Television exposure and overweight risk in preschoolers

To test the independent effect of television exposure in preschool-aged children on overweight risk.

Cross-sectional and longitudinal analysis of the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development.

Ten US sites.

One thousand sixteen children selected via conditional random sampling.

Being awake in the room with the television on for 2 hours or more per day, by maternal report at age 36 months.

Child overweight (body mass index [calculated as weight in kilograms divided by the square of height in meters] > or =95th percentile) calculated from measured anthropometrics at ages 36 and 54 months. Covariates tested included child sex and race; maternal marital status, education, age, and depressive symptoms; income-needs ratio, child behavior problems; Home Observation for Measurement of the Environment total score; hours per week in nonparental care; and proportion of television exposure that was educational.

At age 36 months, 5.8% of children were overweight; at age 54 months, 10.0% were overweight. Exposure to 2 or more hours of television per day was associated with an increased risk of overweight at both age 36 months (odds ratio, 2.92; 95% confidence interval, 1.36-6.24) and age 54 months (odds ratio, 1.71; 95% confidence interval, 1.03-2.83) in unadjusted analyses. Only maternal age altered the concurrent relationship, and the effect of television remained significant (odds ratio, 2.61; 95% confidence interval, 1.21-5.62). Television exposure at age 36 months was no longer a significant predictor of overweight at age 54 months when controlling for covariates.

Excessive television exposure is a risk factor for overweight in preschoolers independent of a number of potential confounders associated with the quality of the home environment.