London: A sunscreen based on caffeine could help protect against skin cancer and also keep your wrinkles at bay, scientists have claimed.
The appealing thought comes from American scientists who have shown that caffeine triggers the death of UV-damaged cells, while leaving healthy ones unharmed.
To test the idea that caffeine provides protection by interfering with a skin protein called ATR, the researchers at from Rutgers University in New Jersey genetically-engineered mice so that they made much less ATR than usual.
They put the animals and normal mice under UV lamps and found that those low in ATR took longer to develop skin cancers.
After 19 weeks, the GM mice had 70 per cent fewer tumours and the cancers they did develop were far less likely to have penetrated the skin, allowing them to use the bloodstream to spread through the body, the researchers said.
According to the researchers, cells need ATR to repair damage and if there isn't enough of it, they self-destruct, nipping any cancer in the bud. Caffeine lowers levels of ATR, pushing UV-damaged cells towards suicide.
The finding explains past studies which credited drinking caffeinated - but not decaffeinated - tea and coffee with warding off non-melanoma skin cancer, the researchers said
Around 100,000 cases of this type of non-melanoma skin cancer are diagnosed every year in the UK but is much more easily treated than the less common but more deadly malignant melanoma skin cancer.
Despite their results, the researchers said that people shouldn't start consuming vast amounts of tea or coffee just so that they can lie out in the sun.
The finding could be used to create a caffeine-based sun cream, they said.