NICE - sunscreen advice

Approaches to protecting skin

• skin should be protected from strong sunlight by covering up with suitable clothing, seeking shade and applying sunscreen
• sunscreen is not an alternative to covering up with suitable clothing and seeking shade, but it does offer additional protection. It can also be useful when other methods of protection are not available, but only if used liberally, carefully and repeatedly on all exposed skin

Sunscreen should:

• meet minimum standards for UVA protection (the label should have the letters 'UVA' in a circle logo). Preferably, the label should state that it provides good UVA protection (for example, at least '4-star UVA protection')
• provide at least sun protection factor (SPF)15 to protect against UVB

Because most people do not apply enough sunscreen it is probably helpful to make them aware that:

• the amount of sunscreen needed for the body of an average adult to achieve the stated SPF is around 35 ml or 6 to 8 teaspoons of lotion
  
  
• isunscreen is applied too thinly, the amount of protection it gives is reduced (for example, someone using too little SPF15 may only be achieving around SPF5 level of protection or less)
  
  
• using SPF30 sunscreen or higher may partially overcome problems with inadequate application. But it does not necessarily mean people can spend more time in the sun without the risk of burning
  
  
• sunscreen needs to be reapplied liberally, frequently and according to the manufacturer's instructions. This includes straight after being in water (even if it is 'water-resistant') and after towel drying, sweating or when it may have rubbed off
  
  
• if someone plans to be out in the sun long enough to risk burning, sunscreen needs to be applied twice to exposed areas of skin: half an hour before, and again around the time they go out in the sun. This includes the face, neck and ears (and head if someone has thinning or no hair), but a wide-brimmed hat is better
  
  
• water-resistant sunscreen is needed if sweating or contact with water is likely.

Reference:

• NICE (February 2016).Sunlight exposure: risks and benefits