Why eights hours’ sleep is key for health

WE’RE often warned of the dangers of too little sleep – but it seems too much may be just as harmful.

Sleeping for more than nine hours or less than seven hours a night could raise the risk of heart problems, experts say.

Both increase the chances of obesity, type 2 diabetes, high blood pressure, high cholesterol and clogged arteries, a major review concluded.

The American Heart Association has published a statement highlighting the links between poor sleep and cardiovascular health.

It said emerging evidence suggests that sleep alters the metabolism and hormone balance of the body, affecting cholesterol, insulin, blood pressure and inflammation.

Those who get too little sleep are also known to eat more and have unhealthier diets than those who get a good night’s rest. And those who sleep for too long are likely to be less active during the day.

The experts stressed that there is no firm evidence for what constitutes too much or too little sleep, but around eight hours is considered the ideal for most adults.

Dr Marie-Pierre St-Onge, of Columbia University in New York, said: “Patients need to be aware that adequate sleep is important.”