At last, research is proving what poets have known for centuries - that the mind and heart share inextricable links. New studies show that socializing with friends, reducing stress and staying positive might be just as important for your heart as working out and eating healthfully. Conversely, negative emotions, such as stress, anxiety, hostility and depression, can be almost as damaging to your heart as smoking, staying sedentary and eating junk food.

When you feel happy and in control of your life, you're more likely to exercise, eat right, remember your medications and generally take care of yourself than when you're unhappy. And positive feelings (and your ability to deal with negative ones) have an even more direct effect on your heart. When you're unhappy or anxious, your body releases stress hormones that speed the heartbeat, constrict blood vessels, raise blood pressure, and over time, weaken the heart. But, by learning to keep negative emotions at bay, you can keep those stress hormones low.

Considerable evidence links happiness with healthy hearts. One study from the University of Pittsburgh showed that optimistic women had fewer signs of early heart disease than pessimistic women. Another study from the University of Maryland demonstrated that laughing at a funny movie for 15 minutes improved circulation in test subjects for up to 45 minutes afterward - a benefit much like the effect of aerobic exercise. The scientist who performed this study now recommends at least 15 minutes of laughter a day as part of a heart-healthy lifestyle.

Positive emotions also help hearts that aren't so healthy. Researchers at Duke University found that feelings of joy, optimism and euphoria were linked to increased survival in patients who had undergone cardiac catheterization procedures. University of Wisconsin scientists demonstrated that after heart disease patients learned to forgive people who had hurt them, the blood flow to their hearts decreased less when they recalled the painful incidents. This is healthier for the heart.

These findings are especially significant for women, who are particularly susceptible to negative emotions. Researchers at Johns Hopkins University found that women are more likely than men to experience "broken-heart syndrome," or a severe weakness in the heart muscle caused by sudden emotional stress. Women are also more likely to suffer from chronic depression, which can gradually sap mental and cardiovascular health.

Scientists are so convinced of this powerful mind/heart connection that they've developed a new field of medicine, behavioral cardiology, to study it. Researchers in this field include cardiologists, psychologists, nurses, dietitians and other healthcare professionals. Although the developments in behavioral cardiology are helping to educate physicians and patients, many doctors still don't make it standard practice to ask about their patients' state of mind.

That's why it's important for you to be proactive. Talk to your doctor about your emotional health as well as your physical symptoms. If you're constantly depressed, anxious or fearful, ask for a referral to a mental health professional. And find ways to cultivate serenity and happiness in your daily life - keep in touch with friends and family, take up meditation or yoga and never let your vacation days go to waste. You'll do your heart, your mind and your entire body a world of good.