Yes, happiness is the key to healthy life. In a study, U.S. researchers found that people living happy and satisfied life make their future life healthier. Researchers analyzed the data collected in Australian surveys conducted in 2001 and 2004.

In these surveys, nearly 10,000 adults were asked various questions regarding satisfaction with life, happiness, presence of long-term, limiting health conditions and physical health. Researchers found that level of happiness and life satisfaction determined excellent, good or very good health.

Lead author Mohammad Siahpush of the University of Nebraska Medical Center in Omaha said, "Everything being equal, if you are happy and satisfied with your life now, you are more likely to be healthy in the future."