Chronic insufficient sleep may increase obesity and overall body fat in children, according to a recent study.

In one of the most compelling studies of the potential link between reduced sleep and childhood obesity, researchers from the Massachusetts General Hospital for Children found that children who consistently received less than the recommended hours of sleep during infancy and early childhood had increases in both obesity and in adiposity or overall body fat by age 7.

"Our study found convincing evidence that getting less than recommended amounts of sleep across early childhood is an independent and strong risk factor for obesity and adiposity," Elsie Taveras, lead author of the study and chief of General Pediatrics at MGHfC. "Contrary to some published studies, we did not find a particular 'critical period' for the influence of sleep duration on weight gain. Instead, insufficient sleep at any time in early childhood had adverse effects."

For the study, researchers analyzed data from Project Viva, a long-term investigation of the health impacts of several factors during pregnancy and after birth. Information used in this study was gathered from mothers at in-person interviews when their children were around 6 months, 3 years and 7 years old, and from questionnaires completed when the children were ages 1, 2, 4, 5 and 6.

They found that children with the lowest sleep scores had the highest levels of all body measurements reflecting obesity and adiposity, including abdominal fat which is considered to be particularly hazardous. The association was consistent at all ages, indicting there was no critical period for the interaction between sleep and weight. Lower sleep scores were more common in homes with lower incomes, less maternal education and among racial and ethnic minorities; but the association between sleep and obesity/adiposity was not changed by adjusting for those and other factors.

While we need more trials to determine if improving sleep leads to reduced obesity, right now we can recommend that clinicians teach young patients and their parents ways to get a better night's sleep - including setting a consistent bedtime, limiting caffeinated beverages late in the day and cutting out high-tech distractions in the bedroom," Taveras said. "All of these help promote good sleep habits, which also may boost alertness for school or work, improve mood and enhance the overall quality of life."

The findings were recently published in Pediatrics.