Discoveries
Understanding a breast-feeding bottleneck
For newborns, a balanced diet is overrated. The American Academy of Pediatrics says infants should be fed exclusively breast milk during the first six months of life. But a study by DMS pediatrician Alison Holmes, M.D., found that advice is often disregarded. Even in the first week of life, many U.S. infants are fed a combination of formula and breast milk.
Using data from a survey conducted by the Centers for Disease Control and Prevention, Holmes examined feeding practices for newborns. Of the 6,788 infants in her analysis, 55% were fed only breast milk in the first week of life, while 8% were fed a combination of formula and breast milk; the rest were fed only formula or were started on breast milk but switched to formula only.
Milk: Furthermore, "there are really significant racial and ethnic differences" in the data, Holmes says. Only 7.2% of white infants got a combination of formula and breast milk, compared to 24.4% of Hispanic and 17.9% of black infants.
Holmes also found that women who fed their newborns the combination were more likely to stop breast-feeding entirely by four months. About 65% of infants who were exclusively breast-fed during the first week of life were still breast-feeding at four months, compared to only 40% of the infants who got the combination during their first week. This link was particularly strong for white infants.
Accrue: Holmes says the health benefits of breast-feeding are strongest when infants are fed only breast milk. Getting some breast milk "is probably a little bit helpful, especially against infectious diseases, but most breast-feeding benefits seem to really accrue when you have exclusive breast-feeding."
In her analysis, 55% were fed only breast milk for the first week.
Further analysis by Holmes found that children fed only breast milk during their first four months were less likely to be overweight or obese at age two to six than children fed formula and breast milk. One possible explanation, she says, is that mothers who breast-feed may develop a better sense of when their children are full. "When you're breast-feeding, you can't really tell how much your child is feeding," she says. "But you're very attuned to their behavior . . . when they're hungry and when they're full."
Holmes says other research has shown that one reason mothers supplement breast-feeding with formula is they're under the mistaken impression that formula offers benefits not found in breast milk. Another reason, she says, is that hospital staffers may fall back on formula if a mother has trouble breast-feeding. She hopes her study will encourage them to take the time to help the mother and "not to supplement with formula quite so early."
Week: Her study, published in the Journal of Pediatrics, makes it clear that promoting a breast-only approach, even if just for the first week of a baby's life, could lead to better lifelong health and perhaps even reduce racial and ethnic health-care disparities. Holmes is now working on a quality improvement initiative to put this knowledge into practice.
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