American researchers who analysed data of about 7,000 children found that those regularly fed a bottle of milk when they are two years old are 30 per cent more likely to be obese by the time they are five-and-a-half.
The researchers, who detailed their findings in the Journal of Pediatrics, suggested that limiting prolonged bottle use in children may be an effective way to help prevent obesity.
For their study, the team from Temple University and the Ohio State University College of Public Health analysed data a large national study involving over 6,750 children born in 2001.
The team, who focused on the association between bottle use at 24 months of age and the risk of obesity at 5.5 years of age, found that 22 per cent of the children in the study were prolonged bottle users, meaning that at two years of age they used a bottle and went to bed with a calorie-containing bottle.
Nearly 23 per cent of the prolonged bottle users were obese by the time they were 5.5 years old, they found.
"Children who were still using a bottle at 24 months were approximately 30 per cent more likely to be obese at 5.5 years, even after accounting for other factors such as the mother`s weight, the child`s birth weight, and feeding practices during infancy," said study author Robert Whitaker of Temple University.
According to the researchers, drinking from a bottle beyond infancy may contribute to obesity by encouraging the child to consume too many calories.
"A 24-month-old girl of average weight and height who is put to bed with an 8-ounce bottle of whole milk would receive approximately 12 per cent of her daily caloric needs from that bottle,"explained co-author Rachel Gooze.
She noted that weaning children from the bottle by the time they are one year of age is unlikely to cause harm and may prevent obesity.
The authors also suggested that pediatricians and other health professionals work with parents to find acceptable solutions for stopping bottle use at the child`s first birthday.