SKIN  experts are warning people not to feel "invincible" in the sun just because they are wearing sun cream.

A groundbreaking study into the way UV radiation attacks the skin has revealed that long-lasting damage is not stopped by sunscreen.

Scientists at Manchester University and London’s Institute of Cancer Research carried out the world’s first molecular study into the way malignant melanoma, the deadliest form of skin cancer, is caused.

Their paper, published in the journal Nature, revealed that even highest grade SPF 50 suncream allows sufficient UV radiation through to damage the DNA in the skin’s pigment cells.

Stroud Dr Alistair Smith, of Locking hill Surgery, said: “For sun worshippers it is dangerous to rely on sunscreen alone in the hope of preventing skin cancer.

“There is no doubt that whilst high SPF products significantly reduce the risk of certain skin conditions, such as sunburn, this evidence suggests that malignant melanoma (the deadliest form of skin cancer) may not be prevented, even by diligent application and regular use.

"Indeed the false sense of security provided by the use of sunscreen may encourage people to stay out in the sun for longer, with the potential for increased skin damage.

“The best way to avoid trouble, especially for people with known risk factors for melanoma (such as pale skin, lots of moles, or a family history of skin cancer) should always use high-factor sunscreen in combination with other preventative methods, such as wearing appropriate clothing and staying in the shade when the sun is at its hottest (between 11am and 3pm).”

Dr Julie Sharp, of Cancer Research UK, which funded the study, said: “People tend to think they’re invincible once they’ve put it on and end up spending longer out in the sun, increasing their overall exposure to UV rays.

“This research adds important evidence showing that sunscreen has a role, but that you shouldn’t just rely on this to protect your skin.”

Malignant melanoma is the fifth most common cancer in the UK, with more than 13,000 people diagnosed with the disease every year.

The scientists found that sunscreen could not stop solar radiation causing a mutation in the skin’s ‘guardian gene’ which produces proteins that protect against UV.