The effects of sugar (sucrose) on the behavior of 30 preschool children (20 boys and 10 girls, mean age 5 years 4 mos) and 15 elementary school children (6 boys and 9 girls, mean age 7 yrs 2 mos) were investigated by psychologists from Colorado State University, Fort Collins, CO, and the Univ of Mississippi Med Cntr, Jackson, MS. Parents and teachers questioned before the study complained that the child was behaviorally sensitive to sugar in approx 50% of subjects. Two preschool children had been considered hyperactive by the school director. A basic breakfast included a 4 oz orange flavored drink of high sucrose content (50g), low-sugar (6.25g) or aspartame (122 mg), randomly selected, 5 days on each, using a double-blind control design. The mean sucrose intakes for the high, low, and “control“ aspartame conditions were 2.26, 0.28, and 0.00 g/kg, respectively, and the total carbohydrate contents of breakfast averaged 3.95, 1.88, and 1.54 g/kg, respectively.
On cognitive measures, girls made significantly more errors on a paired-associate learning task performed 20-30 min following a high-sugar content breakfast when compared to a low-sugar meal, whereas boys were unaffected. On global ratings, younger preschool children were affected differently than older children. On an Abbreviated Conners Teacher Rating Scale completed before lunch, both boys and girls were more active in behavior after the high sugar meal than that of low sugar content. Measures of behavior by observation for fidgetiness, change in activity, running, vocalization and aggressiveness and other cognitive measures involving matching and academic tasks failed to demonstrate changes after sugar ingestion. 
COMMENT. Evidently, the effects of sugar on children’s behavior is not yet resolved. This study demonstrates significant adverse effects although the authors conclude that these are minimal in degree. Certain limitations of the study design are admitted: 1. The sugar challenge dose was the same for all subjects and younger and smaller children, affected differently, received larger amounts than did older and larger children. The design was not adequate to pinpoint the amount of sugar that may cause deleterious effects. 2. The prior dietary history of the subjects was unknown, and those accustomed to consuming large amounts of sugar may have reacted differently from children who usually ate low sugar meals. 3. The assumption that aspartame used as a control is innocuous may not be correct (see Ped Neur Briefs Nov 1987;1:45). Further work on possible behavioral effects of sucrose is clearly indicated. The only proven contraindication to excess sugar in a child’s diet is that emphasized by the dental profession.