Researchers said they found some evidence that keeping babies off cow's milk may help prevent the development of type 1 diabetes in children with an inherited risk of the disease.
The children will have to be followed for years to be sure, but the Finnish researchers found indirect evidence that giving the babies a special formula may have helped.
The study of 230 Finnish infants who had stopped receiving breast milk was a preliminary test of the treatment. A much larger study of 2,160 babies, now ongoing in 15 countries, is expected to provide a definitive answer to the question in 2017.
The goal is to prevent type 1 diabetes, which typically strikes in childhood and requires a lifetime of careful management, including regular insulin injections. It is believed to be caused when the body's immune system mistakenly attacks insulin-producing cells in the pancreas.
This study involved infants who only got the formula when breast milk was not available.
Instead of a standard cow's milk formula, about half the babies were given a special formula in which the proteins found in the casein portion of the milk had been broken down into components too small to activate the immune system, a process called hydrolyzation.
Results of the pilot test, reported in the New England Journal of Medicine, showed that babies fed this hydrolyzed formula were less likely to develop telltale antibodies that are believed to pave the way for diabetes.
"Our results indicate that a preventive dietary intervention aimed at decreasing the risk of type 1 diabetes may be feasible," the researchers, led by Dr. Mikael Knip of the University of Helsinki, wrote.
Children given the cow's milk were twice as likely as the other children to develop one or more diabetes-related antibodies. The antibodies took anywhere from three months to 10 years to appear.
However, the pilot study was not large enough to tell if avoiding cow's milk reduced the actual risk of diabetes. Eight percent of the cow's milk recipients developed type 1 diabetes, compared to 6 percent who got the special formula, a difference that was not statistically significant.
"We did not expect a 100 percent prevention of clinical disease," Knip said in an e-mail.
All of the babies in the test -- and those in the larger study now underway -- have a genetic susceptibility to diabetes and had at least one family member with type 1 diabetes. They were followed until their 10th birthday.
Finland has one of the highest rates of type 1 diabetes in the world, with 64 new cases per year among every 100,000 children under 15.