Mahatma Gandhi, as you know, walked barefoot most of the time, which produced an impressive set of calluses on his feet. He also ate very little, which made him rather frail.
Add this to the fact that he ate an odd diet, and it isn't surprising that he suffered from bad breath. This made him (oh man, this is so bad, it's good) a super calloused fragile mystic hexed by halitosis.