Bottle-fed babies who graduate to solid food too early could be storing up weight problems for years to come.
A new study of babies' feeding habits suggests that in families who do not follow guidelines on weaning, the children may turn out to be heavier than expected by the age of five, and so may be at increased risk of obesity as they got older.
The research from the Children of the 90s study, based at the University of Bristol, suggests that the relationship between energy intake (in calories) and weight gain appears to be much stronger during infancy than in older children.
The fastest growing infants were those who had been fed formula-milk, rather than breast milk, and who were weaned onto solid foods at an early age, before 3 to 4 months old.
Dr Pauline Emmett, the study's senior nutritionist and a dietitian, says "It seems that breastfed infants are better able to regulate their energy intake than formula-fed infants.
"It could be because parents feeding formula milk make sure that the baby finishes the bottle and do not necessarily reduce the quantity offered once weaning is established.
"While there are obvious benefits in avoiding poor growth rates, excessive weight gain during infancy is also a problem as it may lead to increased risk of overweight or obesity in later life. Other studies have shown that greater dietary intakes during early infancy may have long-term effects on health and obesity."
The report's lead author Dr Ken Ong, from the Medical Research Council Epidemiology Unit and the University of Cambridge, says "There is a growing awareness through studies such as Children of the 90s that some infants may be fed excessively and develop a higher risk for overweight or obesity when they are older.
"Future studies are needed if we are to identify such infants. Until then it is best to follow the current Department of Health and WHO guidelines, which recommend the promotion of breast feeding and introduction of weaning foods at around 6 months of age".
Dr Emmett says that by the age of 4 months, 75 per cent of babies in Britain are drinking formula rather than breast milk.
"It could be that more advice should be made available about weaning, tailored to the particular needs of formula-fed infants.
"In the push to persuade mothers to breast feed, which of course is the first objective, perhaps we have neglected to provide adequate information to formula feeders."
Source: University of Bristol
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