Breastfeeding duration and weaning diet may shape child's body composition

May 28, 2009

Variations in both milk feeding and in the weaning diet are linked to differences in growth and development, and they have independent influences on body composition in early childhood, according to a new study accepted for publication in The Endocrine Society's Journal of Clinical Endocrinology & Metabolism (JCEM).

Previous studies suggest that the early environment may be a significant factor in childhood obesity. This study used dual x-ray absorptiometry to make direct measures of body composition in children at four years of age whose diets had been assessed when they were infants. The findings showed that children who had been breastfed longer had a lower fat mass which could not be explained by differences in family background or the child's height.

"Most studies linking infant feeding to later body composition focus on differences in milk feeding, but our study also considered the influence of the weaning diet," said Dr. Siân Robinson, PhD, of the MRC Epidemiology Resource Centre, University of Southampton in the United Kingdom and lead author of the study. "We found that, independent of the duration of breastfeeding, children with higher quality weaning diets including fruits, vegetables, and home-prepared foods had a greater lean mass at four years of age."

In this study, researchers assessed the diets of 536 children at six and 12 months of age. Diet was assessed using a food frequency questionnaire that was administered by trained research nurses to record the average frequency of consumption of specific foods. The age at which solid foods were introduced into the infant's diet was also recorded. In this study 'weaning' is defined as the period of transition in infancy between a diet based on milk feeding to one based on solid foods. The subjects' body composition was assessed at four years by dual X-ray absorptiometry.

"These findings are enlightening," said Professor Cyrus Cooper, Director of the MRC Epidemiology Resource Centre. "An influence of qualitative differences in the weaning diet on childhood body composition had not been described before."

More information: The article "Variations in infant feeding practice are associated with body composition in childhood: a prospective cohort study," will appear in the August 2009 issue of JCEM.

Source: The Endocrine Society (news : web)