Our pilot study compared the short-term glycemic effects of a traditional "sucrose free" diet (Suc-Free, 2% total calories from sucrose) to a sucrose-containing diet (Suc-Con, 10% total calories from sucrose) in a clinical research center. Both weighed diets were isocaloric and included 50% carbohydrate, 30% fat, and 20% protein in three meals and three snacks; glucose, fructose, and dietary fiber were identical. Sucrose isocalorically replaced complex carbohydrate at each meal and for the afternoon snack. Ten children (7 to 12 years of age; mean total hemoglobin A1 level 8.9 +/- 0.3%) were randomly assigned, in a crossover design, to one of the two orders (Suc-Free followed by Suc-Con or Suc-Con followed by Suc-Free) for consecutive 2-day diet periods; insulin doses remained constant. Preprandial and postprandial blood glucose levels were measured for each meal and snack (18 measurements per day). To account for baseline differences, we calculated the change in blood glucose levels from baseline to 30 minutes and 1 hour for each meal and snack (mean +/- SEM). No differences were detected between diets. Total area under the glucose response curve (levels measured hourly from 8 AM to 9:30 PM in milligrams per deciliter) was not significantly different for the two diets (Suc-Free 3672 +/- 240; Suc-Con 3574 +/- 285; p = 0.74). No difference in 24-hour urinary glucose levels (measured in grams per day) was detected between the two diets (Suc-Free 35.6 +/- 7.5; Suc-Con 34.5 +/- 7.5; p = 0.84). Incidences of hyperglycemia that required supplemental short-acting insulin and of mild hypoglycemia were similar for both diet periods. Thus, in a controlled setting and during a short study period, children with insulin-dependent diabetes mellitus had a similar glycemic response to diets with and without a moderate amount of sucrose.