Nutritional risk factors of Havasupai women

Abstract

The Havasupai tribe (n=423) is a geographically isolated, homogeneous population living at the south rim of Grand Canyon Park, AZ. The purpose of this study was to assess the dietary intakes of adult Supai women to identify those nutritional factors that might contribute to the high rates of obesity and noninsulin dependent diabetes mellitus (NIDDM) seen among tribal members. 24-hr recalls were collected from a preliminary sample of 26 women (33±9y) and analyzed for nutrient intake. Although diabetic status was not documented, 25 of 26 subjects were classified as obese (BMI>32.3 or > 95th percentile NHANES II data). Twenty-two subjects had a waist-to-hip ratio greater than 0.8, indicative of abdominal obesity. Mean (±SD) caloric intake was 2462±922 kcal/d, a mean energy intake of 27.8 kcal/kg body weight. On average, 37% of kcal came from fat (13% of kcal from saturated fat), 50% from carbohydrate (23% of kcal from sugar) and 13% of kcal from protein. Despite frequent alcohol abuse among Supai men and women, no subject reported any alcohol consumption, thus total caloric intake may be underreported. Although mean intakes of calcium (642±394 mg/d), iron (13.7±6.4 mg/d), zinc (11.8±4.8 mg/d), folate (209±170 ug/d), Vitamin B-6 (1.3±0.6 mg/d), Vitamin C (84±88 mg/d) and Vitamin A (624±1037 RE/d) were above two-thirds the RDA for adult women, large intakes of these nutrients by a few individuals obscured the deficient intakes of the other subjects. For example, Vitamin A intake fell below 2/3 RDA for 73% of subjects, while 42% of the women failed to consume 2/3 RDA for calcium. The items making the greatest contributions to energy and nutrient intakes in these subjects were often processed and fortified foods. Vitamin C fortified powdered drink mixes contributed almost 40% of the dietary Vitamin C. Soda pop, drink mixes, corn chips, and boxed macaroni and cheese were among the top six items contributing to total caloric intake (ground beef and fried potatoes were the other two foods). The overall variety of foods consumed by these subjects was very limited, reflecting the limited stock of the tribal store and the difficulty in bringing in foodstuffs from outside the reservation. Pinto beans and corn tortillas were the only reported food items typical of the traditional Supai diet. In conclusion, this sample of Havasupai women consumed a diet high in total and saturated fat, high in refined sugar and low in fiber. Food choices were limited in variety and often highly processed. Each of these factors may have contributed to the prevelance of obesity and NIDDM currently seen in the Havasupai population.