Lungs have to do with triggerint the autonomous nervous system = in French we call this practice of healing through breathing Coherence cardiaque (heart coherence? heartbeat coherence). Dr David Servan-Schreiber has done a lot of promotion and he is fluent in English. If you do a Google serach with his name you are likely to find the English equivalent. I use this technique to cope with EVERY pain I get in my body. Real helpful.
Bad breath=presence of bacteria or yeast
Breathing can do MORE than just control the breath.