Adequate nighttime sleep has been shown in many studies to influence body weight in adults. But the same pattern may also be true for infants and toddlers. A study published Monday found that how much and, here's the key -- when -- babies sleep can be important to weight gain later in life.
Researchers from the University of Washington and UCLA used data from a national survey of children and adolescents to study 1,930 children ages 0 to 13. Information on the children was collected on two occasions, in 1997 and 2002.
The study showed that, by 2002, about one-third of the children were overweight or obese -- numbers that match many other national surveys conducted in recent years. As for the sleep-weight connection, the researchers found a strong link between duration of nighttime sleep among children ages 0 to 4 and subsequent obesity at ages 5 to 9 years. This association held up even when the researchers controlled for other factors that affect obesity, such as parents' body-mass index, family socioeconomic status and the hours the child watches television.
The link was true only among children ages 0 to 4, not in the older children.
"These findings suggest that there is a critical window prior to age 5 years when nighttime sleep may be important for subsequent obesity status," the authors wrote. The study is published in the Archives of Pediatric & Adolescent Medicine.