Bottle feeding, even of breast milk, raises risk of rapid weight gain

A new study shows that infant weight gain may be associated with the way the milk is consumed, not only with the type of milk.

A study population of nearly 2,000 infants was followed from birth for 1 year using 10 maternal questionnaires about feeding practices. Mothers also reported infant weights on the 3-, 5-, 7-, and 12-month surveys.

Compared with infants fed only at the breast, infants fed only by bottle gained 71 g more per month when the bottles contained only nonhuman milk. When exclusively bottle-fed infants were given only human milk, they gained even more weight compared with breastfed infants-89 g more each month. Compared with infants fed at the breast, bottle-fed babies gained only 37 g more per month when fed both expressed human milk and nonhuman milk.

COMMENTARY

The researchers speculate that mothers feeding a baby at the breast may be able to better sense the baby's satiety. They also suggest that expressed breast milk given by bottle may be considered more precious than formula, leading the caregiver to continue attempting to feed the baby until the last drop is gone, perhaps explaining the more rapid weight gain in babies fed breast milk-rather than nonhuman milk-by bottle. -Michael Burke, MD