San Diego, CA, December 11, 2012 - The average American child from age 8 to 18 watches about 4.5 hours of TV each day. Seventy percent have a TV in the bedroom and about one-third of youth aged 6-19 is considered obese. Previous studies have shown that TV viewing time during childhood and adolescence continues into adulthood, resulting in overweight and elevated total cholesterol. An investigative team from the Pennington Biomedical Research Center in Baton Rouge, LA reports new study findings, establishing the relationship between having and watching TV in the bedroom and childhood obesity, specifically high waist circumference.
"The established association between TV and obesity is predominantly based on BMI. The association between TV and fat mass, adiposity stored in specific depots (including abdominal subcutaneous and visceral adipose tissue), and cardiometabolic risk, is less well understood," says lead investigator Peter T. Katzmarzyk, PhD. "It is hypothesized that higher levels of TV viewing and the presence of a TV in the bedroom are associated with depot-specific adiposity and cardiometabolic risk."
Between 2010 and 2011, 369 children and adolescents aged 5-18 in Baton Rouge, representing a balance between gender, ethnicity, age, and BMI status, were evaluated for a variety of factors, such as waist circumference, resting blood pressure, fasting triglycerides, high-density lipoprotein cholesterol, and glucose, fat mass, and stomach fat.
Statistical analysis of the data developed produced two models. Together, these models revealed that children with a TV in the bedroom were more likely to watch more TV. These children also were shown to have more fat and subcutaneous adipose tissue mass, as well as higher waist circumference, when compared with their peers who did not have a bedroom TV. Study participants with a TV in the bedroom and those who watched TV more than two hours a day were each associated with up to 2.5 times the odds of the highest levels of fat mass. Viewing five or more hours a day produced an association of two times the odds of being in the top quartile for visceral adipose tissue mass. Further, a bedroom TV associated with three times the odds of elevated cardiometabolic risk, elevated waist circumference, and elevated triglycerides.
"There was a stronger association between having a TV in the bedroom versus TV viewing time, with the adiposity and health outcomes," notes study co-author Amanda Staiano, PhD. "A bedroom TV may create additional disruptions to healthy habits, above and beyond regular TV viewing. For instance, having a bedroom TV is related to lower amounts of sleep and lower prevalence of regular family meals, independent of total TV viewing time. Both short sleep duration and lack of regular family meals have been related to weight gain and obesity."