A good night's sleep could be the key to living longer. People who reach 100 are three times more likely to spend at least 10 hours a night in bed, scientists have found.

The research shows that health problems are associated with poor sleep quality. When we sleep, our cells regenerate and we also remove toxins and activate immune system cells, reports express.co.uk.

People who said they were in bad health were more likely to have poor sleeping patterns, the study found.

Fragmented sleep raises levels of blood fats, cholesterol, cortisol and blood pressure - all powerful risk factors for heart disease.

"Surprisingly, the oldest adults aged 100 and above were 70 per cent more likely to report good sleep quality than younger participants aged 65 to 79," said Danan Gu, of Portland State University in Oregon.

"Lack of sleep also reduces brain power and vigilance," he said.