A long-term study has indicated an association between breastfeeding and intelligence. The research was done in Brazil, where the researchers traced around 3,500 babies, from all walks of life, and found that those who had been breastfed for longer went on to score higher on IQ tests as adults.

The experts have said that the results, while not convincing, have appeared to back current advice that babies should be completely breastfed for six months. But still, they mentioned that the mothers should have a choice about whether or not to do it.

The findings, published in The Lancet Global Health, have stressed that there are a number of different factors other than breastfeeding that could have an impact on intelligence. The researchers tried to rule out the major confounders, such as mother's education, family income and birth weight.

Dr. Bernardo Lessa Horta, from the Federal University of Pelotas in Brazil, said that the study led by him has offered a unique insight, as in the population he observed, breastfeeding was equally distributed across the social class, not something that is just practiced by the rich and educated.

The researchers found that most of the babies, irrespective of social class, were breastfed. Some of them were breastfed for less than a month and others for more than a year.

They saw that the ones, who were breastfed for longer time, scored higher on the measures of intelligence as adults and had more chances to earn a higher wage and to have completed more schooling.

Dr. Horta said that breast milk may offer an advantage as it is a good source of long-chain saturated fatty acids that are important for the development of brain.

The experts have said that the study findings can’t give the full confirmation about it and more research is required to explore any possible link between breastfeeding and intelligence.