It is a social offense that has often stumped — not to mention, offended — the masses.

But researchers say they're closer than ever to closing in on the cause of bad breath, according to a report in the New Zealand Herald.

Scientists including dentists, chemists, microbiologists and psychologists who attended the International Conference on Breath Odor Research in Chicago last week said their studies have run the gamut from which flavor best minimizes bad breath — cinnamon's a good choice — to the links between exhaled air and disease.

Click here to read the New Zealand Herald story.

This is what they know to date:

— About 90 percent of bad breath originates on the tongue

— For most, bad breath occurs when bacteria in the mouth breaks down proteins, producing volatile sulfur compounds that produce a foul smell

— Dry mouth, tooth decay, certain prescription drugs, sinus problems and diseases such as diabetes can cause bad breath

— Between 4 percent and 17 percent of people who seek treatment for bad breath don't actually have it

So, how do you prevent it? Good oral care — brushing, flossing and using a tongue scraper and mouth wash — is the best prevention, said Patricia Lenton, a clinical researcher at the University of Minnesota's School of Dentistry.