Infants and toddlers who sleep less than 12 hours a day are twice as likely to become overweight by age 3 than children who sleep longer. In addition, high levels of television viewing combined with less sleep elevates the risk, so that children who sleep less than 12 hours and who view two or more hours of television per day have a 16 percent chance of becoming overweight by age 3.

“Mounting research suggests that decreased sleep time may be more hazardous to our health than we imagined,” says Elsie Taveras, MD, assistant professor in Harvard Medical School’s Department of Ambulatory Care and Prevention and lead author on the study. “We are now learning that those hazardous effects are true even for young infants.”

Results are published in the April 2008 issue of Archives of Pediatric and Adolescent Medicine.

The study team identified 915 mother-infant pairs from Project Viva, a long-term study of the effects of diet and other lifestyle factors on maternal and child health over time.

Infant weight and measurements were taken at several in-person visits up to three years of age. Mothers reported how many hours their child slept per day on average at 6 months, 1 year, and 2 years postpartum. Parents were also asked to report the average number of hours their children watched television on weekdays and weekends.

The combination of low levels of sleep and high levels of television viewing appeared to be synergistic and was associated with markedly higher BMI scores and increased odds of becoming overweight.

“Although previous studies have shown a similar link between sleep restriction and overweight in older children, adolescents, and adults, this the first study to examine the connection in very young children,” says Matthew Gillman, MD, SM, Harvard Medical School associate professor and director of the Obesity Prevention Program in the Department of Ambulatory Care and Prevention. Gillman is also the study’s senior author.

Television viewing is also a known risk factor for children becoming overweight.

These study results support efforts to reduce television viewing and to promote adequate sleep in efforts to prevent and reduce unhealthy childhood weight-gain. Children who are overweight are often at higher risk for obesity and related conditions, such as hyperlipidemia, hypertension, asthma, and type II diabetes, later in life.

“Getting enough sleep is becoming more and more difficult with TV, Internet, and video games in the rooms where children sleep,” says Dr. Taveras. “Our findings suggest that parents may wish to employ proven sleep hygiene techniques, such as removing TV from children’s bedrooms, to improve sleep quality and perhaps sleep duration.”

This study was supported by the National Institutes of Health, the Harold Amos Medical Faculty Development Program, and the Robert Wood Johnson Foundation.

Full citation:

Archives of Pediatric and Adolescent Medicine, Vol. 162, 4

“Short Sleep Duration in Infancy and Risk of Childhood Overweight”

Elsie M. Taveras, MD, MPH(1), Sheryl L. Rifas-Shiman, MPH(1), Emily Oken, MD, MPH(1), Erica P. Gunderson, Ph.D.(2), and Matthew W. Gillman MD, SM (1,3)

1) Obesity Prevention Program and Center for Child Health Care Studies, Department of Ambulatory Care and Prevention, Harvard Medical School and Harvard Pilgrim Health Care, Boston, MA; 2) Kaiser Permanente, Division of Research, Oakland, CA; and 3) Department of Nutrition, Harvard School of Public Health, Boston, MA.

Harvard Medical School has more than 7,500 full-time faculty working in 11 academic departments located at the School’s Boston campus or in one of 47 hospital-based clinical departments at 18 Harvard-affiliated teaching hospitals and research institutes. Those affiliates include Beth Israel Deaconess Medical Center, Brigham and Women’s Hospital, Cambridge Health Alliance, Children’s Hospital Boston, Dana-Farber Cancer Institute, Forsyth Institute, Harvard Pilgrim Health Care, Hebrew SeniorLife, Joslin Diabetes Center, Judge Baker Children’s Center, Immune Disease Institute, Massachusetts Eye and Ear Infirmary, Massachusetts General Hospital, McLean Hospital, Mount Auburn Hospital, Schepens Eye Research Institute, Spaulding Rehabilitation Hospital, and VA Boston Healthcare System.

FINDINGS
Infants and toddlers who sleep less than 12 hours a day and who watch two or more hours of television per day are twice as likely to become overweight by age 3 than children who sleep longer.

RELEVANCE
This is the first study to investigate the link between sleep and overweight in very young children.

INVESTIGATORS
Elsie Taveras, MD, Assistant Professor in the Department of Ambulatory Care and Prevention, Harvard Medical School

Source: Harvard Medical School

CITATION
Archives of Pediatric and Adolescent Medicine, April 2008