Dietary, biochemical, and behavioral factors, and breast cancer risk among Asian Indians in India versus Caucasians and Asian Indians in the U.S.A.

The purpose of this study was to examine the influence of diet, biochemical indices, and behavior on breast cancer risk, among cases and controls of Asian Indians in India, Asian Indians in the U.S.A., and Caucasians in the U.S.A., as well as to explore the differences within and among these groups. Dietary assessment was carried out using a 226-item food frequency questionnaire and 4-day food diaries. Fasting blood samples were drawn from subjects and analyzed for total serum cholesterol, high density lipoproteins, triglycerides, ascorbic acid, alpha, gamma, and delta tocopherol, and retinal. The laddering technique was employed to investigate motives and goals that drive food choice behavior. The results of this study suggested that breast cancer (BC) risk factors were not identical for Asian Indians versus Caucasians. Most previously known BC risk factors such as education, smoking, nulliparity, and family history of cancer were not significantly different between BC cases and controls of either country in this study. More specifically however, the results supported an increased risk of BC associated with increased intakes of total fat, monounsaturated fatty acids, and lower intakes of vitamin C, for both Asian Indians and Caucasians. Simultaneous analyses of paired variables across the quartiles of nutrient intake, revealed an increased incidence of BC with low dietary total fiber, crude fiber, and polyunsaturated fatty acids. The Asian Indians in this study also had an increased risk of BC with higher intakes of polyunsaturated fatty acids, lower intakes of carbohydrate, and lower serum concentrations of both ascorbic acid and high density lipoproteins. Higher caffeine intake was also associated with increased risk of BC among Caucasians only. The immigrant Asian Indians in the U.S.A. had significantly lower protein and higher carbohydrate intakes compared to Caucasian controls, however, with the exception of alpha-tocopherol dietary vitamins A, C, E, and beta-carotene were not significantly different from Asian Indian controls living in India. Additionally, motivation of food choice was distinctly different between BC cases and controls. The BC cases showed a lack of health related motives of food choice behavior. Overall, this lack of interest in health among cases in general, was inversely associated with higher intakes of total fat, and lower intakes of fiber and vitamin C compared to controls in this study.