OBJECTIVE—To determine the long-term effect of low glycemic index dietary advice on metabolic control and quality of life in children with type 1 diabetes. RESEARCH DESIGN AND METHODS—Children with type 1 diabetes (n = 104) were recruited to a prospective, stratified, randomized, parallel study to examine the effects of a measured carbohydrate exchange (CHOx) diet versus a more flexible low–glycemic index (GI) dietary regimen on HbA1c levels, incidence of hypo- and hyperglycemia, insulin dose, dietary intake, and measures of quality of life over 12 months. RESULTS—At 12 months, children in the low-GI group had significantly better HbA1c levels than those in the CHOx group (8.05 ± 0.95 vs. 8.61 ± 1.37%, P = 0.05). Rates of excessive hyperglycemia (>15 episodes per month) were significantly lower in the low-GI group (35 vs. 66%, P = 0.006). There were no differences in insulin dose, hypoglycemic episodes, or dietary composition. The low-GI dietary regimen was associated with better quality of life for both children and parents. CONCLUSIONS—Flexible dietary instruction based on the food pyramid with an emphasis of low-GI foods improves HbA1c levels without increasing the risk of hypoglycemia and enhances the quality of life in children with diabetes.