According to one of the most comprehensive studies ever undertaken, breastfeeding makes children smarter. Let's take a closer look

Breastfeeding boosts intelligence, according to one of the biggest studies ever undertaken. Over 14,000 children were tracked over six and a half years, and those who were breastfed did better in IQ tests. They were rated higher at reading, writing and in mathematics too.

“Our study provides the strongest evidence to date that prolonged and exclusive breastfeeding makes kids smarter,” said Professor Michael Kramer, from McGill University in Montreal. He added that he believes that the findings will help to “promote, protect and support” breastfeeding.

There have long been suggestions – and much research – looking into the issue of whether breastfeeding makes children more clever. This research – which was designed not to be influenced by outside factors such as the mother’s intelligence – appears to prove that it does.

The children followed in the research were born in 31 different hospitals in the Republic of Belarus, and the results reported in the journal Archives of General Psychiatry. At the age of six and a half, breastfed children scored 5.9 points higher on average in tests of overall intelligence and did similarly well or better in other, more specific IQ tests.

“The effect of breastfeeding on brain development and intelligence has long been a popular and hotly debated topic," said Prof Kramer.

"While most studies have been based on association, however, we can now make a causal inference between breastfeeding and intelligence - because of the randomised design of our study."

It is not entirely clear why breastfeeding causes these differences. It may be the existence of certain fatty acids or other substances contained in the breast milk, or it may simply be because of stronger interaction between mother and child. Breastfeeding also has other benefits, including a boost to children’s immunity.