Child care factors associated with weight gain in infancy

Nine-month-old infants regularly cared for by someone other than a parent appear to have higher rates of unfavorable feeding practices and to weigh more than infants cared for only by parents, according to a report in the July issue of Archives of Pediatrics & Adolescent Medicine, one of the JAMA/Archives journals.

Almost three-fourths of infants receive some form of child care by persons who are not their parents during the first year of life, according to background information in the article. Child care has been associated with positive development in cognition (thinking, learning and memory), language, social and emotional realms and academics, the authors note. However, no information previously existed regarding the relationship of child care to infants' weight or to certain feeding practices that may affect the risk of becoming overweight, including breastfeeding and introducing solid foods at an earlier age.

Juhee Kim., Sc.D., of the University of Illinois at Urbana-Champaign, and Karen E. Peterson, Sc.D., of the Harvard School of Public Health, Boston, analyzed data collected during home visits with 8,150 9-month-old infants. During the visits, which occurred in 2001 and 2002, the infants were weighed and measured and the primary caregiver provided information regarding child care.

A total of 55.3 percent of the infants received regular child care from someone other than a parent. Among those, half were in full-time child care, 40.3 percent began child care at younger than 3 months, 39.3 percent began between 3 and 5.9 months and 20.7 percent began at 6 months or older.

"Infants who initiated child care at younger than 3 months were less likely to have been breastfed and were more likely to have received early introduction of solid foods than those in parental care," the authors write. Infants in part-time child care gained 175 grams (approximately 0.4 pounds) more weight during nine months than infants who were cared for by parents. Those who were cared for by other relatives gained 162 grams (approximately 0.35 pounds) more weight, had a higher rate of early introduction to solid foods (which was shown to be a risk factor for weight gain) and were less likely to begin breastfeeding.

"Our study results provide new evidence that child care influences both infant feeding practices and risk of overweight at least during infancy," the authors conclude. "Thus, more research is needed to understand the mechanisms by which these early child care factors and infant feeding practices affect subsequent risk for childhood overweight."

(Arch Pediatr Adoles Med. 2008;162[7]:627-633. Available pre-embargo to the media at www.jamamedia.org.)

Editor's Note: This study was supported in part by the Berkowitz Fellowship of the Department of Nutrition, Harvard School of Public Health, an ECLS-B cohort training grant, the National Center for Education Statistics and Training Grants on Statistical Analysis for Education Policy from the American Educational Research Association. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.