News article

Breastfeeding and Asthma

September 27, 2002

A study by Malcolm Sears and others, recently published in the September 21, 2002 issue of the British medical journal, The Lancet concluded that “breastfeeding does not protect children against atopy [allergic diseases] and asthma and may even increase the risk.” The Massachusetts Breastfeeding Coalition has reviewed this study and finds it to be flawed, because the study states that “many newborns who were breastfed received a nightly formula feed while in hospital to allow the mother to sleep.”

There have been numerous studies showing a reduction in asthma in children who were exclusively breastfed, that is, they did not receive any formula at all. This suggests that early exposure to formula may increase the risk of asthma. For example, recent study by Wendy Oddy and others, out of Australia, studied twice as many children as The Lancet study, and found a significant reduction in the risk of asthma in 6 year old children who were exclusively breastfed. (see the Public Health section of our website for references).

An unspecified, significant number of the children in The Lancet study were not exclusively breastfed - and in fact received formula in the early newborn period when their immune systems were the most vulnerable and immature, and when their guts were most permeable. Even one bottle of supplemental formula has been shown to alter the pH of the gut. Two bottles may be all it takes to sensitize an already allergy-prone baby. As with the relationship between breastfeeding and other diseases, it is clear that exclusive breastfeeding should be the reference standard.

The Massachusetts Breastfeeding Coalition believes the study in The Lancet by Malcolm Sears and others does not contradict the numerous earlier studies in which exclusive breastfeeding is linked to significant reductions in the risk of asthma in later life.