Overweight is associated with decreased cognitive functioning among school-age children and adolescents.
OBJECTIVE
Childhood overweight and obesity have increased substantially in the past two decades, raising concerns about their psychosocial and cognitive consequences. We examined the associations between academic performance (AP), cognitive functioning (CF), and increased BMI in a nationally representative sample of children.


METHODS
Participants were 2,519 children aged 8-16 years, who completed a brief neuropsychological battery and measures of height and weight as a part of the Third National Health and Nutrition Examination Survey, a cross-sectional survey conducted between 1988 and 1994. Z-scores were calculated for each neuropsychological test, and poor performance was defined as z-score <2.


RESULTS
The association between BMI and AP was not significant after adjusting for parental/familial characteristics. However, the associations between CF remained significant after adjusting for parental/familial characteristic, sports participation, physical activity, hours spent watching TV, psychosocial development, blood pressure, and serum lipid profile. Z-scores on block design (a measure of visuospatial organization and general mental ability) among overweight children and children at risk of overweight were below those of normal-weight children by 0.22 (s.e. = 0.16) and 0.10 (s.e. = 0.10) unit, respectively (P for trend <0.05). The odds of poor performance on block design were 1.97 (95% confidence interval: 1.01-3.83) and 2.80 (1.16-6.75), respectively, among children at risk or overweight compared to normal-weight peers.


CONCLUSIONS
Increased body weight is independently associated with decreased visuospatial organization and general mental ability among children. Future research is needed to determine the nature, persistence, and functional significance of this association.
Li
Yanfeng
Y
Department of Epidemiology and Biostatistics, the Arnold School of Public Health, University of South Carolina, South Carolina, USA.
Dai
Qi
Q
Jackson
James C
JC
Zhang
Jian
J
D000293:Adolescent; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology; D002648:Child; D003071:Cognition / Q000502:physiology*; D003072:Cognition Disorders / Q000150:complications*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009749:Nutrition Surveys; D050177:Overweight / Q000150:complications* / Q000503:physiopathology* / Q000523:psychology; D011584:Psychology; D012959:Socioeconomic Factors; D014481:United States