Why Your Breath Smells Bad

Obviously, right? Yep, morning breath is pretty much a given, but here's why it happens: While you're sleeping peacefully, the bacteria in your mouth are anything but. The bugs take advantage of the fact that your production of saliva slows way down during sleep—and since your saliva helps "clean" your mouth, your breath might have a bad odor until you brush your teeth the next morning. Morning breath is totally normal, but some researchers refer to it as "morning halitosis."