Chemicals found in tea could form the basis of a cream

Early tests on animals have suggested tea can stop ultraviolet light rays damaging the skin.

The researchers, who presented their findings to a meeting of the American Chemical Society, say drinking tea could give the same benefits as a cream.

But they say people would have to drink 10 cups a day to get the same effect.

Drinking tea may help, but you'd have to drink a large amount to accumulate in the skin, perhaps as many as 10 cups a day Dr Zigang Dong, University of Minnesota

Tea contains chemicals called polyphenols which the researchers from the University of Minnesota say appear to block the formation of non-melanoma skin cancer.

This type of cancer is the most common in the UK.

Official figures suggest there are around 59,000 cases diagnosed each year.

Sunblock prevents the skin absorbing harmful chemicals in UV light. But polyphenols - found in both green and black tea - appear to work after the skin is exposed to excessive sunlight.

The researchers found that polyphenols inhibit a chemical pathway involving an enzyme called JNK-2, or junk-2 which appears to play a key role in the development of tumours.

The scientists found levels of the junk-2 enzyme increased after the skin was exposed to sunlight and remained elevated in the skin of those exposed to excess amounts of sunlight.

Where junk-2 levels remain elevated, skin cancers are more likely to develop.

'Important step'

The researchers carried out tests on mice with skin cancer, where the animals were exposed to UV light.

It was found that putting the chemical directly onto the animals' skin decreased levels of the enzyme, which in turn seemed to block the skin's response to UV light.

Dr Zigang Dong, who led the research, said: "We feel this is an important step in improving the prevention of skin cancer.

"Topical application of certain tea polyphenols appears to block a key process that leads to skin cancer."

Dr Dong added a cream was likely to be better than drinking tea for its polyphenols: "Drinking tea may help, but you'd have to drink a large amount to accumulate in the skin, perhaps as many as 10 cups a day.

"It's easier to concentrate it in a cream form, and it's probably more effective."

He said the cream could be used alone or combined with sunscreen to help maximize cancer protection.

Human tests of the proposed skin cream could begin in a few years, he says.

'Be careful'

Dr Dong said other creams were already available but were unlikely to have undergone testing.

It is not yet known if the chemicals will also help tackle malignant melanoma, the least common but most deadly type of skin cancer.

Other research showed green tea might help prevent skin cancer because it has a high level of antioxidants, which destroy the free radicals thought to damage cell DNA.

Dr Elaine Vickers, science information officer at Cancer Research UK said: "A skin cream that blocks the activity of JNK-2 is an interesting concept.

"However, it will be many years before we know whether such a cream may be useful in preventing human skin cancer.

"At Cancer Research UK, we would advise people that the best way to reduce their risk of skin cancer is to be SunSmart.

"This means stay in the shade between 11am and 3pm, make sure you never burn, always cover up, remember to take extra care with children and use factor 15+ sunscreen."