UK advice on sun screen strength is 'too low'

1st June 2010 - The strength of sun screen recently recommended by the National Institute for Health and Clinical Excellence (NICE) is far too low and "not in the interests of public health," warns the latest edition of the BMJ's Drug and Therapeutics Bulletin (DTB).

NICE recommends sunscreens with a sun protection factor, or SPF, of 15 as sufficient to prevent sunburn and the subsequent potential risk of skin cancer, but the DTB editorial believes NICE should have recommended products labelled with an SPF of 30.

The DTB says on the face of it the NICE advice seems reasonable, but the problem is that a sunscreen with an SPF of 15 only delivers that degree of sun protection if it is applied to the skin at a thickness of 2mg/cm2, which is how manufacturers apply the standard test for SPF.

"In reality ... people using sunscreens typically apply much less than this and get no more than half, at best, of the protection indicated by the labelled SPF," says DTB in its editorial on the subject. It points out that in order to meet the NICE recommendation, a single application for an adult would require 35 ml of sunscreen, and if applied every two hours would use up a standard 200 ml bottle every two to three days - both expensive and impractical.
It argues that the conditions under which sun creams are tested should be changed to more accurately reflect the way people use them.

'Blunder'

"Products labelled with an SPF of 30 (together with a four or five star rating to indicate broad spectrum ultraviolent screening effect) will more reliably deliver adequate sun protection to most people who use sunscreens and would be sufficient to prevent sunburn under most circumstances. We believe this is what NICE should have recommended," says DTB.

Dr Ike Iheanacho, DTB editor comments in a press statement: "In DTB's view, NICE's recommendation to use sunscreens with an SPF as low as 15 is a blunder that overlooks the key evidence and is not in the best interests of public health. This advice needs urgent review and correction."

Response from NICE

Professor Mike Kelly, Director of the Centre for Public Health Excellence at NICE said in a statement: "The NICE guidance referred to was not an assessment of which sun protection factor is optimal, but rather was concerned with the most effective ways of reducing skin cancer in England through provision of information, supply of resources and changes to the physical environment. It also sought to make clear that sunshine can be good for us, in that it provides a good source of vitamin D, and the opportunity to be physically active out of doors.

"We felt it was important, in producing this guidance, to maintain a balance - recognising on the one hand the very real dangers of skin cancer, but also remembering on the other hand that we should not extrapolate from research carried out in much hotter, sunnier climates than our own.

"We commissioned an expert report on the use of sunscreen in preventing skin cancer in England. According to this evidence, which was presented to the committee, SPF 15 should be sufficient as long as it is applied adequately. However, the guidance also acknowledges that to take account of people not applying sufficient quantities of sunscreen, SPF 30 was also recommended in an expert paper."