THURSDAY, July 27 (HealthDay News) -- Adding a supplement to infant formula that encourages the growth of beneficial intestinal bacteria lowers the chances of high-risk babies developing eczema, an international team of researchers report.

Using this "prebiotic" boosts the development of an immature immune system, the scientists explained, and that can help prevent allergies. Human breast milk contains natural prebiotics.

In the study, researchers made an infant formula based on the prebiotic content of human breast milk, and tested it on a group of high-risk babies. At least one parent of each child had a history of eczema, hay fever or asthma. The study was published in the July 26 online issue of the Archives of Disease in Childhood.

Infants who develop eczema are likely to develop other allergies as they age. In fact, 75 percent of infants who have eczema go on to develop hay fever, and half of those will go on to develop asthma.

The infants were placed into two groups: 102 were given a prebiotic formula, and 104 were given a normal formula.

Over six months, 10 babies receiving the prebiotic formula developed eczema, compared with 24 who received the normal formula.

"Although further studies are needed to understand completely the mechanism behind the immune-modulating effect of the studied prebiotics, the data support the potential role of prebiotics as dietary manipulation for primary allergy prevention during infancy," the study authors concluded.

The study, done by German, Italian and Dutch researchers, was partially funded by Numico Research Friedrichsdorf, a subsidiary of the Numico infant nutrition food company.

One expert thinks the use of prebiotics to prevent infant allergies will continue to grow, but he cautions that more research is needed before this approach is proven.

"This study demonstrates for the first time that prebiotics given to human infants decreases the likelihood of atopic dermatitis," said Dr. Martin G. Martin, a professor of pediatric gastroenterology and nutrition at Mattel Children's Hospital at the University of California, Los Angeles.

Martin noted the prebiotic was given to children who were at high risk for developing eczema. However, most infants who develop eczema do not have a family history of the disease or of any allergies, he said.

"It would be nice to look at the broader population, where 80 percent have no family history of allergies," Martin said. "It would be nice to see if these prebiotics have the same beneficial effects in this group."

Prebiotics may be the wave of the future in preventing childhood allergies, Martin said. "But these results need to be repeated to see if this first observation is true," he said. It remains to be seen if using prebiotics to prevent eczema also prevents hay fever and asthma from developing, Martin added.