiroshima, the frequency of WHO types IIa and IIb hyperlipidemia was about twice as high in the Japanese-Americans. These results suggest that westernized food habits in the Japanese include qualitative changes in animal fat, simple carbohydrate and complex carbohydrate diet rather than an increase in the total energy intake. These changes are associated with marked increases in the concentrations of serum CH and TG and increased prevalence of types IIa and IIb hyperlipidemia.