Coffee could hold the secret to keeping bad breath at bay. The beans contain compounds that prevent bacteria releasing the gases behind halitosis, research shows. Pinpointing the key chemicals could lead to coffee 'mints' or pastilles that stop bad breath at the source.

Professor Mel Rosenberg, who has spent two decades studying the diagnosis and treatment of halitosis, actually set out to investigate why coffee causes bad breath. But his work at Israel's Tel Aviv University showed that while it may cause problems in our mouths, it has quite the opposite effect in the test tube.

Professor Mel Rosenberg, who has spent two decades studying the diagnosis and treatment of halitosis, actually set out to investigate why coffee causes bad breath. But his work at Israel's Tel Aviv University showed that while it may cause problems in our mouths, it has quite the opposite effect in the test tube.