Experts have warned mothers of small babies against overfeeding their children after research claimed that faster weight gain in infancy could make them overweight in later life.
A study by the University College London (UCL) Institute of Child Health found that infants who were fed milk enriched with nutrients had 22% to 38% more body fat mass by the time they were eight than children raised on standard formula.
Being fed too much at a young age and becoming overweight as an adult have been linked in research on animals but the study team said this is the first demonstration in humans when other factors such as the size of mothers is ruled out.
Professor Atul Singhal, from the MRC Childhood Nutrition Research Centre, UCL Institute of Child Health, who led the study, said mothers should breastfeed if possible.
He said: "It's easier to regulate appetite and harder to overfeed breastfed babies. If they can't breastfeed, they shouldn't overfeed because babies should not put on too much weight too quickly.
"Small babies will put on weight faster than other babies anyway as they try to catch up. Mothers should not add fuel to the fire by giving them any more to try to make them heavier than their percentile."