The results of the UK Child Dental Health Survey of 1993 indicated that dental erosion was a problem in children, with acidic dietary components thought to be the main etiological factor. The aim of this study was to compare, in the form of a case control study, the diets of children with dental erosion with those who were caries-active or caries-free. Structured dietary histories were taken from 309 age and gender matched children to determine the type and frequency of intake of acidic foods and drinks, together with any drinking habits that prolonged exposure of the teeth to dietary acids. Results showed that the children with erosion drank acidic beverages significantly more frequently than children who either had caries or were caries-free. Children with erosion also drank milk or water significantly less often than the control groups, and were more likely to have a swishing or holding habit associated with drinking. Fruit and vinegar consumption was higher in the erosion group, as was the taking of vitamin C supplements. The results of this study suggest that the increased consumption of acidic foods and drinks, particularly when associated with a swishing or holding habit, may contribute to the development of erosion in some children. Dietary advice should emphasize the dangers of a highly acidic as well as that of a cariogenic diet.