Being happy and naturally optimistic cuts the risk of developing heart problems, say researchers.

They found that those who are enthusiastic, contented and believe the glass is half full rather than half empty have a better chance of keeping their heart healthy.

It is the first study to find such a strong link between positive emotions and a lower risk of heart disease.

Findings published in the European Heart Journal reveal the potentially damaging effects of pessimistic thoughts and long-term negativity.

"This is the first study to show an independent relationship" between heart disease and a positive attitude that was spelled out through clear data, as opposed to just being based on a person's own report of their attitude.