Plenty of studies connect poor sleep habits in adults to obesity, but few track the long term effect of infants’ sleep throughout childhood. That's why Dr. Elsie Taveras, chief of general pediatrics at Massachusetts General Hospital for Children, and her colleagues followed babies every year from 6 months old until they were 7. At each visit, the team recorded height, weight, body fat, waist and hip circumference and sleep habit information to get the most complete picture yet of how sleep patterns are connected to childhood health.
Taveras rated the children’s sleep according to the recommended amounts for their age group set by the National Sleep Foundation and the National Heart, Lung and Blood Institute—for those under 2, that was more than 12 hours a day; for 3-4 year olds, that was more than 10 hours a day; and for kids 5 to 7, that was more than nine hours daily. At age 7, children with the lowest sleep scores throughout their young lives had the highest rates of obesity and body fat, specifically abdominal fat which other studies have linked to a higher risk of chronic conditions such as heart disease and diabetes.
What sets Taveras’ work apart is that it shows how consistently disrupted sleep throughout childhood can have a cumulative effect on health. “This lends more evidence to the fact that insufficient sleep has significant health implications,” she says.
Consistently skimping on shut-eye, especially at an early age, may interfere with appetite hormones that control how hungry and full we feel. And because sleep is an important time for the body’s metabolism to reset itself, sleep deprivation can also skew the body’s circadian clock, changing the body’s ability to burn calories from the diet and leading to higher blood sugar levels.
The findings strengthen what’s known about the importance of sleep in keeping the body’s metabolism running smoothly, but for the youngest children, it also highlights the critical role that parents play in establishing healthy sleep habits. “Household routines, such as bed times and meal times, can be important for getting enough sleep,” says Taveras. “I usually say three things to parents who are worried about their children’s sleep—implement consistent routines around bed times and meal times; reduce the amount of caffeinated beverages they drink during the day; and eliminate high tech distractions from their bedrooms.”