WASHINGTON, Jan. 2 (Xinhua) -- Drinking formula made with cow's milk did not increase the risk of developing Type 1 diabetes in children with genetic risk factors for the condition, a 15-year international study of more than 2,000 children said Tuesday.

The findings, published in the Journal of the American Medical Association, provided a long-awaited answer to the question of whether infant formula made with cow's milk plays a role in the development of Type 1 diabetes.

Previous studies have indicated that early exposure to complex foreign proteins, such as the proteins in cow's milk, may increase the risk of Type 1 diabetes in people with genetic risk for the disease.

Beginning in 2002, a team led by Dorothy Becker, a professor of pediatrics at the University of Pittsburgh School of Medicine, examined 2,159 infants in 15 countries to find out whether delaying the exposure to complex foreign proteins would decrease the risk of diabetes.

Each of the infants had a family member affected by Type 1 diabetes, as well as a genetic propensity for the disease that was determined with a blood test given at birth.

After breastfeeding, the babies were either weaned to a conventional cow's-milk-based formula with the cow's-milk proteins intact or a special formula in which the cow's-milk proteins were split into small pieces known as peptides.

That special formula -- called hydrolyzed-casein formula -- mimics the body's process of digestion, breaking down proteins into tiny parts.

Infants were fed the study formula for at least two months until the age of six to eight months and at the same time were given no cow's milk proteins from any other food sources.

Of the infants who consumed the conventional cow's-milk formula, 82, or 7.6 percent, developed diabetes during the 11.5-year followup period. For those who received the hydrolyzed-casein formula, 91, or 8.4 percent, eventually developed the disease.

The results showed no statistically significant difference between the two groups in terms of how many of these children developed diabetes.

"After more than 15 years of effort, this study puts to rest the controversy regarding the potential role of cow's milk formula in the development of type 1 diabetes," said Becker.

"This once more shows us that there is no easy way to prevent type 1 diabetes. Accordingly, there is no evidence to revise the current dietary recommendations for infants at high risk for type 1 diabetes."