Longer Breastfeeding Duration Tied to Higher Intelligence
Children who are breastfed longer have better receptive language at three years of age and verbal and nonverbal intelligence at seven years of age, a new study suggests.
While numerous studies have confirmed the link between breastfeeding and health benefits in infancy, researchers say evidence supporting the link between breastfeeding and better cognitive development is less conclusive.
Lead researcher Dr. Mandy B. Belfort of Boston Children's Hospital and her team assessed the links between breastfeeding duration and exclusivity with child cognition at ages three and seven years. Researchers also wanted to look at the extent to which maternal fish intake during lactation affected infant feeding and later cognition.
The findings revealed that longer breastfeeding duration was associated with higher Peabody Picture Vocabulary Test score at three years of age and higher intelligence on the Kaufman Brief Intelligence Test at seven years of age. However, researchers noted that breastfeeding duration was not associated with Wide Range Assessment of Memory and Learning scores.
Researchers found that children with mothers who consumed more fish during breastfeeding performed better on the Wide Range Assessment of Visual Motor Abilities test at three years of age. However, researchers note that this finding was not statistically significantly.
"In summary, our results support a causal relationship of breastfeeding in infancy with receptive language at age 3 and with verbal and nonverbal IQ at school age. These findings support national and international recommendations to promote exclusive breastfeeding through age 6 months and continuation of breastfeeding through at least age 1 year," researchers conclude.
Experts say that the findings suggest that breastfeeding an infant for the first year of life could increase a child's IQ for about four points.
"The authors reported an IQ benefit at age 7 years from breastfeeding of 0.35 points per month on the verbal scale and 0.29 points per month on the nonverbal one. Put another way, breastfeeding an infant for the first year of life would be expected to increase his or her IQ by about four points or one-third of a standard deviation," Dimitri A. Christakis, M.D., M.P.H., of the Seattle Children's Hospital Research Institute, wrote in an accompanying editorial.
"However, the problem currently is not so much that most women do not initiate breastfeeding, it is that they do not sustain it. In the United States about 70 percent of women overall initiate breastfeeding, although only 50 percent of African American women do. However, by six months, only 35 percent and 20 percent, respectively, are still breastfeeding," Christakis added.
"Furthermore, workplaces need to provide opportunities and spaces for mothers to use them. Fourth, breastfeeding in public should be de-stigmatized. Clever social media campaigns and high-quality public service announcements might help with that. As with lead, some of these actions may require legislative action either at the federal or state level. Let's allow our children's cognitive function be the force that tilts the scale, and let's get on with it," Christakis concluded.