If you put the words “causes of bad breath” into the search box at the top of this page, you will get a search result of hundreds, perhaps thousands of pages that will all tell you the exact same thing. Bad breath is caused by bacteria in the mouth that emit sulfur. You can increase the levels of those bacteria by eating only protein rich foods, drinking alcohol, and smoking cigarettes. If you’re doing any of these things in excess and have bad breath, stop doing them and it might go away.
Pure protein diets, like those that encourage you to eat lots of meat and no bread, create an environment in your body that is an ideal breeding place for the anaerobic bacteria that causes bad breath. These bacteria feed on amino acids and reproduce in dry, oxygen deprived settings like a dry mouth. The protein-rich foods supply the amino acids; smoking and drinking alcohol create the dry mouth situation. Think about that after your next steak dinner, bottle of wine, and after-dinner cigar.
Everyone needs a vice or two, but it’s important to understand when the combination of vices can be harmful in other ways. You will not smell your bad breath. The body’s senses are seldom aware of its own odor. Those around you may not have the inclination or ability to tell you, but there’s a good chance, if you’re eating protein heavy foods, smoking and drinking, that your breath might just have a foul odor to it.