UPDATE 7 JANUARY: For what Professor Carlsen actually said see:
Includes the comment from his press release: "So why do so many studies associate breastfeeding with better health for young babies. The answer is simple: If a mother is able to breastfeed, and does so, this ability is essentially proof that the baby has already had an optimal life inside the womb."
There is another round of articles suggesting that breastfeeding is not better for babies than infant formula. Yet looking at the details of the story, the above headline would be more relevant.
This latest round of articles is citing research from a Norwegian scientist, Sven Carlsen. Sensationalist journalists, such as one writing in the Daily Mail have declared: "Breast is NOT best... Women should forget what they have been told about the health benefits of breastfeeding..."
Read on, however, and you find that Prof. Carlsen does not disagree with the evidence regarding the benefits of breastfeeding.
Even the Daily Mail admits:
"Prof Carlsen's team reviewed data from more than 50 international studies looking at the relationship between breastfeeding and health. Most concluded that the more children were breastfed, the healthier they were. On the surface this was correct, said Prof Carlsen, from the Norwegian University of Science and Technology in Trondheim."
The hypothesis that Prof. Carlsen is proposing is that mothers reach for formula because they have excess male hormone. As the Daily Mail says later in its article:
The Norwegian scientists' own work pointed to links between levels of androgen male hormones in the wombs of pregnant women, the health of children, and breastfeeding.
'Pregnant women who have higher levels of androgens breastfeed less,' said Prof Carlsen. 'Probably this is a direct effect of hormones that simply limit nursing ability by reducing milk production in the breast.'
A pregnant woman's health affected hormones in her womb, which had knock-on effects on her unborn child, said the researchers.
Surely a more relevant headline would be: "Excess male hormone leads mothers to bottle feed and harms babies claims scientist".
We could perhaps question why the headline is not this, but "Breast is NOT best".
On past experience, some in discussion fora and email lists (possibly company trolls) will be seizing on the 'breast Not best' headline to shout down the evidence regarding breastfeeding. They too should be asked whey they are taking this line, rather than discussing the 'excess male hormones lead mothers to bottle feed' theory.
Rather than rushing to comment, however, I believe this whole story needs to be approached with a great deal more caution than that demonstrated by the Daily Mail and some other journalists.
Scientists who have conducted thousands of studies that have demonstrated that, taken as a population, formula-fed infant have poorer health outcomes than breastfed infants will no doubt claim that confounding variables have already been taken into account in their studies. Remember Pofessor Carlsen apparently admits that 'on the surface' these findings are correct - his claim is that it is not formula that has an adverse effect on babies, but supposed excess male hormone present in the mother during the pregnancy.
Whether there is any substance to this theory is something that will receive considered comment in the coming days. If there is any validity to this argument, how it has been possible to attribute 100% of the difference in health outcomes to male hormone rather than formula feeding needs to be scrutinised.
In the meantime some journalists run ahead with sensationalist headlines.
We faced a similar situation last year. You may recall the scientist, Professor Kramer, who was quoted in literally thousands of articles around the world came out and criticised the journalists who wrote the original article for misrepresenting what he had said - but few journalists and media outlets that had run the earlier articles issued follow-up corrections. See: