New Research Links Longer Breastfeeding to Higher IQs and Earning Power

If you know any young moms, you know that one of their most common brunch debates involves how long you should breastfeed your baby.

Well, science has just given them something more to talk about.

Apparently, the longer you breastfeed you child, the higher your child’s IQ and earning ability will become in adulthood.

A study in Pelotas, Brazil – decades in the making – followed the lives of 3,500 newborn babies for 30 years. What researchers found was that, the longer mothers breastfeed, the higher their child’s intelligence in adulthood would be as well as their length of schooling and adult earnings.

They discovered a four-point difference in IQ at age 30 between babies who were breastfed for less than one month and those who were breastfed for more than a year.
Those who were breastfed for longer also had around an extra year of schooling and earned 341 more Brazilian reals per month by age 30 (or, 15% more).

“The effect of breastfeeding on brain development and child intelligence is well established, but whether these effects persist into adulthood is less clear,” says lead author Dr. Bernardo Lessa Horta from the Federal University of Pelotas in Brazil. 

In the population studied, breastfeeding was not more common among the more educated or high-income women, but was evenly distributed among the social classes. This was something unique from earlier studies that linked a longer duration of breastfeeding to higher intelligence levels. The problem with previous studies was that the research was conducted in higher income countries, where more socially and economically advantaged women are more likely to breastfeed than those who are less fortunate.

Meaning, intelligence levels could really be the result of other factors that come with economic advantages rather than solely on the duration of breastfeeding. 

In Brazil, however, unlike in the US or Canada, the proportion of mothers who breastfeed is about the same in every socioeconomic group.

Though there could admittedly be other factors at play in the findings, the study definitely strengthens the argument for longer time on the boob. 

What works such magic in that breast milk, anyway?
The authors cite the presence of long-chain saturated fatty acids found in breast milk that are essential for brain development.

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