This picture is for illustrative purposes only. Image Credit: Getty

These days, more and more stars are gracing red carpets looking perfectly porcelain. Anne Hathaway, Cate Blanchett, Kristen Stewart – there’s not a hint of bronze or a whiff of fake tan on these leading ladies. If you ask almost any celeb what the secret is to keeping a youthful, wrinkle-free complexion, the answer isn’t Botox – it’s an SPF.

Celebrity dermatologist Albert M Lefkovits revealed that although they don’t hide away from the sun completely, Hollywood and Bollywood starlets are super careful when it comes to sun protection. “They don’t live in a cocoon to avoid rays, but they also don’t lie out in the sun for hours and, believe me, they are always putting on sunscreen” he says.

And we should be following their example and doing everything we can to avoid the effects of the sun, be it with large hats, cover-ups, or the use of a sun cream. We are constantly being barraged with campaigns telling us to protect ourselves from harmful rays, wear a high SPF and to reapply it often.

Even Baz Luhrmann’s old-school 90s’ hit, Everybody’s Free (To Wear Sunscreen) told the world “If I could offer you only one tip for the future, sunscreen would be it” – and it seems as though he was on to something. But are you making the most of your sun cream, and do you really know what the number on the bottle means? Well, we’ll tell you, as it’s time to get SPF savvy…

Know your numbers

SPF stands for Sun Protection Factor, and the numbers were developed in 1962 as a way of measuring a sunscreen’s effect against UVB rays. They show how long you can stay in the sun wearing a sunscreen without burning. For example, if you normally burn after 10 minutes in the sun, an SPF15 will give you 15 times that – or 150 minutes without burning.

For an easy way to work out what SPF you need and how long it will protect you, use this simple equation: minutes to burn without sunscreen x SPF number = maximum sun exposure time.

Zain Shaikh, brand manager at Hawaiian Tropic Middle East, says one of the most common misconceptions is when people think, “If I apply a lotion with an SPF8 and then put an SPF15 on top, I’m actually wearing an SPF23”.

As Zain says, “SPF numbers don’t add up the way you might think. Using an SPF8 and an SPF15 together won’t allow you to remain in the sun 23 times longer than without protection. You need to determine how long you’ll be in the sun, along with your skin type, and choose the appropriate SPF level for you.”

There’s also the issue of high-factor SPFs. We’re talking 50+, with some brands going so far as to claim that theirs are SPF100. This instantly makes you think you are receiving 100 per cent sun protection, right? Wrong (it protects against 98.5 per cent of UVB rays, just 1.5 per cent more than a factor 50). And this is the deadly mistake that many of us are making.

High-factor sunscreens give a false sense of security, resulting in less reapplying, more time in the sun, and more burning and harmful damage.

To Dr Julie Sharp of Cancer Research UK, this is a major concern,”People tend to think they’re invincible once they’ve put it on and end up spending longer out in the sun, increasing their overall exposure to UV rays.”

The US Food and Drug Administration has even proposed a ban of labels higher than SPF50+, stating that they are “inherently misleading”. There is no such thing as a 100 per cent protective SPF, nor is it the case that an SPF30 is twice as effective as an SPF15.

In fact, according to dermatologist James M Spencer, MD an SPF15 blocks 94 per cent of UVB rays, whilst an SPF30 blocks 97 per cent. “After that, it just gets silly,” he says.

Excessive exposure to UV radiation from the sun damages the skin’s cellular DNA and produces genetic mutations, which is why both the US Department of Health and Human Services and the World Health Organisation have identified 
UV rays as carcinogen – a cause 
of skin cancer.

This comes as no surprise; it’s a fact that’s constantly drummed into us via the media, health experts and beauty brands. But just because you’re slapping on the SPF doesn’t mean you aren’t at risk, as not all sun creams protect you from both harmful types of UV rays.

We look to an SPF as a number we rely on to tell us how long we can stay in the sun before we start to burn and cause damage, and how high a level of protection we are receiving from our sun cream or skincare product. What it doesn’t tell you is that this number refers to UVB rays only – not UVA.

It’s obvious when UVB rays are causing damage; they’re the ones that lead to sunburn and redness as they are absorbed by the top layers of skin. And although UVBs are arguably more harmful and are the biggest cause of malignant melanoma skin cancer, the ozone layer absorbs most of them before they reach us, which means that 90-99 per cent of what hits us are UVA. UVA rays are constantly present come rain or shine, and they are the ones responsible for causing sun damage on a cloudy day.

Yes, that’s right, they can get through clouds! They penetrate far deeper into the skin, damaging cells and tissue way beneath the surface, resulting in faster ageing, sunspots, wrinkles and skin that resembles an old leather sofa. Nice.

So next time you reach for that tropical-smelling bottle, make sure it protects against UVA and UVB rays, or is a broad spectrum SPF (it will say so on the label), which combines chemical and physical blockers to keep both 
UVA and UVB rays at bay.

There are also increasing concerns surrounding infrared rays, which have always been there but until recently weren’t factored into sun protection. After a 2009 German study, it was revealed that the spectrum of sun damage goes further than UVA and UVB rays and that infrared radiation is also responsible for releasing free radicals and accelerating the ageing process. With infrared rays representing more than 50 per cent of the solar spectrum (compared to 0.6 per cent for UVBs), modern sun protection products now pack even more of a punch.

Dr Olivier Doucet, Lancaster Laboratories’ vice-president of research and development, strongly believes that infrared protection is a vital part of an SPF and has been a key player in incorporating new technology into the brand’s sun products. “Infrared rays create a strong increase in the skin’s temperature, by about 6 or 7°C,” he tells us. “By way of comparison, the body would not withstand a temperature rise of this kind. This has a very significant impact on the skin’s metabolism.”

Moreover, infrared rays penetrate more deeply than UVA rays into the layers of the skin, where they cause damage to the skin’s architecture and the extracellular matrix (the component of body tissue that supports cells). These rays are particularly involved in loss of firmness and have a deleterious action on DNA, the elastin fibres and the genes responsible for renewing collagen fibre reserves (meaning skin ages faster and loses elasticity and firmness).

The amount of skin damage caused by infrared rays has yet to be determined, but according to Senior Researcher at Johnson & Johnson, Michael Southall, PhD, “traditional sunscreens, which only block UV, don’t protect us from the sun’s total oxidative toll.” This is when oxygen interacts with cells, leading to free radical damage, cellular mutations and DNA disruptions – a major cause of ageing, cancers and skin problems.

According to Dr Hala Fadli, specialist dermatologist in the UK and Dubai, we should all be wearing an SPF all the time. “Sun blocks should be used throughout the year to protect our skin from skin cancer, sun damage, and premature ageing of the skin. It is proven that skin cancer in adults 
is due to sunburn during childhood. The longer the exposure to sunlight, the higher the risk of developing skin cancer.”

Even if you’re sitting in the shade, don’t be fooled into thinking you’re covered, as according to the experts at Bioderma, “shade offers protection against the sun’s direct rays but not against the sun’s rays reflected off the ground (grass reflects 3 per cent of the UV rays hitting it, sand between 5 per cent and 25 per cent, and water 5 per cent to 90 per cent), and not against the sun’s rays diffused by particles suspended in the atmosphere (at midday, 30 to 50 per cent of UV rays on the skin are rays diffused by atmospheric molecules).”

One of Zain Shaikh’s top tips is to “wait 20-30 minutes after applying your sunscreen before going outside, so the UV filters have time to soak into your skin and form a protective layer”.

And don’t forget to reapply, especially after towel drying, swimming or excessive perspiration.

Of course the sun isn’t all bad. Our bodies don’t produce their own vitamin D, which releases endorphins, helps maintain a healthy immune system, keeps bones strong, can lower blood pressure, protects against heart disease and improves muscular function. So we need it from sunlight.

Dr Fadli says the sun can offer a host of benefits. “Sun exposure has many positive effects. Firstly, it is responsible for the body producing vitamin D, which is crucial for prevention of rickets. Secondly, some skin conditions can improve with sun exposure, such as eczema and psoriasis. Sun exposure can also help treat depression.”

So the sun can be your friend and 
not your enemy – just make sure you’re SPF savvy… and wear a hat.