Higher-Octane Breast Milk

Who would have guessed that the longer babies nursed, the better the nutritional content of their mother’s milk?

Women should breastfeed for one year or longer to give their baby the full benefits, pediatricians say. Such payoffs as increased immunity to disease, lower risk for allergies and a slower-but-healthier growth rate have long been noted in breastfed infants, but who would have guessed that the longer babies nursed, the better the nutritional content of their mother’s milk?

Israeli researchers recently conducted one of the first studies to measure the nutrient value of breast milk. They compared the milk of women who had been breastfeeding for more than one year with that of similar mothers who had been lactating for two to six months and found that the proportion of fat and calories in milk increased with the duration of breastfeeding. The fat content of milk from mothers who had nursed for over one year was 11 percent compared with 7 percent in the short-term group.

Experts have not yet determined the impact of this higher fat and calorie content on a child’s health. But, says lead author Dror Mandel, M.D., of Tel Aviv Medical Center, “many people’s impression is that if you continue to breastfeed beyond a year, the nutrient value probably drops. The results of our study are quite different … it might be that because the [older] infant is breastfed fewer times a day, the milk is more concentrated.” — SHARI ROAN      PEDIATRICS