Clinical Question

Is the size of the bottle used to feed infants associated with weight gain?

Bottom Line

In nonbreastfed infants, using large bottles (at least 6 oz [180 mL]) to feed infants two months of age was associated with greater weight gain by six months of age. The authors did not report adverse effects associated with bottle size. This is an interesting study that suggests that smaller bottles may prevent overfeeding. (Level of Evidence = 2b)

Synopsis

The data for this study were obtained from a study aimed at preventing childhood obesity. The U.S. authors identified 386 infants who were born at least 34 weeks' gestational age, weighed at least 1,500 g (3 lb, 5 oz), and were exclusively formula-fed. The infant population was 41% black, 35% Hispanic, and 23% white. At the two-month visit, parents of 44% of the infants reported using large (at least 6 oz) bottles. White parents and parents of boys were more likely to use larger bottles. All infants were examined again at six months. After adjustment for birth weight, time between visits, and other variables, infants fed with large bottles had 0.21 kg (95% confidence interval, 0.05 to 0.37) more weight change at the six-month visit. The study did not randomly assign bottle sizes to children, and the authors did not report on children older than six months, although other studies have shown that weight gain between two and four months of age predicts the likelihood of being overweight at two years of age. This is a preliminary study that suggests that using smaller bottles at an early age might prevent overfeeding.

Study design: Cohort (prospective)

Funding source: Government

Setting: Outpatient (primary care)

Reference: WoodCTSkinnerACYinHSet alBottle size and weight gain in formula-fed infants. Pediatrics2016;138(1):e20154538.