5. Being happy. Everybody has bad days, and often this means going for the comfort food (mine is dark chocolate!) However, if you are having one of those days, it is much healthier, and you feel much better afterwards, if you do some exercise. Run, walk, dance, skip, hit a ball or do anything else you can think of for a while, and those feel-good chemicals will start coming into your brain, making you feel that life's OK after all!