This study was done to analyse the dietary profile of urban south Indian adults. It was also aimed to study, if the dietary profile influenced the glycaemic and anthropometric data. Dietary details were collected in a representative urban sample of 900 study subjects in the epidemiological survey for diabetes conducted in 1995 in the city of Madras. The details were collected by a 24-h recall method. All the dietary factors were similar in the non-diabetic (NGT) and newly diagnosed diabetic cases, but the values were lower in known diabetic cases due to dietary modifications (P < 0.001 for all compared to NGT and new diabetic cases). For further analysis, known diabetic cases were deleted and the rest were combined as one group. Men consumed higher calories (2066+/-437, range 1028-3662 kcal) than women (1745+/-343, range 870-3260 kcal) (P < 0.01). Older persons consumed lower calories and percentages of the proximate principles in diet were proportionately lower. Higher calorie consumption was due to consumption of higher quantities of food and not any specific dietary factor. BMI, WHR, plasma glucose, serum cholesterol and triglycerides were not significantly influenced by the total calorie consumption. Calorie consumption was higher in persons engaged in strenuous physical activity. Total calories and proportionately the proximate principles of diet were less in the high income group. The similarity in diet in the non-diabetic and the newly diagnosed diabetic persons showed that the development of diabetes was probably not related to changes in dietary habits. Lower consumption of calories and carbohydrates by the known cases of diabetes was due to the dietary modifications introduced in the management of the disease. Lower calorie consumption in women and older people could be related to lower physical activity. This study shows a uniform dietary pattern among the different strata of society with minor variations based on age, gender and physical activity. No difference has been noted in dietary habits of the newly diagnosed diabetic subjects and the non-diabetic adults.