Let us begin by defining nutrition as the process by which living beings use food to get nutrients for energy, growth, development, and maintenance of the body cells. Bad breath or halitosis is an unpleasant odor caused by waste from bacteria inside your mouth, decaying food, other debris and poor oral hygiene.

It is very common that certain foods may result in a temporary bad odor, such as garlic, onions, curry and other spices.  Furthermore, the use of tobacco and dry mouth increase the chance of halitosis. The malodor is just as unpleasant to you as the others around you.

For a healthy body and a healthy immune system, it is essential to have all types of antioxidants present.  That is why proper diet plays a major role in keeping everything in balance.  Practicing good oral hygiene will result in lowering the possibility of bad odor in the mouth. This includes flossing, scraping your tongue to remove the bacterial build-up, food debris, and dead cells from the surface of it, proper brushing techniques and rinsing if applicable.

If you suspect that you may be suffering from bad breath, do not hesitate to ask your dentist, he or she can help determine its source.

For further reading please refer to http://www.mayoclinic.org/diseases-conditions/bad-breath/symptoms-causes/dxc-20192379