There is an increased risk that a child will be overweight in preschool if, in infancy, he or she sleeps less than 12 hours per day, according to a report in the April 2008 issue of the Archives of Pediatrics & Adolescent Medicine, a JAMA journal.
Between the ages of two and five years, approximately one fourth of children are overweight or at risk for being overweight. Studies performed on adults, adolescents, and older children in the past have indicated that sleep restriction changes hormone levels, which could stimulate hunger and increase weight gain.
To study this relationship in infants, Elsie M. Taveras, M.D., M.P.H., of Harvard Medical School and Harvard Pilgrim Health Care, Boston, and colleagues investigated 915 children whose mothers visited a single group practice in eastern Massachusetts for their prenatal health care. These children were weighed and measured immediately after birth, again at the age of six months, and three years after that. Mothers gave details on their children’s sleep habits during these follow up visits, as well as in questionnaires one and two years after birth. Using these reports, the investigators calculated the daily duration of sleep for each child between the ages of six months and two years.
The infants as a group slept an average of 12.3 hours per day. At the age of three, 9% of the children in the study (83) were overweight. After adjusting for other factors that influence a child’s weight, such as the body mass index of the mother before pregnancy, the infants who slept less than 12 hours per day had a higher body mass index for their age and sex, a higher skinfold thickness, and were more likely to be overweight at the age of three.
The investigators also perused the influence of television viewing on the association between sleep and being overweight, and it was found that this association was minimal. But, when little sleep and increased television time were combined, the highest risk of being overweight was found. The authors explain: “Our findings lend support to childhood overweight prevention interventions that target both reduction in television viewing and ensuring adequate sleep duration.”
They also indicate that it is not completely understood what precise association sleep has with being overweight. “The mechanisms underlying the association between sleep duration and adiposity [amount of body fat] are unclear,” write the authors. They postulate that in addition to altered hormone levels, sleeping at night might cause daytime sleepiness and lower levels of activity during waking hours. Also, spending more time awake could simply offer more opportunities to eat.
They indicate that these results could help parents use methods that will improve infants’ quality of sleep. “Strategies to improve sleep duration among young children may be an important component of behavioral interventions that promote childhood overweight prevention,” they state. “Our findings suggest that clinicians and parents may wish to use evidence-based sleep hygiene techniques to improve sleep quality and perhaps increase sleep duration.”
Short Sleep Duration in Infancy and Risk of Childhood Overweight
Elsie M. Taveras; Sheryl L. Rifas-Shiman; Emily Oken; Erica P. Gunderson; Matthew W. Gillman
Arch Pediatr Adolesc Med. 2008;162(4):305-311.
Written by Anna Sophia McKenney