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Are we protecting ourselves properly? How to apply suncream this summer

Posted by Charlotte Maude on Thu, Jun 13, 2019 @ 11:30 AM

adult-architecture-beautiful-1537168Summer is almost here! And with it’s arrival comes the annual search for the suncream bottle. While the message has got through to most of us about the importance of using skin protection when in the sun, surveys reveal that many of us aren’t using products correctly, and are consequently putting ourselves at increased risk of skin related conditions, and most worryingly, skin cancer. Getting sunburn just once every 2 years can triple your risk of skin cancer and yet, according to skin experts,  9 out of 10 cases of melanoma, the most serious type of skin cancer, could be prevented, by avoiding sunbeds and using adequate sun protection.

We’ve written about the effects of heatstroke before and with the increasingly hot temperatures around the world, it is critical that we protect ourselves from this condition. You can read that post for more information on heat stroke, heat exhaustion, and the effects of being out in the sun on the body. In this blogpost, however, we want to explain the confusion that exists around the use of sun protection creams. How much should we apply and how often? Sunscreen or sunblock? UVA protection or UVB? Which SPF? There are so many factors (no pun intended) to consider, and we’ll go over them all, also uncovering some of the myths about sun protection and the potential dangers when we don’t use suncreams properly.

What is sun tan?

To start with the basics, lets analyse exactly what happens when we tan. After our skin has been exposed to sunlight, pigment cells called melanocytes produce more melanin in an attempt to absorb UV radiation and, as a consequence, the skin becomes darker. The problems start when too much UV starts to damage the DNA of the skin cells. If enough DNA damage builds up over time, it can cause cells to start growing out of control, leading to skin cancer. So the bottom line is tanned skin equals damaged skin, and this can be dangerous if it occurs regularly or intensely. Caucasian skin is more at risk of damage than darker skin types, where melanin production is continuous, meaning that as the cells are constantly protected by the melanin, the incidence of skin cancer is much lower.

Sunscreen or sunblock?

These are often used interchangeably but are actually two very different types of sun protection. Sunscreen offers a chemical defence, absorbing the sun’s rays before they reach and damage the dermal layers of our skin. As sunscreen has to be absorbed into the skin to work, it should be applied 20 minutes before going into the sun. Conversely, sunblock sits on top of the skin so can offer immediate protection, acting as a barrier and reflecting the suns rays away from the skin. Both types are effective in protecting your skin, so according to the Skin Cancer Foundation, you should base your choice on which product works best for you. If you have sensitive skin, or suffer from conditions such as rosacea or certain skin allergies, you may struggle to tolerate the chemicals found in sunscreens and are more suited to the mineral-based sunblocks which use zinc oxide and titanium dioxide. However, a sunblock tends to have a thicker, more opaque consistency that makes it harder to spread over the body, meaning it can often be seen after application which is unappealing to many.

UVA or UVB?

In a nutshell – both. UV radiation from the sun, which is what causes the damage to our skin cells, is transmitted in three wavelengths: UVA, UVB and UVC. As UVC doesn’t penetrate the earth’s atmosphere, we only need to worry about the first two. UVA affects the elastin in the skin, leading to wrinkles and sun-induced premature ageing, as well as skin cancer. It can pass through glass and penetrates the skin more deeply than UVB. UVB is responsible for the majority of sunburn cases which have strong links to malignant melanoma and basal cell carcinoma, the 2 most common types of skin cancer. Some creams are now showing a UVA* rating which indicates the percentage of UVA radiation absorbed by the sunscreen in comparison to UVB.

What SPF should I use?

This stands for Sun Protection Factor, but strictly speaking should be called Sunburn Protection Factor, as the number refers primarily to protection against UVB rays and potential sunburn rather than UVA rays. Rated on a scale from 2 to 50+, it works on the theoretical basis that if it takes 20 minutes for your unprotected skin to start turning red, using an SPF of 15 allows you 15 times longer in the sun before your skin starts changing colour. However, most dermatologists would argue that spending this amount of time in the sun without any protection is still too long. SPF’s of 30 plus are recommended as a satisfactory form of sun protection combined with shade and clothing and will block out 97% of rays.

How should I apply suncream?

Armed with the knowledge above, we should in theory be keeping ourselves safe. Unfortunately, there’s a lot of misunderstanding about how to use suncreams properly, so here are some do’s and don’ts.

Do

  • re-apply regularly - One application a day just doesn’t do it. Ideally, you should be layering on the SPF every 2 hours. Remember, a 30 SPF rating means you are covered for 30 times the amount it takes for you to burn without any protection, so to be safe and covered, you should re-apply within this time.
  • re-apply after swimming - Non water-resistant creams will completely disappear after a swim or shower, so you need to re-apply suncream immediately. Even water-resistant creams lose some of their efficacy, so try to reapply more frequently if you’ve been in or under the water
  • wear it when it’s raining - Just because it’s grey and drizzly doesn’t mean you can’t burn. 80% of UV rays still come through on cloudy days. Whatever your local climate, you should ideally use an appropriate suncream year round, or at the very least, a moisturizer with an SPF.
  • wear enough - Probably the most common mistake is not using enough suncream. You should ideally use a coin-sized amount for your face and a minimum of 2 tablespoons, roughly the size of a golf ball, for your body. Research shows that most of us use around 25% of the amount of suncream we should. Using sprays makes this even harder to measure, so if using a spray, ideally use a coloured one that shows the areas you’ve covered
  • apply when you’re indoors - Most people assume they’re protected when behind glass, but we’re not. Rays can penetrate, as shown by a recent study, which found that melanoma patients were more likely to have the disease on the left side of their body if they were in a left-hand drive country and vice versa

Don’t

  • miss a spot - Make sure you apply cream to the tricky spots like the mid-back and backs of your legs. Just because you might be lying on your back most of the day doesn’t mean these areas won’t be exposed. The most commonly missed areas are your toes, feet and soles of your feet, your underarm, back of neck, ears and inner upper arms, eyebrows, and hairline
  • wait until you’re in the sun - If you’re using sunscreen, don’t wait until you get outside to apply it. As we mentioned above, sunscreen works via a chemical reaction which isn’t immediate. You need to apply sunscreen 20-30 minutes prior to exposure. This doesn’t apply to sunblock which works with immediate effect.
  • ignore your lips -  These are just as vulnerable to UV rays as the rest of your body. Use a lip balm with an SPF and apply more regularly as talking, eating and drinking will remove it more quickly
  • assume you’re immune -  those with darker skin are less likely to burn and have slightly lower risks of skin cacner, but that doesn’t mean you’re immune. While you will have more natural protection, you should still apply an SPF of at least 30 regularly if you want full protection
  • use a cream that only offers UVB protection - That counts even if it has a high SPF. UVA is just as important. Many creams now offer both UVA and UVB protection and are labelled ‘broad spectrum,’ so make sure you’re covered
  • keep it for too long - A bottle of suncream isn’t for life: depending on the brand, most suncreams will lose their effectiveness after 2 years. That’s made even earlier if they’re exposed to UV light and heat which encourages them to degrade faster
  • leave it off if you’re in the shade - While lying in the shade under a tree or parasol will give you some protection, don’t assume you don’t need suncream. Up to 34% of rays will penetrate a beach umbrella and while you may not show signs of obvious skin damage, you’re still getting UV exposure
  • use your clothes as suncream - Clothes won’t actually provide much protection. If you hold the fabric up to the light and can see through it, the sun can penetrate it too. Many patients have melanomas on their backs which have had less exposure than arms and legs, but were not protected with suncream underneath their clothes

Could I have skin cancer?

Screen Shot 2019-06-13 at 15.22.35

While the effects of sunburn are all too easy to spot and feel, skin cancer is less obvious. If you notice any unusual or persistent changes to your skin, go to your doctor. Unusual skin markings can have many causes, but the earlier skin cancers are detected, the easier they are to treat. You should visit your doctor if you notice any of the following to a mole, freckle or just a normal patch of skin:

  • An uneven edge with a jagged border
  • An asymmetrical shape
  • An uneven colour
  • A new growth or sore which doesn’t heal
  • A spot or mole which itches or hurts, bleeds or scabs

If you’re any doubt, try using the Isabel Symptom Checker and discussing the results with your doctor.

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