Diet among Siberian Yup'iks of Alaska and the implications for cardiovascular disease

Abstract

I investigated dietary factors associated with cardiovascular disease and their relation to blood lipids among Siberian Yup'iks. This study was prompted by reports of increasing mortality from cardiovascular disease in Alaska Natives and the need to know to what extent their unique diet may influence cardiovascular disease. Information on dietary intakes was collected in 1992 using two recall methods, from over one-half of the Siberian Yup'ik Eskimos (n = 65) $\geq$40 years-of-age in Gambell, Alaska, as part of a comprehensive screening for diabetes and cardiovascular disease. Based on analysis of 29 nutrients, mean daily intakes of monounsaturated fats and antioxidants--vitamin E, selenium, and vitamin C (among men)--exceeded US recommendations. Mean intake of n-3 fatty acids (7.0 g/d) exceeded the level associated with favorable physiologic responses (>3 g/d) and was comparable to that of Greenlandic Eskimos (8.6 g/d). Although fat intake was high (44% of total energy for men, 42% for women), saturated (11%) and polyunsaturated fats (8%) were not different $(P>$ 0.05), but energy from monounsaturated fat was greater (18% vs. 13%, $P<$ 0.001) than the general US population (NHANES III). Native foods, including walrus, seal and whale, contributed 25% of the energy, >50% of the protein, n-3 fatty acids, arachidonic acid, cholesterol, iron and vitamin B-12, and all of the eicosapentaenoic acid. Nonnative foods were frequent sources of saturated fats. Mean intakes of saturated fat and cholesterol exceeded recommendations. Correlations between foods and blood cholesterol, LDL, HDLI triglycerides and LDL-HDL ratio produced differences by age and sex. Multicollinearity occurred among several nutrients, including $\alpha$-tocopherol and n-6 fatty acids (r = 0.888). When multiple regression was applied among all participants, $\alpha$-tocopherol and fresh bird were associated with reduced LDL-HDL ratio; body-mass index, pizza and syrup were positively associated. Adding obesity to this equation increased the percent of variation explained (42% to 59%). Dietary advice includes maintaining desirable weight, consuming a diet moderate in fat, rich in monounsaturated fats and low in saturated fats, and foods rich in n-3 fatty acids--e.g. Native foods--and vitamin E.