LONDON (Reuters) - Breast-feeding could reduce a baby's risk of suffering from childhood obesity by up to 30 percent, doctors said Friday.

Breast milk is full of nutrients that protect the infant from infections, allergies, vomiting and diarrhea and may also aid the child's development.

Doctors at the Royal Hospital for Sick Children in Glasgow, Scotland, have produced new evidence to support the theory that breast-fed babies are less likely to become obese as they grow older than babies fed formula.

"Our findings suggest that breast-feeding is associated with a modest reduction in childhood obesity risk," said Dr. John Reilly, who headed the research team.

The impact of breast milk on obesity was evident in early childhood and could have implications for strategies to reduce obesity, which has risen to epidemic proportions in many industrialized countries.

Obese children tend to become obese adults and have a higher risk of suffering from diabetes, heart disease, stroke and other ailments linked to excessive weight. "Breast-feeding is therefore potentially useful for population-based strategies aimed at obesity prevention, particularly with the other benefits that breast-feeding provides," Reilly added.

In research reported in The Lancet medical journal, the doctors studied the impact of breast-feeding on 32,000 Scottish children by measuring their body mass index (BMI) when they were 39 and 42 months old.

BMI is calculated by dividing weight in kilograms by height in meters squared.

They discovered that obesity was less common among the breast-fed than the bottle babies after adjusting for factors such as birth weight, sex or socioeconomic status.