CHICAGO (Reuters) - On the list of social offenses, bad breath ranks right up there with flatulence and body odor.

And while store shelves are well stocked with remedies ranging from chewing gum and mouthwash to breath strips and drops, researchers are just starting to understand the science of bad breath.

"It's taboo," said Patricia Lenton, a clinical researcher at the University of Minnesota's School of Dentistry. "You are typecast as the smelly person."

Lenton was one of nearly 200 scientists who attended the International Conference on Breath Odor Research this week in Chicago. Attendees ranged from dentists, chemists and microbiologists to psychologists and even flavor researchers.

Their research ran the gamut from studies on the most effective natural flavors for treating bad breath -- cinnamon is a good choice -- to the development of an artificial nose for sniffing out oral malodor and links between exhaled air and disease.

"We want to advance the science in this field," said Christine Wu, a researcher at the University of Illinois at Chicago's College of Dentistry, who helped organize the conference.

"In dental research, bad breath is neglected because it is not a disease that will kill people," she said in an interview. "But it's a huge problem. Everybody suffers from bad breath at one point in their lifetime."

For most, bad breath occurs when bacteria in the mouth breaks down proteins, producing volatile sulfur compounds that make for foul-smelling breath.

Dry mouth, tooth decay, certain prescription drugs, sinus problems, even diseases like diabetes can cause bad breath.

Most bad breath originates in the mouth, and about 90 percent of the smell comes from the tongue, Lenton said.

"It's warm. It's moist. It's like a large incubator of bacteria," she said.

Lenton said good oral care is the best weapon for routine bad breath. She recommends regular brushing and flossing, a tongue scraper to remove bacteria from the back of the tongue, and a final rinse with antibacterial mouthwash.

For some, however, it is not actual bad breath that's the problem. Lenton said anywhere from 4 to 17 percent of the people who seek treatment for breath odor are convinced they have bad breath -- even though they do not.

It is a condition some refer to as halitophobia, or the fear of bad breath, and it can interfere with daily life.

"It's an obsessive compulsive disorder," Lenton said. "There have been documented cases in Japan of people committing suicide from this."

Lenton and Wu hope the conference and others like it will raise the profile of breath research.

"In our culture, it's a difficult thing to talk about," Lenton said.