Effects of prolonged and exclusive breastfeeding on child height, weight, adiposity, and blood pressure at age 6.5 y: evidence from a large randomized trial

Abstract

Background:The evidence that breastfeeding protects against obesity and a variety of chronic diseases comes almost entirely from observational studies, which have a potential for bias due to confounding, selection bias, and selective publication. Objective: We assessed whether an intervention designed to promote exclusive and prolonged breastfeeding affects children's height, weight, adiposity, and blood pressure at age 6.5 y. Design: The Promotion of Breastfeeding Intervention Trial (PROBIT) is a cluster-randomized trial of a breastfeeding promotion intervention based on the WHO/UNICEF Baby-Friendly Hospital Initiative. A total of 17 046 healthy breastfed infants were enrolled from 31 Belarussian maternity hospitals and their affiliated clinics; of those infants, 13 889 (81.5%) were followed up at 6.5 y with duplicate measurements of anthropometric variables and blood pressure. Analysis was based on intention to treat, with statistical adjustment for clustering within hospitals or clinics to permit inferences at the individual level.

Delayed introduction of solid feeding reduces child overweight and obesity at 10 years

“…The duration of exclusive or any breastfeeding was not independently associated with above healthy BMI at age 10 years. This supports the lack of association between breastfeeding and child overweight found by a recent large randomized trial, 9 and suggests that the function performed by the timing of introduction of solid foods in the development of child obesity requires greater attention.…”

“…6 Reviews have found that crude associations between breastfeeding and reduced child obesity were significantly attenuated by adjustment for potential confounders. 7,8 A recent large randomized trial found increased duration and exclusivity of breastfeeding was not associated with reduced adiposity measures at age 6.5 years, 9 suggesting that earlier published associations may be explained by residual confounding. One such unmeasured confounder may be the timing of introduction of solid foods, which has been less extensively studied in relation to child obesity than breastfeeding, [10][11][12][13] and has not yet been synthesized into a published review.…”

Early feeding practices and family structure: associations with overweight in children

“…Some studies have found a positive, dose-dependent association between breastfeeding and weight status (11)(12)(13) , while others have reported a nonlinear positive response (14)(15)(16) . On the contrary, other studies have demonstrated little or no protective association between breastfeeding and overweight; including a longitudinal study of infant feeding and obesity which found that exclusive breastfeeding was not related to being overweight or obese during adult life (17)(18)(19)(20)(21) . Similarly, a systematic analysis conducted by the WHO (22) and a systematic review of the literature found that after adjustment for maternal overweight the effect of breastfeeding was eliminated (23) .…”

Can Breastfeeding Reduce the Risk of Childhood Obesity?

“…For children followed up at 6.5 years, there were no significant differences in mean BMI (i.e., 15.6kg/m 2 in both arms of the trial) or in the prevalence of overweight; OR 1.1(95%CI 0.8-1.4) or obesity; OR 1.2 (95%CI 0.8-1.6) between the two groups. (Kramer et al, 2007). The authors concluded that the PROBIT trial did not provide conclusive evidence for or against a potential effect of breastfeeding on body composition.…”

“…The final section in this chapter will summarize the systematic reviews and meta-analyses on breastfeeding and obesity conducted over the last 10 years and provide some thoughts on future research. The protective effect of breastfeeding against childhood obesity was initially proposed by Kramer in 1981(Kramer, 1981 and since then numerous studies have been conducted in order to examine the relationship between breastfeeding and childhood overweight and obesity (Twells & Newhook, 2010;Bergmann et al, 2003;Hediger et al, 2001, Buyken et al, 2008Dewey, 1998;Kramer et al, 2007;Metzger & McDade, 2010;Savino et al, 2009;Singhal & Lanigan, 2007;Victora et al, 1998;Araujo et al, 2006;Burdette et al, 2006;GummerStrawn & Mei, 2004). More recently, a number of systematic reviews and meta-analyses on this topic have been conducted (Arenz et al, 2004;Harder et al, 2005;, Horta et al, 2007.…”