Here in the U.S., it’s pretty common to see people looking shocked when a mother breastfeeds her baby in public. Mothers are often asked to relocate to baby stations located in restrooms, of all places, making for an unpleasant and unsanitary experience for both mother and child.

But a new study might help change that attitude, because it finds that breastfeeding for longer periods may lead to higher IQ, more education, and greater income.

Researchers at the Federal University in Pelotas, Brazil conducted the study, which was published in Lancet Global Health.

The study started in Pelotas, Brazil in 1982 with the enrollment of 5,914 newborns whose duration of breast-feeding and weaning age was recorded. This population was chosen because breastfeeding was evenly distributed by social class and not more common among highly educated, high-income women like in other countries.

“Once the results were analyzed, they saw that there was a positive association between how long the infants were breastfed and subsequent IQ, education level, and income.”

In a follow-up 30 years later, 68% of the participants (3,493 individuals) returned to take an IQ test and to be interviewed about a number of factors including education and income.

Researchers adjusted their data to account for differences such as parent’s education level, household income, whether the mother smoked during pregnancy, mother’s age at pregnancy, type of delivery, and birth weight.

Once the results were analyzed, they saw that there was a positive association between how long the infants were breastfed and subsequent IQ, education level, and income.

The participants who were breastfed for 12 months or longer scored, on average, about 3.7 points higher in IQ, achieved more years of education, and earned about 20% more than the average income level.

Study author Bernardo Lessa Horta, associate professor of Epidemiology at the Federal University of Pelotas in Brazil, said, “It’s more evidence that besides the clear short term benefits, breastfeeding also has long term consequences in terms of human potential.”

One possible reason for the apparent advantages is that breast milk is “rich in long-chain polyunsaturated fatty acids which are important to brain growth and development.”

Still, he noted that the study was observational and that other unmeasured factors that might influence intelligence and success could have had an effect.

He continued, “I don’t want to terrify people who did not breast-feed or who breast-fed for a short time. It isn’t only breastfeeding that affects I.Q. and income. But our study does show that breast-feeding is important and should be encouraged.”

The Bottom Line

There are plenty of good reasons to breastfeed infants. According to a number of sources, including the NRDC, the many benefits of breastfeeding include:

• Breastmilk is a nearly perfect mix of vitamins, protein, and fat.
• More easily digested than formula.
• Contains antibodies that help baby fight off bacteria and viruses.
• Provides beneficial bacteria that are crucial to proper digestive tract development and immunity, as well as prebiotics to nourish the good bacteria.
• Lowers risk of allergies or asthma.
• Helps with bonding.
• Helps lower risk of Sudden Infant Death Syndrome (SIDS).
• Linked to lower rates of illness such as ear infections, respiratory illness, and diarrhea.

Breastfeeding also benefits mothers by:

• Helping to burn extra calories (up to 500 calories/day) to help drop pregnancy weight
• Releasing the hormone oxytocin, which helps the uterus shrink back to pre-pregnancy size and helps reduce uterine bleeding after delivery.
• Lowers risk of breast and ovarian cancer.
• Lowers risk of osteoporosis.

So the next time we see a mother breastfeeding her baby in public, let’s be supportive! Just think of her as providing a nutritious meal for her infant, and at the same time, trying to give her baby the best chances at success in life.