Trends in diet, physical activity and health in remote Alaska native communities undergoing rapid Westernization

Andrea Bersamin
Nutritional Biology, University of California, Davis
July, 2006
 

Abstract
The objective of this dissertation was to identify risk factors for chronic disease in Yup'ik Eskimos transitioning from a traditional-subsistence to a Western lifestyle. The underlying hypothesis was that a Westernizing diet and lifestyle would be associated with an increased risk of chronic disease.

A pilot study was conducted to determine the utility of the Healthy Eating Index (HEI) to measure the diet quality of a modem Alaska Native (AN) diet. Twenty-four hour recalls were collected from 48 male and 44 female Yup'ik Eskimos (14-81 years old) in 3 remote AN villages. Despite similar nutrient intakes, youth scored significantly higher on the HEI than elders. The diet of 63% of participants was classified as poor. Although the HEI serves to identify areas of concern with respect to diet quality, it is limited in its ability to detect the positive value of traditional foods.

A larger survey examined the impact of a Westernizing diet on fat intake, red blood cell fatty acid composition, and health among 530 Yup'ik Eskimos (14-94 year olds). Diet was assessed with a 24-hour recall and a 3 day food record. Traditional food intake was positively associated with age, total fat, EPA, and DHA intake. Participants consuming more traditional foods derived a significantly smaller proportion of their dietary fat from saturated fats (P<0.001). Analyses of red blood cell fatty acid composition supported these findings. After multivariable adjustment, traditional food intake was significantly positively associated with HDL concentration and significantly negatively associated with triglyceride concentration (P<0.001). The effects of a change in dietary fatty acid composition may disproportionately affect youth, who have a more commercially based Western diet.

The utility of using pedometers to assess physical activity was determined in a sub-sample of participants (n= 259). Among women, mean steps/day were inversely correlated with measures of adiposity (r = -0.34 to -0.37, P <.01), controlling for age. Fasting glucose was inversely (r = -0.30, P = 0.01) and HDL-C concentration was positively associated pedometer counts (r = 0.23, P = 0.03). Findings support the construct validity of using pedometers to measure physical activity in a Westernizing Alaska Native population.