But my students really are wilder after parties. Why?

Most likely the party itself: excitement, friends, games and a broken routine. The blinded studies separate sugar from all of that and find no effect of sugar on behavior.

Could some children be sensitive to sugar?

The meta-analysis authors say a small effect, or an effect on some children, can't be ruled out. But the trial that recruited children whose parents described them as sugar-sensitive found no differences on any of 39 measures.

Does this mean I should hand out candy as a reward?

No, and this page isn't about whether sugar is healthy. There are good reasons to prefer non-food rewards, from allergies to family rules. The point is only that sugar isn't the cause of a lively afternoon.

Is this related to ADHD?

These studies tested whether eating sugar changes children's behavior over hours or weeks, not what causes ADHD, which is diagnosed by professionals. This page isn't medical advice; talk with the family and your school team about any child's needs.

Does sugar make kids hyper?

The claim: “Sugar makes children hyperactive.”

Evidence for the claim Contradicted3 sourcesChecked October 2026

What the research says about the claim

Strong
Promising
Mixed
Thin
Contradicted

Contradicted. A meta-analysis of blinded studies, where neither children nor adults knew who had eaten sugar, found sugar did not affect children's behavior or thinking. A double-blind trial that put children described as sugar-sensitive on high-sugar diets for weeks found no differences on any of 39 measures. And when mothers were told their sons had eaten sugar, though every boy had a placebo, they rated them as more hyperactive. The expectation changes what adults see.

Rated Contradicted. No rigorous study supports it. Three rigorous studies found no effect or the opposite. How we rate the evidence

Checked against each source in October 2026.

The studies behind this rating

Wolraich et al. (1995)Meta-analysisNo effect
Across blinded studies in which children ate a known amount of sugar or a sweetener placebo, sugar did not affect children's behavior or cognitive performance. The authors suggest parents' strong belief may come from expectation and association, and say a small effect, or effects on some children, can't be ruled out.
Sample 23 blinded, placebo-controlled studies from 16 reportsWho School-age childrenRead it at the source (opens in a new tab)
Wolraich et al. (1994)Randomized trial in schoolsNo effect
In a double-blind trial, children described by their parents as sensitive to sugar showed no significant differences on any of 39 behavior and learning measures between a high-sugar diet and diets sweetened with aspartame or a placebo sweetener. Preschoolers differed on only a few measures, with no consistent pattern.
Sample 25 preschool children and 23 school-age children described by parents as sensitive to sugar, each on three diets for three weeksWho School-age childrenRead it at the source (opens in a new tab)
Hoover & Milich (1994)Randomized trial in schoolsContradicts
Shows where the belief comes from: mothers told their son had eaten a lot of sugar (he hadn't; every boy got a placebo) rated him as more hyperactive, and watched and corrected him more.
Sample 35 boys aged 5 to 7 described as sugar sensitive, and their mothers, randomly assignedWho School-age childrenRead it at the source (opens in a new tab)

Where the idea came from

The belief is common, especially among parents, and it seems to match experience: children at birthday parties and class celebrations are often wild. Sugar became the obvious explanation, and the phrase "sugar high" made it sound like a fact about the body.

To test it fairly, researchers have to separate sugar from everything that comes with it (excitement, a party, a change of routine) and from what adults expect. That means blinded studies: children get either sugar or a sweetener that tastes the same, and neither they, their parents nor the researchers know which.

What the research says

Mark Wolraich, David Wilson and Wade White pooled 23 such blinded, placebo-controlled studies in a 1995 meta-analysis published in JAMA. Across fourteen kinds of measure, from direct observation of behavior to academic tests, none showed a reliable effect of sugar. They concluded sugar doesn't affect children's behavior or cognitive performance, noting that a small effect, or an effect on some children, can't be ruled out.

A year earlier, Wolraich and colleagues had run a demanding trial. Preschool children, and school-age children whose parents described them as sensitive to sugar, followed three diets for three weeks each: high in sugar, sweetened with aspartame, or sweetened with a placebo sweetener. Nobody knew which diet was which. For the children described as sugar-sensitive, there were no significant differences on any of 39 behavior and learning measures. For the preschoolers, only a few measures differed, with no consistent pattern.

Daniel Hoover and Richard Milich tested the other explanation. Boys aged five to seven whose mothers described them as sugar-sensitive all drank a sugar-free placebo. Half the mothers were told their son had just had a large dose of sugar. Those mothers rated their sons as significantly more hyperactive, and stayed closer to them and corrected them more, than mothers told the truth.

Why it hangs on

The parties are real. Children often are more excited at celebrations, but the excitement comes with the party: friends, games, noise, a break from routine. Sugar happens to be there too.

Expectation shapes what we see. Hoover and Milich's study shows that adults who believe a child has eaten sugar see more hyperactivity, even when there was none. The belief is self-confirming.

It's a convenient explanation. "Too much sugar" is an easier story than "too much excitement and too little structure", and it suggests a simple fix.

What to do instead

For a calmer celebration or afternoon, change what actually drives behavior:

Keep structure: a clear plan for the party, set times, and a calm activity before transitions.
Plan transitions back to work with a signal and a short settling routine; our calm brain breaks help.
Use non-food rewards if you'd rather not hand out candy; there are good reasons (allergies, family rules, health) that have nothing to do with hyperactivity. Our list of classroom reward ideas that aren't candy has forty.

This page is about behavior and learning only. It isn't health or nutrition advice, and it doesn't mean sugar is good for children; follow your school's nutrition policies and families' wishes.

Questions teachers ask

But my students really are wilder after parties. Why?: Most likely the party itself: excitement, friends, games and a broken routine. The blinded studies separate sugar from all of that and find no effect of sugar on behavior.
Could some children be sensitive to sugar?: The meta-analysis authors say a small effect, or an effect on some children, can't be ruled out. But the trial that recruited children whose parents described them as sugar-sensitive found no differences on any of 39 measures.
Does this mean I should hand out candy as a reward?: No, and this page isn't about whether sugar is healthy. There are good reasons to prefer non-food rewards, from allergies to family rules. The point is only that sugar isn't the cause of a lively afternoon.
Is this related to ADHD?: These studies tested whether eating sugar changes children's behavior over hours or weeks, not what causes ADHD, which is diagnosed by professionals. This page isn't medical advice; talk with the family and your school team about any child's needs.

Cite this page

Peabody Teach. (2026, October 29). Does sugar make kids hyper?. https://teach.peabody.kids/library/myths/sugar-makes-kids-hyper

The meter rates the evidence for the claim: Contradicted means rigorous studies find it false. Written by Peabody Teach from the sources above, read at the source. Something wrong? Tell us.