Having a positive outlook also makes a person healthy. In fact, medical science has proven that stress, which causes many of today’s common illnesses such as high blood pressure, heart disease and cancer, can be avoided when people feel good about themselves. If you have a good sense of humor and laugh a lot, a chemical substance called serotonin will be released into your blood stream, giving you an immediate feeling of well-being and tranquility. It has also been found that the elderly recover faster from illness when they are cheerful. Being positive and happy is synonymous with health and longevity.