Are you an introvert? Do you find it difficult to express your feelings? You better step out of your cocoon and start to socialise more. According to a 30-year-study, men and women who bottle up their emotions are 50% more likely to die from a heart disease or stroke.

Researchers from Chicago's Northwestern University followed 2,000 men over three decades and recorded all possible health changes they underwent. At the beginning of the study, the men, aged 40-55 years, filled in questionnaires designed to gauge their levels of sociability.

By the end of the study, almost 1,000 had died of heart problems and 412 from other causes. Heart deaths included 404 from coronary heart disease such as heart attacks and strokes and 541 from cardiovascular diseases, which include other heart and circulation illnesses. Scientists then tabulated the accumulated data over the 30-year period keeping in mind other factors like high cholesterol, diet and smoking and found a direct link between shyness and onset of heart disease.

The conclusion was that sociable men have healthier hearts than their more reserved friends. The researchers, who announced their research in the journal 'Annals of Epidemiology', however, failed to explain why unsociable men should have more heart problems. According to them, one reason could be that introverts lead more sheltered lives and so find new situations more stressful. Alternatively, the part of the brain that controls the day-to-day running of the heart may also be involved in setting personality traits.

According to cardiologist K K Aggarwal, humans have three types of emotions - suppressive emotion when one keeps things to themselves, expressive emotion like throwing tantrums and showing anger and neutralising emotion in which a person balances the situation and expresses anger or sadness at the appropriate time.