A study of 1,312 children and mothers shows that breastfeeding for a full year can boost language development and IQ.

The conversation around breastfeeding usually centers on its health benefits. But more important, perhaps, is to ask how long you should breastfeed before switching to formula.

A recent study published in JAMA Pediatrics shows that breastfeeding for a full year may increase your child’s language skills and overall IQ. Currently, only one in four American women do so. If you have the chance to give your child a leg up, even before preschool, you may want to put the formula back on the shelf for the first 12 months.

Researchers from the Boston Children’s Hospital and Harvard Medical School followed 1,312 children and mothers over the course of seven years. They discovered that consistent, sustained breastfeeding during the first year of life improves children’s cognitive abilities more than breastfeeding for only six months.

At 3 years of age, language development is better in children who have been breastfed for 12 months, and at 7 years of age, their verbal IQ is better. Put another way, breastfeeding for the first year of life would be expected to increase a child’s overall IQ by about four points.

“For women who are able to breastfeed, I think these findings should be helpful in deciding how long to breastfeed and whether to supplement with formula before 6 months of age,” study co-author Mandy Brown Belfort, M.D., M.P.H., an assistant professor of pediatrics at Harvard Medical School, told Healthline. However, she notes, many other factors affect the decision of whether or not to breastfeed, including time, resources, and the health of the mother.

There have been suggestions, but no hard data until now, to support longer-term, consistent breastfeeding. For some women, part- or full-time formula feeding is the only option, but this study shows that, if possible, it’s better for a child’s development to continue breastfeeding until his or her first birthday.

The study cites the nutrients in breast milk, such as the n-3 fatty acid docosahexaenoic acid (DHA), as being potentially beneficial for brain development. Getting these fatty acids is extremely important, especially, it turns out, when DHA is delivered consistently for 12 months.

“We were able to show the impact of partial versus exclusive breastfeeding, and also the length of breastfeeding over the first year of life,” Belfort said. To increase the amount of DHA in your breast milk, the researchers recommend eating more fish.

If you haven’t jumped on the breastfeeding bandwagon, you’re not alone. In the United States, just over 47 percent of women breastfeed for a full six months after birth, and only 25.5 percent breastfeed for a full year, according to the Centers for Disease Control and Prevention (CDC).

It’s time to buck this trend. Having a baby less than 1 year old can be draining (lack of sleep, lack of showers, lack of a seemingly normal life…), but exclusive breastfeeding for at least one year may be highly beneficial in the long run.