A new study from the University of Pittsburgh Medical Center reveals that maintaining a positive outlook can protect women from various heart-related illnesses, while having a negative outlook can increase those risks.

Researchers included more than 162,000 postmenopausal women in the study, which lasted over 15 years. None of the participants had heart disease at the outset, and they were asked to answer several yes-no questions to assess their optimism and cynicism/hostility. Both metrics were considered independently of one another.

After eight years of careful monitoring, the team found that optimistic women were 9 percent less likely to develop heart conditions and 14 percent less likely to die from any cause than those who scored the lowest for optimism.

Conversely, those who scored the most highly for cynicism showed a 16 percent increased likelihood of premature death.

While some of these differences are believed to be purely physiological, some are thought to be related to behavior. "Someone who believes that life is not worth living probably isn’t the type of person who goes to the gym three times a week," said American Heart Association spokesman Dr Barry J. Jacobs, quoted by WebMD.

While improving one’s outlook on life is not a simple task, meditation and yoga have proven effective in helping some to become more serene. St. John’s Wort and omega-3 fatty acids may also help cope with difficult emotions.