BAKERSFIELD, Calif. -- Keeping a positive attitude may be able to reduce your risk of dying from heart disease.

Researchers from Duke University followed more than 2,800 patients with heart problems and found that optimists were half as likely to die over the course of the study. The finding held true even after doctors accounted for other factors such as the severity of the patients' illness, their age, and depression levels.

Experts have many theories about why optimism may contribute to heart health. Studies show that optimists tend to take better care of themselves -- they are more likely to take their heart medications as prescribed and to follow doctors' orders about exercising and eating a healthy diet.

Another possibility is that pessimists have more stress, which causes inflammation in the bloodstream and increases heart risk.

While optimism is a trait often present from birth, experts said people can improve their well-being with positive thinking -- by counting their blessings, always hoping for the best and not dwelling on negative emotions.