You might not be applying as much sunscreen as you should.
Most people know they should be reapplying sunscreen regularly if they're out in the sun for a long time.
The new NICE guidelines say sunscreen should be "reapplied liberally, frequently and according to the manufacturer's instructions". You also need to make sure you reapply it after being in the water – even if it claims to be water-resistant – and after towel-drying or sweating, or if it might have rubbed off.
And you probably know that you should be using more than you actually do.
But there's a bit in the guidelines that you might not have been aware of.
According to NICE:
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.
Yes, you read that right – you should be applying sunscreen twice. Before you go out, and then again as soon as you're in the sun.
The guidelines also clear up some common misconceptions about sun exposure.
They say that even if it's cool or cloudy, it's possible to get sunburnt at midday in the summer. And a "base tan" protecting you from harm is untrue – the skin damage resulting from any tan you have outweighs the slight protective effect.
"A suntan is a sign that skin has already been damaged," according to the Journal of the American Medical Association. "And tanned skin can continue to be damaged when exposed to UV rays."
There's even more sad news for everyone living in the UK.
The guidelines state that it's not possible to get enough Vitamin D from sunlight in the UK between the months of October and March. That's six months, aka HALF OF THE ENTIRE YEAR.