SMOOTHING on the sun cream and helping to rub it in those hard-to-reach places is part of beach etiquette.

But this week, a research charity suggested that by doing just that, we could be dramatically reducing its effectiveness.

Dr Rachel Haywood, a senior scientist at The Restoration Of Appearance And Function Trust, said sun cream would only work if applied in a thick "buttery" layer.

She said rubbing it in so you can't see it would cut protection against UVA light, which releases free radicals thought to cause skin cancers and premature ageing, to almost zero.

She said: "What we've found, and these are preliminary findings, is that if the cream is rubbed in such that it can't be seen anymore, then we find a reduction in free radical protection from 55 per cent to zero per cent at 2mg per centimetre squared."

But York GP Dr David Fair, of Yorvik Medical Centre, said people should not panic.

"It seems like this is a research study that hasn't been validated yet. It seems more like a suggestion rather than an absolute concrete bit of advice," he said.

"I suppose a lot of people are a bit confused about sun cream and think they can lie out in the sun indefinitely.

"You have to remember the factor is only as strong as it is supposed to be if you follow the instructions on the bottle and reapply it as recommended.

"Also, what is important for people to understand is that if they get a sun tan of any sort, it does imply powerful ultra violet rays have caused some damage.

"Tanning is your body's response to try and prevent further damage."

Although the choice of sun protection is now extensive, with foams, oils, lotions, sprays and even coloured creams on the market, Dr Fair does not think they have differing medical value. "I think it's just about convenience," he said.

Looking on the bright side, he said, people can benefit from the sun.

"There is a lot of evidence that exposure to sunlight is very beneficial for your mental health and also to prevent brittle bone disease," he said.

"We manufacture Vitamin D from sunlight, which is essential for the health of our bones. Some ethnic populations cover up too much and get osteoporosis through lack of sun exposure."

York chemist Elliot Goran, who runs pharmacies at Badger Hill and Dunnington, said he was unaware of the research.

He said: "People have got to make sure that they follow the instructions. Factor 50 or another high factor is only that high factor if people don't try and rub it down too much."

Being sun smart

  • Spend time in the shade between 11am and 3pm
  • Aim to cover up with a t-shirt, hat and sunglasses
  • Remember to take extra care with children
  • Then use factor 15 plus sunscreen
  • Also report mole changes or unusual skin growths promptly to your doctor