March 23 (HealthDay News) -- A new type of yogurt available in some Pacific Rim countries appears to help prevent and fight ulcers and gastritis, according to Japanese researchers.

The finding came from a study involving 42 people who had tested positive for the ulcer-causing bacteria Helicobacter pylori (H. pylori). They consumed two cups a day of regular yogurt or yogurt fortified with the antibody IgY-urease. By comparison, people who'd eaten the fortified yogurt had lower levels of urea, a urease byproduct, when retested a month later. That indicated less bacterial activity, according to the researchers, who were to present their finding March 22 at a meeting of the American Chemical Society in Salt Lake City.

"With this new yogurt, people can now enjoy the taste of yogurt while preventing or eliminating the bacteria that cause stomach ulcers," study coordinator Hajime Hatta, a chemist at Kyoto Women's University in Kyoto, Japan, said in a news release issued by the conference sponsors.

Antibiotics proved more effective at controlling the intestinal bacteria than the yogurt, the researchers said. But they believe that many people would prefer to add a few helpings of yogurt to their diet than to take medication, especially since the antibody doesn't seem to alter the taste of the yogurt or cause obvious side effects, Hatta said.

The yogurt -- already sold in Japan, Korea and Taiwan -- may not be for everyone, though. Hatta warned it may cause a reaction in people who have allergies to milk or eggs.

More than 25 million people in the United States have an ulcer at some point in their life, according to the U.S. Centers for Disease Control and Prevention.

Hatta's team created the antibody after noting that H. pylori relies on the protein urease to attach to and infect the stomach lining. They injected chickens with urease in hope the birds' immune systems would produce an antibody that could shield the stomach lining. The antibody, IgY-urease, was then harvested from the chicken's eggs, put in yogurt and tested on people with a known H. pylori infection.

Stomach acid eventually kills the IgY-urease antibody, the researchers said.

SOURCE: American Chemical Society, news release, March 22, 2009