OBJECTIVE To assess the nutritional adequacy of low-fat, low-saturated fat, low-cholesterol-modified diets of children with hyperlipidemia. METHODS Case comparison study. METHODS Tertiary care ambulatory pediatric atherosclerosis prevention center. METHODS White middle-class suburban children. Subjects were 54 consecutive children with hyperlipidemia (26 boys) with a mean (+/- SD) age of 10.8 +/- 3.4 years. Controls were 44 healthy children (19 boys) aged 10.8 +/- 0.9 years recruited from a local elementary school. METHODS The subjects received individual nutrition counseling on a National Cholesterol Education Program Step I Diet from a registered dietitian. METHODS The 3-day written food records were analyzed by a registered dietitian using the Minnesota Nutrient Data System. Outcome measures were intakes of energy, fat-soluble vitamins, and minerals as a percentage of the Recommended Dietary Allowance. The means between cases and controls were compared by Student's t test. RESULTS There was no significant difference in consumption of energy, minerals, or vitamins D and E between the groups. The control group's diet contained significantly greater amounts of fat, saturated fat, and cholesterol. The children with hyperlipidemia consumed significantly more vitamin A (P < .005). CONCLUSIONS The nutrient quality of fat- and cholesterol-modified diets of children who have received nutritional counseling compares favorably with the nutrient quality of controls on an unrestricted diet. Therefore, pediatricians can prescribe with confidence a Step I Diet for children with hyperlipidemia and adolescents when nutritional counseling is available.