Breastfeeding is a good thing. I heartily endorse it; I did it with four children; I really enjoyed it.
But it isn’t nearly as good as lactivists have implied. For example, all those long term health benefits of breastfeeding that you’ve heard about? None of them exist.
Don’t believe me? Perhaps you will believe the World Health Organization.
The World Health Organization recently published Long-term effects of breastfeeding; a systematic review by Horta and Victora. It is a 74 page paper, but it can be summed up in one sentence:
There is no evidence for any long term health benefits of breastfeeding.
The paper is an evaluation of the entire world literature on the long term benefits of breastfeeding and it is divided into individual sections for each purported benefit. These include overweight and obesity, blood pressure, serum cholesterol, type-2 diabetes, and intellectual performance.
In every case, the scientific literature does not support a claim of benefit.
Specifically:
1. Overweight and obesity
Our conclusion is that the meta-analysis of higher-quality studies suggests a small reduction, of about 10%, in the prevalence of overweight or obesity in children exposed to longer durations of breast-feeding. Nevertheless, it is not possible to completely rule out residual confounding because in most study settings breastfeeding duration was higher in families where the parents were more educated and had higher income levels.
In other words, the observed effect is very small and probably due entirely to confounding.
2. Blood pressure
[The] findings are consistent with a small protective effect of breastfeeding against systolic bloodpressure, but residual confounding cannot be ruled out.
Once again, the observed effect is small and probably due entirely to confounding.
3. Cholesterol
Because the confidence interval included the null effect, these results do not support a long-term programming effect of breastfeeding on blood lipids.
4. Type-2 diabetes
The evidence suggests that breastfeeding may have a protective effect against type-2 diabetes,particularly among adolescents. Obesity/overweight seems to account for part of the association. Generalization from these findings is restricted by the small number of studies and the presence of significant heterogeneity among them.
5. IQ
[A]mong those studies that adjusted for maternal intelligence, breastfeeding was associated with an additional 2.19 IQ points… [T]he practical implications of a small increase in the performance in intelligence tests may be open to debate.
Since IQ tests are generally acknowledged to have a standard error of 3 points, there is no difference.
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These results are not news. The new study merely confirms the results from the original WHO study of the same name published in 2007.
These results are not surprising. With the exception of IQ testing, the studied outcomes are risk factors for diseases of adulthood and old age.Throughout most of human existence, life span was approximately 35 years, and diseases of old age had little to no impact on the survival of the species. There is no reason to expect there would be much of an evolutionary advantage to avoiding the disease of old age.
In industrialized societies, the benefits of breastfeeding are small and short term. That’s why there is no reason for any mother who chooses bottlefeeding to feel guilty. Breast milk is not “liquid gold.” It’s just milk and confers a few small, short term benefits across populations compared to infant formula.
