You can blame decaying food, dental cavities, acid reflux, etc for your bad breath but you better try to get some relief:

If you've eaten garlic – try parsley : the plant’s natural oils can neutralize the scent

If you had coffee – use the big red gum: germ killing cinnamon cuts bacteria by 50%

Meat gives you bad breath? – use mint floss: decaying hunks between the teeth are the main cause of bad breath

After eating cheese – drink some black tea: it rinses away proteins; antibacterial properties reduce stinky plaque