Longitudinal Associations between Preschooler TV Exposure, Dietary Intake, and Obesity: Can Parental Media Monitoring Strategies Mitigate Risk?

Background and Purpose: Exposure to TV is a well-established risk factor for obesity among older children but effects among preschoolers remain unclear. TV consumption in early childhood may impede healthy eating through TV marketing of unhealthful food to children and TV’s behavioral priming influence that is known to increase snacking and eating in the absence of hunger. The purpose of this longitudinal study was to characterize TV exposures in early childhood and examine their effects on diet and BMI and putative protective parenting strategies. We hypothesized that: (1) TV exposures at baseline would be associated with higher child BMI percentile and less healthful dietary intake one year later in unadjusted and adjusted models; (2) Parental media monitoring (TV rules, discussing content, coviewing) would be associated with reduced risk  and (3) moderate the effects TV exposure on child obesity and diet.   

Methods:  The study sample was drawn from the first two waves of STRONG Kids (n= 230), a prospective study of parent-child pairs in the Midwest. Parents (M= 33.5 years, SD= 6.3, 96% female) completed surveys, and child height and weight were measured at baseline (ages 2-4 years, M=3.1, SD=.59) and one year later. Independent variables at W1 included demographics, detailed measures of child TV exposures, and a standardized measure of three types of parental media monitoring (instructive, restrictive, and coviewing). Outcome variables at W2 included child BMI percentile and standardized items for reporting child dietary intake, categorized as healthful (fruit, vegetables) and unhealthful/obesogenic (sugar-sweetened beverages, French fries, fast food) based on prior literature. Multivariable OLS regressions were used and interaction terms were entered to assess moderators.  

Results: On average preschoolers viewed TV 74.4 minutes per weekday (SD= 63.6) and 125.4 minutes per weekend day (SD= 108.6). Families had an average of three TVs in the home and 56% of preschoolers had at least one TV in their bedroom; 12% had two. Many families (44%) watched TV during mealtimes. As posited, (1) more TV exposure in minutes/day was associated with child higher BMI percentile at W2 (r= 0.13, p< 0.05), fewer fruit/vegetable servings (r= -0.19, p= 0.002), and more combined servings of sugar-sweetened beverages, fast food, and French fries at W2 (r= 0.242, p< 0.001). In adjusted models, TV exposure at ages 2-4 predicted higher child BMI percentile at W2 (β= 0.143, p= .038), fewer fruit/vegetable servings (β= -0.186, p=0.005), and more daily combined servings of sugar-sweetened beverages, fast food, and French fries (β= 0.241, p< 0.001). (2) Parent media strategies did not predict lower obesity risk (3) nor buffer risk associations between TV exposure and obesity risk.   

Conclusions and Implications: Greater TV exposure in early childhood increases risk of obesity and unhealthful diet. Quantity is more important than quality: effects of TV time in early childhood were not buffered by parental TV rules, discussion, or coviewing strategies. The near ubiquity of household TV exposure among young children may undermine lifetime wellness and is an important Social Work topic for parent education and a serious public health concern.