Children who are breast-fed may be more likely to reach a higher social class than their parents, a new study finds.
The researchers looked at about 34,000 people in the U.K., either born in 1958 or in 1970, and compared their social class at the age 33 or 34 with that of their fathers when they were children. Among the study participants, those who had been breast-fed were more likely to have moved up the social hierarchy in adulthood, which the researchers defined as having a job of higher social status than their fathers.
The study found that while breast-feeding increased the chance of moving upward socially by 24 percent, it also reduced the chance of sliding downward by 20 percent.
The results suggest that breast-feeding improved children's neurological development, resulting in better cognitive abilities, which in turn helped them with their upward move in the society, the researchers said.
Breast-fed children in the study also had fewer signs of emotional stress, which could have contributed to their success later in the life, according to the study published today (June 24) in the journal Archives of Disease in Childhood.
Previous studies have suggested that nutrients in breast milk improve cognitive development. Similarly, skin-to-skin contact between mother and child has been linked to enhanced mother-child bonding, and reduced stress.
"Perhaps the combination of physical contact and the most appropriate nutrients required for growth and brain development is implicated in the better neurocognitive and adult outcomes of breast-fed infants," the researchers wrote in their study. [The Facts on Moms & Breast-Feeding]
For the study, the researchers asked mothers of two large groups of people born 12 years apart whether they had breast-fed their children.
They then compared people's social class as children — based on the social class of their father when they were 10 or 11 — with their social class as adults, measured when they were 33 or 34. Social class was based on different categories of occupations, from unskilled and manual, to managerial and professional jobs.
The researchers measured children's cognitive performance and stress response every few years. They found that cognitive abilities and stress scores accounted for about a third of the total impact of breast-feeding.
There is evidence that some constituents of breast milk, such as long-chain polyunsaturated fatty acids, are essential for neurological development of the child. The researchers said they suspect that there may be other nutrients in breast milk as well that support child's development.
The study also found that fewer children were breast-fed in 1970 than in 1958. More than two-thirds of children born in 1958 were breast-fed, compared with one-third in 1970.
The results suggest that there may be lifelong social benefits from breast-feeding, the study said. Such benefits may be even greater for more vulnerable children who are born preterm or with low birth weight.
Email Bahar Gholipour. Follow LiveScience @livescience, Facebook & Google+. Original article on LiveScience.com.