Besides decreasing women’s risk of developing breast cancer, breast-feeding was also found to make children significantly smarter, improving their abilities to read and write, Canadian research reveals.

Dr. Michael S. Kramer, of McGill University and the Montreal Children’s Hospital in Canada and his colleagues randomly assigned 7,108 infants in Belarus to exclusive breast-feeding while another 6,781 infants received the usual practice of breastfeeding plus other foods.

By the time the kids reached 6.5 years, they were given a standard IQ test, which showed that exclusively breast-fed children scored, on average, 7.5 points higher in verbal intelligence, 2.9 points higher in nonverbal intelligence and 5.9 points higher in overall intelligence.

Additionally, teachers also rated these children as having better academic performance in both reading and writing compared with children who weren’t breast-fed exclusively.

“Mothers who breast-feed or those who breast-feed longer or most exclusively are different from the mothers who don't. They tend to be smarter. They tend to be more invested in their babies. They tend to interact with them more closely. They may be the kind of mothers who read to their kids more, who spend more time with their kids, who play with them more. Our study provides the strongest evidence to date that prolonged and exclusive breast-feeding makes kids smarter,” Dr. Kramer said, as quoted by Reuters.

Other experts think that nutrients in mother’s milk (which are not found in any other food) seem to contribute to brain development and increased IQ. Mother’s milk appears to contain certain amino acids, not found in baby formula, which include omega three fatty acids and DHA (Docosahexaenoic acid) that are very important for brain’s development.

“I'm not surprised because many studies have had similar results. It's wonderful to have this very large study to confirm what we've known or thought for a long time,” said Dr. Ruth Lawrence, a professor of pediatrics at the University of Rochester School of Medicine, and a member of the American Academy of Pediatrics executive committee section on breast-feeding, the Washington Post reports.

New mothers should breast-feed their babies exclusively for the first six months of their life and continue breast-feeding with baby food as a supplement until at least the baby’s first birthday, the American Academy of Pediatrics and the American College of Obstetricians and Gynecologists recommend. The World Health Organization and the American Academy of Family Physicians support the same thing.

A recent study by the Centers for Disease Control and Prevention found that more than three quarters of U.S. mothers breast-feed their babies, the highest rate in at least two decades. This could highly contribute to the number of kids having good scores at IQ tests in the future and not only, as breast-feeding was also found to protect against respiratory infections, obesity, diabetes and even cancer.