High cholesterol increases the risk of heart disease

But the National Diet and Nutrition Survey of 2,000 people suggests the figure may be even higher for over 50s.

It found 59% of men and 75% of women between the ages of 50 and 64 have too much cholesterol in their blood.

The fatty substance clogs up the arteries and is a major cause of heart disease. Experts believe poor diet and a lack of exercise is to blame.

A study, published last month, suggested many Briton's are confused when it comes to cholesterol.

It found that just 5% know that high cholesterol can increase the risk of heart disease.

Drug study

The findings come as another study backs up the case for using statins to treat high cholesterol.

Researchers at the University of Leeds have found that statins, which are taken by more than a million people in the UK, may also keep the heart healthy.

The study, published in the journal Cardiovascular Research, found statins act directly on the heart and prevent the structural damage that can cause disease.

In a failing heart, structural cells or fibroblasts that shape it can multiply and move around.

This stops the heart from working as effectively as it should and causes permanent damage.

"Statins stop this process," said Dr Karen Porter, who led the study.

Meanwhile, the National Diet and Nutrition Survey, which was carried out for the Food Standards Agency, also confirms that more and more people are becoming obese.

It found that 25% of men and 20% of women are now classed as obese.

This compares to 8% and men and 12% of women in 1987, when the survey was last carried out.

Almost 1,700 people who took part in the survey also kept an activity diary for a week taking note of how much exercise they did.

Researchers found that just 35% of men and 26% of women did enough physical exercise.

The Department of Health recommends that adults do at least 30 minutes moderate or above activity on five or more days a week.