Removing the alcohol content of red wine does not reduce its health-giving properties, suggest experts.

In fact, the alcohol may actually shorten the benefits.

The study, published in the Amercian Journal of Clinical Nutrition, measured the amount of substances called catechins in blood plasma.

These are thought to reduce the risk of cancer and heart disease.

Volunteers were given either two glasses of normal red wine, and samples from which the alcohol had been removed.

They found no significant differences in the levels of catechins between alcohol drinkers and non-alcoholic counterparts.

And concentrations of catechins in plasma dropped more swiftly if alcohol was consumed.

Health claims

Catechins, also known as flavanoids, are believed to be protective against both coronary heart disease and certain types of cancer.

They can also be found in fresh fruit and vegetables.

They are thought to work by working as antioxidants, which protect cells against "free radicals", molecules which can cause damage.

The flavanoids are also thought to improve immune function.

Red wine contains more flavanoids that red or purple grape juice because the process of winemaking extracts more from the seeds and skins.

However, although the alcohol does not appear to contribute to the concentration of health-giving flavanoids, it is thought to benefit health in other ways.

It may be responsible for raising the levels of so-called "good cholesterol" in the bloodstream.

"Bad cholesterol", or low-density lipoprotein, is responsible for the clogging of blood vessels which causes heart disease - the more "good cholesterol there is, the less room there is for "bad cholesterol".

Another ingredient may widen the blood vessels and reduce the likelihood of clotting - both of which can improve cardiovascular health.

The benefits of moderate drinking - one or two glasses of wine a day - are thought to apply to people aged 33 or above.

Alcohol consumption above this level confers no extra benefit - and heavy drinking, particularly binge drinking can increase the risk of heart disease, and stroke