Elementary school boys who had nursed mother’s milk for at least six months immediately after birth outpaced their classmates in reading, writing and arithmetic, according to a study published in the journal Pediatrics and reported by Reuters Health.

For the study, researchers tracked pregnant mothers then evaluated their breastfed kids until age 10 (moms must have started breastfeeding kids from at least 6 months old). Scientists also collected data about family income, education levels and how often parents read to kids. This was so they could take into account other factors that could explain the link between breastfeeding and academic achievement.

Researchers found that breastfed boys in the study scored an average of 10 percent higher in math and writing, 8 percent higher in spelling and 6 percent higher in reading compared with counterparts who didn’t nurse.

Many scientists believe breastfeeding lowers an infant’s risk of diarrhea, ear infections and sudden infant death syndrome (SID). What’s more, researchers think well-nursed babies may also enjoy long-term health benefits such as lowered asthma, obesity and diabetes rates.

“We know that breast milk, if the mother has a good diet, is the optimum and ‘best’ way of feeding a newborn baby—boys and girls—until at least six months and beyond,” said Wendy H. Oddy, lead researcher and fellow at the Telethon Institute for Child Health Research in Perth, Australia.

But while breast milk does contain essential fatty acids that help brain development, no one has established a direct link between mother’s milk and a higher IQ development.

In addition, breastfeeding wasn’t the strongest indicator of academic achievement for boys. The biggest benefit on that front was linked to parents reading to their children.

And what about girls? Well, researchers haven’t gotten the same results for females. Breastfeeding could affect kids differently because breast milk estrogens benefit boys more than girls. And what’s more, it’s also possible that boys get a bonding boost during breastfeeding, Oddy suggested.

Currently, the World Health Organization and the American Academy of Pediatrics recommend mothers exclusively breastfeed kids for their first six months of life then add solid foods to their breast milk menu.

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