Breastfeeding improves a child's chance of climbing the social ladder and becoming a successful adult, according to a long-term study.
The health benefits of breastfeeding are well known, but the study is among the first to identify tangible benefits later in life.
Two groups of people - born in 1958 and in 1970 - were categorised by the job their father did when they were 10 or 11, and the job they themselves had when they were 33 or 34.
Social class was divided into four categories based on job type - from unskilled and semi-skilled manual work to professional or managerial work.
The analysis of more than 34,000 people found that those who had been breastfed as a baby were 24 per cent more likely to move up the social hierarchy and 20 per cent less likely to drop down.
The authors of the study, published in the medical journal Archives of Disease in Childhood, said that it provided evidence of long-term health, developmental and behavioural advantages to children, which crucially persist into adulthood.
Breastfeeding enhances brain development, which boosts intellect, which in turn increases upward social mobility, they argued.
"There are few studies that look at the long-term outcomes of breastfeeding, but this study shows its long-lasting positive effect," said Professor Amanda Sacker, one of the report's authors and the director of the International Centre for Lifecourse Studies in Society and Health at the University College London.
The NHS recommends breastfeeding to new mothers for the first six months of a baby's life.
Breast milk protects children from infections, and breastfed babies are also less likely to become obese or develop eczema.
The report's authors said that breastfeeding also helped to generate a strong emotional bond between mother and baby.
"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 breastfed infants," they said.
Professor Sacker said that mothers who could not breastfeed could still aid their baby's emotional and cognitive development with cuddling and close skin-to-skin contact with their baby while feeding.
The study comes after figures that revealed the number of women breastfeeding their babies in England has dropped for the first time in a decade.
Numbers have been increasing in recent years, following a long-term decline associated with more women working and the increasing use of baby formula. Independent
Babies who were breastfed:
• 24 per cent more likely to have a "better" category of job than their father did.
• 20 per cent less likely to have a "worse" category of job.
• Based on a study of 34,000 people born in 1958 or 1970.