NEW YORK (Reuters) -- A study of Japanese-Americans found that those who stick with a low-fat Japanese diet and active lifestyle have lower rates of diabetes than those who don't.
"Japanese-American men in Hawaii who tended to retain a more Japanese lifestyle were less likely to have diabetes," says the University of Hawaii study. "These men were observed to have been more physically active, and their diet consisted of more carbohydrates and less fat, as well as reduced animal protein intake."
Previous studies had compared Japanese-Americans' diabetes risk with those of Japanese citizens, but this is the first to study how health is affected by an Asian immigrant's transition to western lifestyle habits. The researchers studied 8,000 Japanese-American men over 60 years of age, and questioned them about diet, exercise, and years of residence in both the U.S. and Japan.
They found that of the close to 500 diabetics uncovered by the study, just 20% were born in Japan. The more than 400 other diabetics were born in Hawaii -- and had adopted more western lifestyles.
"The Japanese-American men who had an Oriental diet were less obese and more physically active," say study authors, and "had a lower prevalence of diabetes."
They noted a high consumption of low-fat, high-carbohydrate foods such as rice, tofu, and fish in those on an Oriental diet. "The men who retained a Japanese lifestyle were found to have less fat and animal protein intake, but more carbohydrate intake than the men who did not."
Getting daily calories from carbohydrates -- such as rice and pasta -- has been shown in the past to be healthier than obtaining calories from fat. "The diabetic men were consistently observed to have more fat intake" than non-diabetics.
Exercise tended to be an integral part of the routine of those who adhered to a more Asian lifestyle. "These men were observed to have been more physically active," the author state. "More physically active populations tend to have a lower prevalence of diabetes."
Both lack of exercise and a high-fat diet can lead to obesity. And, as the study points out, "more diabetes was observed in the more obese men."
Time spent in Japan seemed to have an effect on lifestyle choices -- and on diabetes rates as well. Of the same group of nearly 500 Japanese-American diabetics, almost 70% had never lived in Japan. The study found that those with less Japanese residency had higher fat intake, exercised less, and were more obese.
Researchers "observed that the Oriental diet-type was observed much more frequently ...in the Japanese-American men who were born in Japan, or who lived in Japan longer."
The immigrant experience, at least for Japanese-Americans, may affect health as dietary and lifestyle choices become more westernized. "It is reasonable to assume that Japanese-American men in Hawaii who did not live in Japan for many years were predisposed to adopt a western diet," researchers conclude.
SOURCE: American Journal of Epidemiology (1996;144(7):674-681)
