Feb. 14, 2007 -- Breastfed babies are likely to become better educated and more upwardly mobile adults than their bottle-fed peers, according to a new British study.
The study began in 1937 and tracked 1,414 British children into late adulthood.
It found those breastfed as infants were 41% more likely to move up the social ladder, according to Richard Martin, BM, BS, PhD, an epidemiologist at the University of Bristol, in England, and an author of the study.
However, Martin is quick to offer a caveat: "It's very possible that the effect is not due to breastfeeding per se, but something to do with the mothers' choice to breastfeed, or the environment in which the child grew up in, that may be more important," he tells WebMD.
At its start, the study included more than 3,000 children from 16 urban and rural areas across England and Scotland, monitored from birth as part of the Boyd Orr Study of Diet and Health in Pre-War Britain.
When the study began, the children were about 7 years old.
The social class of the children's head of household was noted -- classified as professional and managerial, skilled, partly skilled, unskilled, or unemployed.
The prevalence of breastfeeding ranged from 45% to 85%, but whether a mother chose to breastfeed did not depend on household income, what the household spent on food, the number of siblings, birth order, or the social class of the family at the start of the study, the researchers found.
Follow-up questionnaires about educational achievements and social mobility were sent out in 1997 and 1998, when study participants were in their 60s and 70s.
In the follow-up, researchers again asked about social class based on occupation.
Breastfeeding Time Counts
The 1990s surveys showed that breastfed infants were more likely to complete secondary school; with 27% of breastfed versus 20% of bottle-fed graduating.
Breastfed babies were also more likely to move up in social class, based on occupation. Fifty-eight percent of breastfed infants moved up, compared with 50% of bottle-fed ones.
Fifty percent of bottle-fed infants stayed in the same social class or went downward, while only 42% of the breast-fed infants stayed the same or moved down.
The longer a child was breastfed, the more likely he or she was to be upwardly mobile.
Interpretation and Perspective
Martin's team says the findings could be explained by other studies' findings that breastfeeding benefits brain development, leading perhaps to better exam performance and job prospects.
Other studies have shown that breastfed infants enjoy a host of health-related benefits, including lower risk of infections and protection against chronic diseases and psychiatric disorders.
The study results are interesting, says Dennis Woo, MD, chairman of the pediatrics department at Santa Monica -- UCLA and Orthopaedic Hospital, in Santa Monica, Calif. "The bottom line is, we certainly should support breastfeeding," he says.
But he notes that in pre-World War II days, when these study participants were infants, formulas were often homemade "and probably inconsistent," and that could have affected the results.
Given the standardized commercial formulas prevalent today, Woo says he is not sure the study findings would come out the same.
The study is published online ahead of print on Feb. 14, 2007, in the Archives of Disease in Childhood.