Even the construction workers care about the UV index in Chile! The health and safety people deserve a medal.

Now that we have passed the summer solstice and are officially in summer, it seemed appropriate to write a bit about sunscreen. Even in Scotland the UV index can get dangerously high - recently I missed getting a picture of my other half’s blistered skin after a weekend’s trip to Ben Nevis. He’s one half Sri Lankan so has some natural protection, but clearly needed to either slap sunscreen on or wear protective clothing!

There seems to be an idea circulating at the moment that more is better so far as SPF is concerned. Protecting your skin against UV radiation is important to prevent signs of photo damage (wrinkles, patchy pigmentation and the like) and skin cancer, but it isn’t true that in terms of SPF you get more benefit from a higher value.  The incorrect use of sunscreen can mean you are not getting the protection you think you are.

I have always been a big advocate of wearing sunscreen, ever since I was in college and saw first hand what a difference it makes.  Growing up in South Africa, even though I did believe that taking care of your skin made a difference, I still thought that people just looked a certain way as they got older and there wasn’t that much you could do to dramatically change the effects of the passage of time.  That all changed in my second year, when I was going through a consultation with a facial client and nearly fell off my chair when I discovered she was ten years older than I would have placed her at.  It turned out that she had been wearing sunscreen on a daily basis since the age of 17, which effectively ended my love affair with trying to get a tan.

What does the term “SPF” mean exactly?

The SPF, or sun protection factor, is the term used to indicate the level of protection against UVB rays which result in burning.  So if you take 5 minutes to burn when not wearing sunscreen, when wearing an SPF 20 you will be able to stay in  the sun without burning for 5×20 minutes or a bit over 1 and a half hours.  During this time you would probably be getting a tan.  Why is this?  Because the SPF is not an indication of protection against UVA, and it is this spectrum of rays which penetrates to the dermal layer creating a tan, and all the damage listed above. This is why you can tan without burning when using a sunbed – hopefully it is clear when reading this that sunbeds are not a “safe” way to get a tan. An interesting statistic released by a survey done in the US was that the incidence of sunbed related skin cancer was double that of that of smoking related lung cancer. DOUBLE!!!  UVA star ratings are becoming more and more common now so be sure to look for both when shopping around.

How do sunscreens work?

Sunscreen ingredients work in one of two ways – reflective (zinc and titanium dioxide) or absorptive (the rest).  The reflective type sits on the surface of the skin and is what can give you an undesirable whitish appearance (although modern technology has mostly overcome this) while the absorptive type penetrates the skin and absorbs UV rays, converting energy into heat and getting broken down in the process. The unfortunate side effect of this process is the production of free radicals which will now be present under the skin’s surface.

IMPORTANT NOTE:  This problem can be dealt with by using antioxidant products alongside your sunscreen – it does not mean sunscreens are dangerous, but it helps to be aware of this fact.

Isn’t a tan healthy, though?

In short, not necessarily.  Although there are definite benefits to getting out in the sun, vitamin D production and mood improvement being high up on the list, what is going on in the skin when the melanocytes kick into action and release more melanin than normal is the skin is doing it’s best to protect itself from the harmful effects of UV radiation. That’s it.  That’s all a tan is. The melanin granules collect on the outermost side of the nucleus, shielding it from UV because the free radical cascade that results can do DNA damage which means that when the cells divide, they don’t replicate themselves perfectly.  At the very least this results in accelerated aging, and at the very worst it leads to skin cancer.

All that being said, it doesn’t mean that you need to avoid all sun exposure and use a high factor sun screen on a daily basis if you tend to spend the majority of your time indoors.  While it is true that a tan is your skin trying to protect itself, it is also an important part of its defence system and if there is no stimulation of the melanocytes for an extended period of time they start to lose their ability to respond quickly when they are exposed, leading to a reduction in your natural protection.  It may also be that vitamin D production – 80% of which is formed in the skin as a result of sun exposure – can be affected, leading to problems such as osteoporosis down the line.  How sunscreen can affect your vitamin D production is actually, like pretty much everything involving the skin, dependant on a variety of factors. The amount of UV exposure needed to maintain vitamin D levels depends on the time of year, location, skin type, day-to-day activity and individual circumstances.  Click the link below for more detailed information on sunscreen and vitamin D production – note that sunscreen is not needed when the UV index is 3 or below (this is easily checked online) provided that you are using the correct skin care. During the winter in the UK the UV index rarely goes above 4, so if you are using a product which contains vitamin A this will give you sufficient protection and an additional sunscreen won’t be required for occasional exposure. Of course, this doesn’t apply if you are on a ski slope!

http://www.sunsmart.com.au/vitamin-d/how-much-sun-is-enough

My skin tans easily and I never really burn, do I still need sunscreen?

Yes, if you want to avoid getting pigmentation problems when you get older.  Even if you aren’t at risk of developing skin cancer (and skin colour is no longer the determining factor, the red-head gene can still be present in your makeup if you have dark skin), the melanocyte is still damaged by prolonged exposure.  It is recommended to wear a low SPF containing antioxidants such as beta carotene and vitamin C, which slow down the production of melanin. I routinely have clients in their mid 30’s coming in to treat pigmentation that has “suddenly” appeared - there’s nothing sudden about it, it’s been forming for the past 35 years…

My skin is really fair, isn’t it better to wear a very high factor sunscreen?

Not always.  As has been said previously, the SPF only refers to the UVB protection but doesn’t take into account UVA exposure, and it’s UVA which causes the damage.  While you can still reapply every hour, people tend to get complacent because they aren’t burning.  So for normal conditions where you are in a situation where you are able to reapply regularly, you only need use around factor 20 – 30.  I will use a factor 50 if I am rock-climbing, as I might not be able to slap on another layer and I’d rather avoid burning, but then will apply an antioxidant product later to mop up the free radicals which will have formed.

Size matters

In order to get the level of protection advertised you need to be putting the right amount on, which is normally 2mg/square centimetre or about the size of a 50p piece for an area the size of the face. Many people put the bare minimum on, and think they are getting the full SPF – this is particularly true when relying on makeup or moisturiser, to get the advertised protection from applying foundation would mean you would have to really cake it on.

HOW TO ENJOY THE SUN SAFELY

1. Wear a lower factor sunscreen (SPF 20 to 30) and reapply every hour.

2. Make sure your sunscreen includes physically reflective titanium dioxide or zinc oxide as part of the protection.   This not only protects your skin but protects the absorptive sunscreen components, lessening the production of free radicals.

3. If you are wearing a chemical sunscreen try and find one containing antioxidants, or apply a product containing antioxidants over the top to protect the absorptive components as well as mopping up any free radicals formed.   Beta carotene is a very good antioxidant for this purpose.

4. Pre- and post care of the skin with Vitamins A, C and E as well as a cocktail of antioxidants ensures that the skin is in the best possible health to get the maximum benefit with minimum damage from your time in the sun.  Taking antioxidant food supplements such as lycopene, starting a few weeks before your holiday and then throughout your stay, gives you a superior protection internally that boosts everything you are doing externally.  I’ve really seen great results with this when treating a client with pigmentation.  Normally when treating this condition, no matter how diligent you are with products, hat and sunglasses there is a darkening of the patches during a sunny holiday.  This client had no visible change afterwards which was a record first for me!

5.  Put on a generous amount of product, not the thinnest smear you can manage.

6.  As has been said many times before, don’t lie out in the sun between 11am and 3pm, and wear a hat.

A note on re-applying

If, like me, you thought that if you get two hours protection with one application of sunscreen then if you reapply at the end of two hours you will get a further two hours of protection, think again.  Here is how it breaks down:

Take the example of a person who takes 4 minutes to burn when not wearing sunscreen, who applies an SPF of 30.  This will give them 120 minutes of sun exposure before reaching 100% Minimal Erythema Dose (MED), the dose of UV which gives you sunburn. Should they reapply another dose of SPF 30 at the halfway mark 60 minutes, this will not give another 120 minutes of protection as 50% of the MED will already have been received.  The re-application acts as a booster to the initial application, meaning that when the 120 minute mark is reached they will have received approximately another 25% of their MED. Should they not reapply at this time, they will reach 100% MED at around 150  minutes. If they do reapply at the end of 120 minutes the final 25% will be used up at approximately 165 minutes from the initial exposure time.  So to summarise, reapplying twice during 120 minutes only gives you about 45 minutes extra exposure time.

What to avoid

There are some sunscreen ingredients which are still widely used but really should be avoided at all costs.  One of these is oxybenzone, which is a quite common chemical sunscreen that has been identified as a photosensitiser.  It also creates free radicals during it’s action as a sunscreen as it is broken down.  Another to watch out for is Ethylhexyl Methoxycinnamate, which does the same.  It is particularly important when using chemical sunscreens to flood the skin with antioxidants pre and post sun exposure in order to treat this problem.

And finally…

People in the UK often forget that UV is still present even on a cloudy day.  The heat you feel from the sun is actually infra red rays, UV rays emit very little heat.  This means that if the UV index is over 3 then you should be wearing sunscreen even if it’s overcast.  This is particularly true if you are somewhere where there are reflective surfaces such as water, sand or snow.  Altitude also affects how strong the sun’s rays are, so the index goes up proportionately – if you are on the ski slopes then sunscreen should be applied as a matter of course.

For those of you who feel that life is not worth living if you can’t enjoy a sunny holiday, don’t think that this all means the sun is the devil – just please enjoy it safely!

References:

Cosmetic Chemistry by Florence Barrett Hill

Cosmetic Dermatology by Leslie Bauman, MD

sunsmart.com.au