The effect of sugar on behavior or cognition in children. A meta-analysis

Journal Article 1 Mention

M. L. Wolraich•1995

Average · 74th Percentile

38 citations · Public Health, Environmental and Occupational Health

TLDR

Eating sugar did not make children behave worse or think less well in the studies reviewed. Parents’ strong beliefs may reflect expectations, although small effects in some children cannot be ruled out.

Summary

AI Generated

This content was automatically synthesized by Credo's AI models directly from the original source text.

AI summaries can make mistakes — double-check important details against the original source.

1 Study Aim

The study aimed to determine whether consuming sugar changes children’s behavior or thinking ability. The authors tested this question by combining results from earlier controlled studies through a meta-analysis (a statistical review that combines research findings). They also considered whether effects differed across types of behavior, thinking skills, or children. The researchers wanted to clarify whether sugar itself causes noticeable problems for children.

2 Study Design

The authors searched MEDLINE and PsychINFO databases and their own files. They included studies where children consumed a measured amount of sugar or an artificial-sweetener placebo, while children, parents, and staff remained unaware of the condition. Sixteen reports provided 23 within-subject studies, meaning the same children experienced both conditions. The researchers calculated effect sizes (numbers showing the size and direction of differences) across 14 outcome types. The review compared children’s behavior and thinking after sugar with their results after a substitute sweetener.

3 Findings

The study found no meaningful overall effect of sugar on children’s behavior or thinking. Average effect sizes ranged from -0.14 for direct observations to +0.30 for academic tests, but every 95% confidence interval (a range showing uncertainty around an estimate) included zero. The authors suggested that parents’ beliefs may result from expectations and common associations. They stated that small effects, or effects in particular groups of children, could not be excluded. The available evidence does not support sugar as a general cause of poor behavior or reduced thinking in children.

Abstract

Objective. —To examine the effects of sugar on the behavior or cognition of children by using meta-analytic techniques on reported studies. Data Sources. —Studies were identified through a literature search of the MEDLINE and PsychINFO databases and the authors' files using sugar, sucrose, and attention deficit disorder as the search terms. Study Selection. —Studies were required to (1) intervene by having the subjects consume a known quantity of sugar; (2) use a placebo (artificial sweetener) condition; (3) blind the subjects, parents, and research staff to the conditions; and (4) report statistics that could be used to compute the dependent measures effect sizes. Data Extraction. —Variables included publication year, study setting, subject type and number, gender, age, sugar and placebo type and dose, prior dietary condition, measurement construct, means and SDs for the sugar and placebo conditions, and direction of effect. Data Synthesis. —Sixteen reports met the inclusion criteria for a total of 23 within-subject design studies. The weighted mean effect size and related statistics for each of the 14 measurement constructs revealed that although the range for these means was from -0.14 for direct observations and up to +0.30 for academic tests, the 95% confidence interval for all 14 mean effect sizes included 0. Conclusion. —The meta-analytic synthesis of the studies to date found that sugar does not affect the behavior or cognitive performance of children. The strong belief of parents may be due to expectancy and common association. However, a small effect of sugar or effects on subsets of children cannot be ruled out. (JAMA. 1995;274:1617-1621)

Primary Link Archive DOI Openalex