It may be cold, wet and grey - but you still need to slather on sun screen every day

By Professor John Hawk

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It’s another bank holiday weekend and in Britain we’re all too aware that can mean dull, overcast skies.

The thought of reaching for the sun cream might be one of the furthest things from your mind but, as an expert in the damage caused to the skin by harmful rays, I believe we need to be slathering on high-protection lotion every day.

Before you scoff, read on .  .  .

Screen yourself: Come rain or shine, applying sun protection ought to be part of your every day routine

Screen yourself: Come rain or shine, applying sun protection ought to be part of your every day routine

The weather has been poor lately – surely I don’t need to wear sun protection now?

Now is the time to be vigilant. Damage to the skin is caused by UV rays and they are at their strongest in June, when the Earth is tilted most towards the sun. The potential for damage is not related to the temperature outside.

 

But the only sunlight I see is when I pop to the shops during my lunch break.

You don’t need sun screen when you’re going to work in the early morning or returning home at 6pm because UV rays are weaker at those times. But between March and October, lotion should always be used between 11am and 3pm, when the sun is at its highest.

This applies even if you are just popping to the shops or hanging out the washing in the garden, because the risk starts the moment you step outside. Two minutes spent outside may produce only a little damage, but all these little exposures add up over a lifetime.

UV had enough: A glimpse of sun every day - five to ten minutes - will get you your daily dose of UV rays

UV had enough: A glimpse of sun every day - five to ten minutes - will get you your daily dose of UV rays

What kind of risk is there from hanging out the washing?

If you have very fair skin and spend 30 minutes outdoors on any single occasion in June without sun screen, the increased cancer risk is probably the equivalent to smoking a cigarette.

Most light-skinned Caucasians get pre-cancerous patches in their 50s or 60s, while those with very fair skin see them in their 40s. Using sun screen reduces the cancer risk dramatically.

So if I sat in the park this weekend – even under grey skies or rain clouds – I would burn?

Yes, you would. Cloud does not absorb UV very well, and neither does rain. If the cloud is low it will reduce the UV, but you’d still burn – it would just take about twice as long.

What about increases in people suffering a deficiency in Vitamin D, and of the rise in rickets among children – don’t we need to sit in the sun?

Latest research has found that sun lotion may not hinder Vitamin D production in the skin as much as first thought.

Researchers followed a group of people sunbathing all day in the Canary Islands over the course of a week and found that those who applied high-protection cream still produced some Vitamin D.

Yes, we need UV exposure, but just five to ten minutes daily on your face and hands without protection is enough.

There has been an increase in Vitamin D deficiency but it remains rare and is linked to other factors – for example, a patient may be confined to bed for a long period.

How much sun screen  should I use?

The average adult needs 3ml – two-thirds of a teaspoon – on each arm and also for the face and neck, and 6ml for each leg, for the front of the body and also for the back. If you know you’re going to be outside for a long time, put it on before and preferably again a few minutes after going into the sun to ensure all areas are definitely covered. You should reapply lotion every two to three hours.

I’ve been told to throw away old bottles – do they really go off or is that just a marketing con?

Sun cream will usually last two years – if it has gone off, it will become runny or clumpy. There is no difference in effectiveness between cheap and expensive products as the sun-protection factor must be made according to legal requirements.

 Do I need protection if I’m sitting in the car or conservatory?

While glass stops UVB rays, it lets through UVA light, so you can still get some skin damage and burn eventually, though it will take ten times longer. Even shade will only protect you if you can’t see much blue sky. UV rays bounce around off atmospheric molecules, so they come from every angle – whereas visible sunlight doesn’t.

The comments below have not been moderated.

wow I read the article and laughed at the basic science that was in it, then read the comments and laughed even harder. 'So even sitting under rain clouds is a big risk? Sorry, I don't believe you.' 'silly advice' the sun is extremely dangerous to all of us, some of the figures in this article may be distorted, but what it's generally trying to say is the rays of the sun are harmful, and believe it or not they can penetrate clouds and it does effect your skin.

Click to rate     Rating   7

Professor John Hawk this article contains so much disinformation I do not know where to start. Using sun screen does not reduces the cancer risk, it increases the cancer risk. This is because sun screens contain many toxic chemicals some of which are carcinogenic. The increase in skin cancer rates correlates with the increase in the use of sun screen. - Michael Haymar , Oxford UK, 27/5/2013 16:23 Who do I believe? A distinguished dermatologist who has published innumerable scientific papers, especially in the field of photobiology, or some guy called Michael that has no proper evidence to support his theories. Not hard really, is it? :-)

Click to rate     Rating   6

Rubbish!!! Vitamin D deficiency is rife, even in Australia, and not just in people confined to bed.

Click to rate     Rating   30

Great story for trying to flog all the tubes of sun screen before their self by date! Are you getting a share of the profits DM?.

Click to rate     Rating   14

this how children are ending up with vitamin d deficiencies. silly advice

Click to rate     Rating   28

So even sitting under rain clouds is a big risk? Sorry, I don't believe you.

Click to rate     Rating   24

Professor John Hawk this article contains so much disinformation I do not know where to start. Using sun screen does not reduces the cancer risk, it increases the cancer risk. This is because sun screens contain many toxic chemicals some of which are carcinogenic. The increase in skin cancer rates correlates with the increase in the use of sun screen.

Click to rate     Rating   9
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