Food consumption of 177 rural and 94 urban subjects (98 aged 12 years, 105 aged 35-44 years, and 68 aged 65-74 years) was studied in rural and urban Ilala district, Dar-es-Salaam, Tanzania, to characterize rural-urban differences in the meal and snack patterns and intakes of energy and nutrients. Food consumption of each subject was studied using 24 h dietary recall once during the rainy season and once during the dry season. Micro Nutrica PC database, expanded with East African food composition tables, was used in the nutrient intake analyses. All urban and 92% of rural subjects had three daily meals, and snacks were as commonly eaten in both areas of the survey. Foods of animal origin, e.g. meat and milk, were seldom used by the rural subjects. The WHO/FAO recommended minimal daily allowances of energy and protein were not reached by 26 and 15% of the rural subjects, respectively (10 and 4% of the urban subjects). Mean intake of folic acid by rural subjects was clearly below that of the urban subjects. Intakes of sucrose, mono- and disaccharides combined, polysaccharides, fibre and cholesterol differed markedly in all age groups in rural and urban circumstances (P < 0.05). Intake of fat and saturated fat was extremely low in all age groups, particularly in the rural subjects. The data suggest that (sub)clinical protein-energy malnutrition is prevelant in Tanzania, and that the high intakes of sucrose and cholesterol and the low intake of fibre by the urban subjects may increase the prevalence of dental caries and cardiovascular diseases in that population.