1. Helping others feels good. There is some evidence to suggest that when you help others, it can promote physiological changes in the brain linked with happiness. This heightened sense of well-being might be the byproduct of being more physically active as a result of volunteering, or because it makes us more socially active. 2. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.