In Western populations, about a third of elderly women have gallstones, as assessed from ultrasonography. In South Africa, cholelithiasis is reported to be increasing in urban blacks. Their recent dietary changes include a rise in fat and a fall in dietary fiber intake. To assess the current situation, we have carried out ultrasonography studies on 100 urban black women, 55-85 yr old, with no clinical evidence of gastrointestinal disease, especially with reference to the biliary system. Ten patients (10%) were positive. There was no association with parity. Their body mass index (27.8 +/- 6.9) was significantly higher (P less than 0.05) than those who were negative (25.7 +/- 6.1). From dietary intake assessments, there were no significant differences between those positive and negative with respect to mean intakes of energy, protein, fat, carbohydrate, dietary fiber or sugar (p greater than 0.05). Continuing exposure to a western lifestyle would be expected to increase prevalences of gallstones.