The influence of diet and sampling site on subcutaneous adipose-tissue fatty acid composition and vitamin E content was examined in 20 healthy subjects. A dietary history and adipose-tissue biopsies from the buttock were obtained from 14 individuals. In another six individuals, samples were taken from both waist and buttock. The relative dietary intake of both polyunsaturated and saturated fatty acids correlated with the relative content in adipose tissue (r = 0.6, p = 0.02). Adipose-tissue vitamin E was strongly associated with dietary intake (r = 0.76, p = 0.004). The content of n - 3 (omega-3) fatty acids in adipose tissue was shown to influence adipose-tissue vitamin E negatively. Waist and buttock fat differed (p less than 0.05) with regard to fatty acid composition whereas no systematic variation was seen in the vitamin E content. The use of adipose-tissue biopsies in epidemiologic studies as measures of the habitual relative intake of fatty acids and vitamin E is suggested.