According to Dr. Stephen Post, author, Why Good Things Happen to Good People: How to Live a Longer, Healthier, Happier Life by the Simple Act of Giving, “Stress related health problems improves after performing kind acts. Helping reverses feelings of depression, supplies social contact, and decreases feelings of hostility and isolation that can cause stress, overeating, ulcers etc. (like fatigue.) A drop in stress may, for some people, decrease the constriction within the lungs that leads to asthma attacks.”
Whew. That is a lot of good that comes out of doing good.