Associations between dietary intake and cognitive performance were examined in 260 elderly people aged 65-90 y who were free of significant cognitive impairment. Dietary intake was monitored with a weighed-food record for 7 consecutive days. The subjects' cognitive capacity was tested by using Folstein et al's Mini-Mental State Examination (MMSE) and Pfeiffer's Mental Status Questionnaire (PMSQ). Subjects with adequate MMSE results (> or = 28 points) had lower intakes of monounsaturated fatty acids, saturated fatty acids, and cholesterol, and higher intakes of total food, fruit, carbohydrate, thiamine, folate, and vitamin C compared with those with less satisfactory results. Subjects who made no errors on the PMSQ had greater intakes of total food, vegetables, fruit, carbohydrate, fiber, folate, vitamin C, beta-carotene, iron, and zinc, and lower intakes of saturated fatty acids compared with those who made errors. Our results agree with those of other authors indicating that intakes of different nutrients or the consumption of a more satisfactory global diet is associated with better cognitive function in the elderly. However, more research is required to determine whether differences in intake of a particular nutrient are the result of or a conditioning factor for incipient impaired cognition. Unmeasured confounding factors may also affect both dietary intake and risk of cognitive impairment. A diet with less fat, saturated fat, and cholesterol, and more carbohydrate, fiber, vitamins (especially folate, vitamins C and E, and beta-carotenes), and minerals (iron and zinc) may be advisable not only to improve the general health of the elderly but also to improve cognitive function.