April 6, 2023

expert reaction to breast and mixed-fed babies (versus formula-fed babies) and risk of having special educational needs

A study published in PLOS Medicine looks at infant feeding method and special educational need in Scottish school children.

Dr Danya Glaser, Visiting Professor, UCL, and honorary consultant child & adolescent psychiatrist at Great Ormond Street Hospital for Children, said:

“Correlations are not causal.  There could be factors other than no breast feeding which are associated with special educational needs, such as low socio-economic status.  There is also a correlation between no breast feeding and low socio-economic status.  This study has not adequately controlled for this.”

Prof Ken Ong, Medical Research Council Epidemiology Unit & Department of Paediatrics, University of Cambridge, said:

“Strengths of this study are the large number of children from across Scotland with good quality data on breastfeeding at six weeks and educational outcomes, particularly more severe educational categories.

“A major limitation is the lack of data on parents’ education.  We know that better educated parents are more likely to breastfeed their children and it is important to take this into account before we can assume a causal effect of breastfeeding on preventing special educational needs and learning difficulties.

“Another limitation is they had information on breastfeeding only at age six weeks, and it would have been helpful to know if there is an optimal duration of breastfeeding or whether ‘the longer the better’.”

Prof Petroc Sumner, Head of School of Psychology, Cardiff University, said:

“This is a large and useful study which is all too easy to interpret as showing breast-feeding helps protect a child from risk.  But we must always be careful when reading cause into correlations.  Most importantly, the authors note that the data did not allow them to control for parental education level, which is one of the plausible reasons why an association between infant feeding method and educational needs might exist.”

Dr David Hill, MRC Research Fellow, Lothian Birth Cohorts, Department of Psychology, University of Edinburgh, said:

“As the authors note in their paper, they had no data on parental health, education, or IQ.  This does place some severe limitations on the claim that breastfeeding in infancy could be a modifiable risk factor for the causes of special educational need.

“For example, women with a higher IQ are more likely to breastfeed and are more likely to have a higher level of education and be in better physical health, than women with a lower IQ.  As such, by measuring the effect of breastfeeding on special educational needs, the authors are also measuring if the physical health, socioeconomic status, and the IQ of mother is associated with the special educational needs of their children.  In addition, parents share genes with their children.  Children born to mothers with a higher IQ are likely to have inherited genetic variants that leave them less likely to have special educational needs.”

‘Infant feeding method and special educational need in 191,745 Scottish schoolchildren: a national, retrospective cohort study’ by Lisa J Adams et al. was published in PLOS Medicine at 19:00 UK time on Thursday 6 April 2023.

Declared interests

Dr Danya Glaser: “None.”

Prof Ken Ong: “I have no conflicts to declare.”

Prof Petroc Sumner: “No conflicts.”

Dr David Hill: “I have no competing interests.”