Breastfeeding - behind the headlines

A longitudinal study in Brazil was a hit with the media recently due to its findings on the positive impact of breastfeeding on cognition. The research prompted big headlines along with more sceptical coverage. But what was the real message, particularly for the quarter of mothers do not attempt to breastfeed?

The study, published in The Lancet, followed almost 3,500 babies from 1982, from a variety of socioeconomic backgrounds. In Brazil there is no social pattern for breastfeeding – mothers from all backgrounds are as likely to breastfeed as each other. The researchers – led by Professor Cesar Victora - found that compared to those who were breastfed for less than one month, those who were breastfed for 12 months or more had higher IQ, more years of education and higher monthly incomes.

If these results are correct, women who do not intend to breastfeed should perhaps be encouraged to try, not only due to the health benefits associated with breastfeeding but for the potential cognitive benefit and impact on life outcomes. So how can psychology help mothers through the (often demanding) process of breastfeeding, and were the conclusions drawn justified in any case?

Health Psychology researcher Ellinor Olander, Lecturer in Maternal and Child Health at City University London, said that breastfeeding education can have an effect on initiation of breastfeeding. She explained: ‘This evidence comes from a, now somewhat old, Cochrane review, and the education described includes formal and informal sessions, needs-based or one-to-one support.  It is also clear from health psychology literature that breastfeeding intention and attitude towards breastfeeding can also predict the actual behaviour shortly after birth.’

Dr Olander went on to say this leads to the question of why some women do not intend to initiate breastfeeding. ‘This seems to depend on who they are, for example the issue of embarrassment can be an important factor for why adolescent mothers do not intend to breastfeed, while research has shown for Bangladeshi women living in East London, cultural factors played an important role in breastfeeding initiation.’ Olander said occasionally things can happen which sway women away from initiating breastfeeding: ‘A recent example from Scotland is where obese women report that due to birth complications such as caesarean section they struggled with breastfeeding, commenting that they could not remember their first breastfeed,’ she said.

But what can health professionals do to encourage women to try to breastfeed? ‘I think we have to ensure all women intend to attempt breastfeeding,’ Olander said. ‘For this, midwives play a key role. They need to promote the advantages of breastfeeding, but also understand the women’s individual circumstances to provide woman-centred care, as well as show women how to breastfeed. That said, this assumes midwives and maternity support workers have time and feel they are able to care for women in a compassionate manner, which is not always the case, as evidenced by a very recent London study by Hunter, Magill-Cuerden and McCourt.’

Postdoctoral Fellow in Cognitive Ageing at the University of Edinburgh, Dr Stuart Ritchie, spoke about the study as a whole. He told us that intelligence was strongly heritable, and any study that attempts to look at parental effects on intelligence should control for this. He added: ‘To get around this problem, you can do one of two things; control for parental levels of intelligence, or compare siblings or twins within the same family to control for genetics. The authors of this study didn’t do either of these things in the paper, so we can’t know whether or not the apparent effect of breastfeeding on intelligence is just due to smarter parents tending to breastfeed more, for whatever reason.’ 

Ritchie pointed to other studies which have used the correct controls and found no effect of breastfeeding, or at most a very small one. He concluded: ‘There might be two arguments against my point above. First, the study does control for parental education, which we know is linked to parental intelligence. But the problem is we know they’re not exactly the same thing (and only correlate moderately). Second, there isn’t a socioeconomic gradient of breastfeeding in Brazil like there is in the US or the UK: that is, richer parents don’t tend to breastfeed any more or less. But again, parental socioeconomic status is only moderately correlated with parental intelligence, so without that crucial control for parental intelligence, we simply can’t draw any conclusions about whether breastfeeding has any effect.’

So, the jury is still out on whether breastfeeding has an effect on intelligence. As Dr Ritchie concluded: ‘with this study design, we can’t really know.’ And as psychologist Dean Burnett concluded in The Guardian, 'the research may have noble aims, interesting results and good intentions, but you can easily see how it would be spun out into more ways to fuel personal views and ideals. So at least bear that in mind when you see the coverage of it.'