Modern medical records show that at least 80% of people breathe incorrectly. Poor breathing habits lead to headaches, sleeping problems, neck pain, overworked neck and chest muscles, strained cognitive functioning and more. This can be a factor in chronic absenteeism. Learning to breath properly is one of the simplest and most profound ways to improve one's health and mental clarity, as well as to neutralize stress.
This is how I learned of the benefits of deep breathing: I lived in a tiny unspoilt village in Sri Lanka for a total of a year, and almost every day I would go snorkeling beyond the big waves. I would go down about 5 meters and grab hold of rocks to be able to stay underwater longer, so that I could see the beautiful big fish. I would stay as long as I could, then come up for 6 deep breaths, then go back down. I could stay underwater for 2 1/2 minutes, and do this for an hour or more. When I would come out of the water I would notice that my mind was so quiet yet focused, I would feel deeply at peace and connected to all the nature around me. Later I noticed that I hardly ever got sick and that the bronchittis I was plagued with as a child and adult had mostly disappeared. I even was able to hold my breath for 4 minutes, something I never could have imagined. When I finally started doing yoga 7 years later, I realized I had been doing advanced yogic breathing (pranayama) when snorkeling in the ocean.