Babies who are breastfed are less likely to have behaviour problems by the time they reach the age of five than those who receive formula, scientists said.
British researchers who used a "strengths and difficulties" questionnaire completed by parents found that abnormal scores were less common in children who were breastfed for at least four months.
Maria Quigley of the national perinatal epidemiology unit at Oxford University, who led the work, said the findings "provide even more evidence for the benefits of breastfeeding".
Struggle to breastfeed
Mothers who want to breastfeed should be given all the support they need. "Many women struggle to breastfeed... and many don't receive the support that might make a difference," she said in a statement.
As reported May 9th in the Archives of Disease in Childhood, researchers from the universities of Oxford, Essex, York and from University College London used data from the Millennium Cohort Study, a nationwide British survey of babies born in 2000-2001. They had information on more than 9,500 babies born at full term to families of white ethnic background.
They found abnormal scores for the questionnaires, which indicate potential behavioural problems, were less common in children breastfed for at least four months - at 6% -than in formula fed children - at 16%.
The lower risk of a full-term breastfed child having abnormal scores for behaviour was also evident even when the researchers accounted for other influences such as socio-economic or parental factors.
"We're not necessarily talking about tear-away, unmanageable five-year-old kids," said Quigley. "It might be unusual anxiousness, restlessness, inability to socialise with other children or play fully in groups."
The researchers said one possible reason for the findings was that breast milk contains large amounts of essential long chain polyunsaturated fatty acids, growth factors and hormones which are important in brain and nervous system development.
The results might also be explained by the fact that breastfeeding leads to more interaction between mother and child and better learning of acceptable behaviours, they said.
Peter Kinderman, a professor of clinical psychology at the University of Liverpool, who was not involved in the study, said it was a good piece of research with important findings.
"Positive bonding between parent and child is known to be fantastically helpful for development," he said. "This is more evidence of the importance of breastfeeding and mother-baby attachment, not just for physical health but also for the psychological development of the child." (Reuters Health/ May 2011)
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