TV time, physical activity, sleep duration associated with childhood BMI, body fat
Children who met Canadian guidelines for television viewing, physical activity and sleep duration were more likely to have less body fat and lower BMI compared with children who did not meet the guidelines, according to findings presented at the European Congress on Obesity.
“Overall, there is a low proportion of children that are meeting guidelines for sleep, physical activity and TV viewing,” Peter T. Katzmarzyk, PhD, of the Pennington Biomedical Research Center at Louisiana State University, told Endocrine Today. “However, those that meet all three guidelines had lower levels of overall body fat and also a much lower odds of being obese.”
Katzmarzyk and Amanda Staiano, PhD, assistant professor at the Pennington Biomedical Research Center, analyzed data from 375 white and black children aged 5 to 18 years recruited from the Baton Rouge area. The researchers measured height and weight and total fat mass via DXA; visceral and subcutaneous adipose tissue was measured via MRI. Physical activity, television viewing habits and sleep duration via questionnaires. Researchers compared data against the Canadian 24-hour movement guidelines, defined as follows:
- At least 60 minutes per day of moderate to vigorous physical activity 5 days per week;
- 2 hours or less of television viewing time;
- Sleeping between 9 and 11 hours per night for children aged 5 to 13 years, and 8 to 10 hours per night for children aged 14 to 18 years.
Within the cohort, researchers found that 35% of children met guidelines for moderate to vigorous physical activity, 31% met guidelines for television viewing and 52% met goals for sleep duration, whereas 27% of children met none of the guidelines, 36% met one of the guidelines, 28% met two of the guidelines and 8% met all three guidelines. A higher proportion of white children met the guidelines vs. black children, researchers noted.
Odds for developing obesity increased when children achieved fewer parameters, according to the researchers. When compared with children who met none of the guidelines, those who met all three parameters had 89% lower odds of having obesity (OR = 0.12; 95% CI, 0.03-0.56). In children meeting two of three guidelines, the OR was 0.7 (95% CI, 0.38-1.29) vs. those meeting none of the guidelines. In children who met only one of the guidelines, OR for developing obesity was 0.79 (95% CI, 0.46-1.35) vs. children meeting none of the guidelines.
In addition, meeting the guideline for moderate to vigorous physical asctivity was associated with having lower total fat mass and subcutaneous adipose tissue, whereas meeting the television viewing guideline was associated with lower BMI, total fat mass and subcutaneous adipose tissue mass. Meeting the sleep guideline was associated with lower BMI, total fat mass, subcutaneous adipose tissue mass and visceral adipose tissue mass.
“It may be prudent for physicians to focus on addressing an overall healthy lifestyle with pediatric patients that includes reductions in TV viewing and increasing physical activity and sleep duration,” Katzmarzyk said. “This has the potential to be more effective than focusing on a single lifestyle behavior.”
Katzmarzyk added that researchers should focus on interventions that test whether addressing multiple behaviors results in greater weight and fat loss compared with interventions that address only a single behavior. – by Regina Schaffer
Katzmarzyk P, Staiano A. Poster T4P107. European Congress on Obesity; May 17-20, 2017; Porto, Portugal.
Disclosure: The researchers report no relevant financial disclosures.