MAR 20, 2015 2:57 PM PDT

Breast-feeding duration linked with smarter, richer adults

WRITTEN BY: Will Hector
The short-term benefits of breast-feeding are well known, but infants who were fed breast milk for 12 months or longer experienced benefits into adulthood, according to a study published in the April issue of Lancet Global Health.

The longitudinal study originated in Brazil in 1982 with 5,914 newborns. At age 30, these subjects showed a statistically significant bump in IQ test scores, income level, and educational attainment.

The observational study accounted for confounding social factors-such as socioeconomic status, maternal education level, smoking, and birth weight-that can skew the impact and meaning of breast-feeling studies.

"I don't want to terrify people who did not breast-feed or who breast-fed for a short time," lead author, Bernardo Lessa Horta, an associate professor at the Federal University of Pelotas in Brazil, told the New York Times. "It isn't only breast-feeding that affects I.Q. and income. But our study does show that breast-feeding is important and should be encouraged."

The study was able to locate 68 percent of the original neonates, interviewing 3,701 of the participants in 2012 and 2013 (and considering the 325 known to have died). Complete IQ and breast-feeding information was available for 3,493 members of the original study.

In 1984, when the average age of participants was 19 months, infant feeding data was gathered on the duration of breast-feeding and age at which supplementary food was introduced for study participants. For participants not interviewed in 1984, this information was obtained when they were seen in 1986 at a mean age of 42 months.

The researchers defined duration of predominant breast-feeding as the age when foods other than breast milk, tea, or water were introduced. Because families reported a high incidence of breast-feeding, researchers combined participants who had never been breast-fed with those who were breast-fed for less than one month. They indicate that evidence suggested a misclassification between these two categories.

The study also cited other supporting studies. One Belarus study demonstrated IQs at 6.5 years of age were, on average, 7.5 points higher in a group whose mothers received breast-feeding promotion. In a UK study, mean IQ was higher in children who received breast milk than in those who received formula.

The researchers wondered whether the benefits they discovered might be attributable to biological components of breast milk itself or if they might be explained by mother-infant bonding or intellectual stimulation, either of which could be keyed through breast feeding. They add that even after controlling for home environment or stimulation, scientific literature supports a positive link between breast-feeding and cognitive testing, suggesting a positive impact of breast milk on intelligence.

Although clear associations between breast-feeding and child intelligence have been made in previous research, and some evidence also exists to suggest positive long-term effects on adult intelligence and educational achievement, the authors assert this as the first study to show a positive association with adult earnings.

Source: The Lancet Global Health
About the Author
  • Will Hector practices psychotherapy at Heart in Balance Counseling Center in Oakland, California. He has substantial training in Attachment Theory, Hakomi Body-Centered Psychotherapy, Psycho-Physical Therapy, and Formative Psychology. To learn more about his practice, click here:
You May Also Like
JAN 16, 2020
Health & Medicine
JAN 16, 2020
Babies in Africa Receive World's First Malaria Vaccine
Would you accept a vaccine that was only 40% effective? For those at risk of malaria, the answer is likely a resounding, "yes!" According to the...
JAN 17, 2020
JAN 17, 2020
Toxic Metals and Cardiovascular Risk
A meta-analysis was recently published in the British Medical Journal to try and understand if there was a link between heart events and exposure to toxic ...
JAN 24, 2020
Cannabis Sciences
JAN 24, 2020
Sting Operation: Underage Customers Can't Buy Cannabis
Cannabis retailers in Colorado, Washington and Oregon have received top marks in secret tests to determine whether they were selling to underage buyers (yo...
FEB 03, 2020
Genetics & Genomics
FEB 03, 2020
Advances in Genetics From the GenomeAsia 100K Project
Scientists are taking note of the lack of diversity in genetics, and some are trying to fix the problem, which affects everyone....
FEB 15, 2020
Clinical & Molecular DX
FEB 15, 2020
FDA nod for AI-powered technology to detect strokes
The US Food and Drug Administration (FDA) has provided clearance for a novel technology that uses artificial intelligence (AI) to detect strokes. The platf...
FEB 12, 2020
Genetics & Genomics
FEB 12, 2020
Vapers Have Epigenetic Alterations Like Those Seen in Smokers
The activity of genes can be altered with chemical tags that get added to the genome, so-called epigenetic modifications....
Loading Comments...