Effects of Promoting Longer-term and Exclusive Breastfeeding on Adiposity and Insulin-like Growth Factor-I at Age 11.5 Years

Abstract

Importance Evidence that longer-term and exclusive breastfeeding reduces child obesity risk is based on observational studies that are prone to confounding.Objective To investigate effects of an intervention to promote increased duration and exclusivity of breastfeeding on child adiposity and circulating insulin-like growth factor (IGF)-I, which regulates growth.Design, Setting, and Participants Cluster-randomized controlled trial in 31 Belarusian maternity hospitals and their affiliated clinics, randomized into 1 of 2 groups: breastfeeding promotion intervention (n=16) or usual practices (n=15). Participants were 17 046 breastfeeding mother-infant pairs enrolled in 1996 and 1997, of whom 13 879 (81.4%) were followed up between January 2008 and December 2010 at a median age of 11.5 years.Intervention Breastfeeding promotion intervention modeled on the WHO/ UNICEF Baby-Friendly Hospital Initiative (World Health Organization/United Nations Children's Fund).Main Outcome Measures Body mass index (BMI), fat and fat-free mass indices (FMI and FFMI), percent body fat, waist circumference, triceps and subscapular skinfold thicknesses, overweight and obesity, and whole-blood IGF-I. Primary analysis was based on modified intention-to-treat (without imputation), accounting for clustering within hospitals and clinics. ResultsThe experimental intervention substantially increased breastfeeding duration and exclusivity when compared with the control (43% vs 6% exclusively breastfed at 3 months and 7.9% vs 0.6% at 6 months). Cluster-adjusted mean differences in outcomes at 11.5 years of age between experimental vs control groups were: 0.19 (95% CI, Ϫ0.09 to 0.46) for BMI; 0.12 (Ϫ0.03 to 0.28) for FMI; 0.04 (Ϫ0.11 to 0.18) for FFMI; 0.47% (Ϫ0.11% to 1.05%) for percent body fat; 0.30 cm (Ϫ1.41 to 2.01) for waist circumference; Ϫ0.07 mm (Ϫ1.71 to 1.57) for triceps and Ϫ0.02 mm (Ϫ0.79 to 0.75) for subscapular skinfold thicknesses; and Ϫ0.02 standard deviations (Ϫ0.12 to 0.08) for IGF-I. The cluster-adjusted odds ratio for overweight/obesity (BMI Ն85th vs Ͻ85th percentile) was 1.18 (95% CI, 1.01 to 1.39) and for obesity (BMI Ն95th vs Ͻ85th percentile) was 1.17 (95% CI, 0.97 to 1.41). Conclusions and RelevanceAmong healthy term infants in Belarus, an intervention that succeeded in improving the duration and exclusivity of breastfeeding did not prevent overweight or obesity, nor did it affect IGF-I levels at age 11.5 years. Breastfeeding has many advantages but population strategies to increase the duration and exclusivity of breastfeeding are unlikely to curb the obesity epidemic.

Latent protective effects of breastfeeding on late childhood overweight and obesity: A nationwide prospective study

“…The latent effects of breastfeeding may explain the inconsistency in previous results on the association between BMI and breastfeeding (13,23,24). In previous studies, the children's ages ranged predominantly from 3 to 6 years (7,(24)(25)(26) or the children were over 9 years old (6,12). In our study, a significant slower increase of BMI with age was observed in both boys and girls in late childhood, that is, after 7 years in boys and at 8 years in girls, who were breastfed compared with those who were formula-fed.…”

Food Parenting: A Selective Review of Current Measurement and an Empirical Examination To Inform Future Measurement

“…15,16 However, research on breastfeeding and overweight has demonstrated mixed results. 17,18 A World Health Organization review in 2007 supported the link, 18 whereas others [19][20][21] found no association between duration of breastfeeding and adulthood overweight. Research findings are also mixed on the outcomes of early or late introduction of complementary foods.…”

DOHaD

“…De nombreuses études se sont par la suite intéressées aux relations entre le mode d'allaitement et le risque d'obésité à long terme, et concluaient, en général, à un effet protecteur faible de l'allaitement maternel [30] avec des résultats parfois contradictoires [31]. Le seul essai randomisé permettant d'évaluer les effets à long terme de la promotion de l'allaitement maternel en maternité, n'a pas montré d'effet sur le risque de surpoids de l'enfant lorsqu'il atteint ses 11 ans [32]. Outre des facteurs de confusion qui n'ont pas toujours pu être pris en compte de façon similaire dans les différentes études, les caractéristiques de l'alimentation des enfants non allaités par leur mère, qui servent de comparateur dans les études observationnelles, participent à la variabilité des résultats de ces travaux.…”