A recent Scottish study shows that breast-fed babies are at reduced risk of developing childhood obesity.
Julie Armstrong, John Reilly and colleagues studied 52 394 Scottish children aged 39–42 months, 25% of whom had been fed only breast milk as infants and 7% breast milk and formula. After adjusting for socioeconomic status, birth weight and sex, the children who were breast-fed had a significantly lower prevalence of obesity compared with children who were fed formula.
“The magnitude of risk reduction [approximately 30%] is modest and is consistent with other work in this area,” states Reilly. “A previous study in the United States concluded that, at this level of risk, approximately 10% of cases of adult obesity could be attributed to formula feeding.”
While there is proof that breast-feeding is beneficial in reducing obesity, the authors say it is still unclear why. “Breast-fed infants have a good deal of control over the feeding process, but in formula-fed babies control is removed and this may lead to impaired ability to regulate food intake,” says Reilly. “[Also,] a number of endocrine/metabolic differences have been described between breast and formula feeders, suggesting that development of fat cells is more tightly controlled in the breast-fed baby.”
The study (Lancet 2002;359:2003-4) presents evidence that breast-feeding could be useful in population-based strategies aimed at preventing childhood obesity, and it gives a further boost to child health practitioners who wish to promote the beneficial effects of breast-feeding. — Cathel Kerr, Fife, Scotland
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