US researchers at the Geisel School of Medicine at Dartmouth conducted a telephone survey in 2003 of 6,522 boys and girls (ages 10 to 14 years) to ask about bedroom televisions. Body mass index (BMI) at two and four years after baseline was based on self-report and parent-reported weight and height for their children.
More than one-third of children and adolescents in the US are overweight or obese, and it is estimated that 71 per cent of children and adolescents (ages 8 to 18 years) have televisions in their bedrooms, according to background information in the article.
At baseline, 59.1 per cent of the children surveyed reported having a bedroom television. More boys, ethnic minorities and children of lower socioeconomic status reported having bedroom televisions. It was found that having a bedroom television was associated with an excess BMI of 0.57 at two years and 0.75 at four years of follow-up, and a BMI gain of 0.24 between years two and four.
The authors speculated the association could possibly be due to disrupted sleep patterns or greater exposure to child-targeted food advertising, although this study did not investigate causal reasons.
“This work underscores the need for interventional studies to explore whether removing televisions from child bedrooms results in lower adiposity (fat) gain.”
JAMA Pediatr. Published online March 3, 2014. doi:10.1001/jamapediatrics.2013.3921