by Dr Tiina Meder
These days no one would deny that we need protection from the sun. But really, why is that? Ultraviolet rays exuded by the star we call Sun have a variety of harmful effects. Excessive exposure to UV leads to pigmentation, the disturbances of skin pigment’s synthesis and distribution, thickening of the keratinous layer (rough skin), vascular damage (couperosis, persistent skin redness etc), excessive or insufficient sebum production (dry or oily skin), damaged barrier function (increased sensitivity, proneness to inflammation), accelerated ageing (wrinkles, decrease in skin’s elasticity and firmness).
The scariest thing is, of course, that ultraviolet can penetrate into deep skin layers and damage cell structures there, altering skin cells and leading to the development of various tumours, including the dangerous melanoma kind.
However, these days cautiousness seems to have progressed into something truly radical: there is no safe tan. I’d venture to say, that most of you know or have heard that skin needs anti-sun protection at all times, regardless of your location, weather forecast and your plans for the weekend. I get where it comes from. When you need to warn millions of people about the dangers of excessive sunbathing, the chances of them hearing you increase when you issue a blanket statement: always use sunscreen, rather than go into tedious details of when and where one actually needs protection. And if someone overdoes it and avoids the sun when it’s not necessary, it would still work out.
Right? Well, I find this approach stifling and counterproductive, to be honest. I don’t think we need this extra fear in our lives prompting more and more people every year to experience heliophobia and try to avoid the sun altogether, which is hardly healthy.
The key factor is that the sun rays don’t fall on the land evenly. On the same day people in Shanghai may need protection, while people in Sweden do not. Most weather-predicting websites these days display Index of Ultraviolet or IUV expressing the intensity of ultraviolet radiation in the atmosphere and the potential danger for the skin. The higher the number, the more ultraviolet is out there.
When the index is 0-2 (and in the absence of extra risk factors) no one needs sunscreen, not even people with really light and sensitive skin.
3–7 means: wear long sleeves, sun glasses and hats, apply sunscreen, try to stay out of the sun between 12.00 and 14.00.
7 and higher is a reason to avoid the open sun from 11.00 till 16.00, stay in the shade, cover yourself with clothes, sun hats, sun glasses and apply maximum protection sunscreens frequently.
To give you an example, IUV 0–2 is most days in London from November to March; IUV >8 is Darwin, Australia practically every day. Obviously, people living in London and Darwin would need different strategies of skin protection.
Other factors at play are: local altitude, the presence of reflective surfaces, air pollution. The higher you climb, the more intensive UV effect you experience. Amsterdam is 2 m below the sea level, while Denver is up to 1.6 m above — clearly, a Denver resident will need sun protection more often than a person living in Amsterdam. The UV action is intensified when the sun rays are reflected by a shiny surface, so next to open water, sandy beach, snow slope, etc UV damage of the skin becomes more probable. Air pollution is a bit tricky: on one hand, dusty air creates sort of a screen against UV radiation, on the other, air pollutants themselves have a serious harmful potential and increase the skin’s sensitivity to ultraviolet. So, in the highly polluted areas the risk of UV exposure increases even when Index of ultraviolet is as low as 2–3 and one can end up having pigmentation and other unpleasant consequences of sun damage without even knowing how it happened. If you live in a big city, check your Air Quality Index or AQI to access the danger of UV.
Now we’ve come to the main point: the skin’s sensitivity to UV. When we’re discussing sun protection, we would normally be talking about healthy skin. When sunscreens are tested, the trials always exclude volunteers with any kind of skin damage and those taking medicine which increases the skin’s sensitivity to UV. The bad news is — it’s a lot of medicine. A wide variety of pharmacological bestsellers makes the skin more vulnerable: non-steroid anti-inflammatory drugs, such as ibuprofen, oral contraceptives, antidepressants, many kinds of antibiotics, and we can keep going.
AHA-acids and retinol are known culprits, but also some derivatives of hydroquinone and arbutin, which is why these should be avoided during sunny seasons (have you ever been warned about that?). The nastiest surprise, however, is that the champion in causing increased sensitivity and even phototoxic reactions is… certain type of sun filters found in some sunscreens.
Some of them (not all, thankfully!) go through a certain transformation as they absorb the energy of UV rays and turn into harmful substances.
If you only spend a little time in the open sun, you should be ok, but when you’re planning a 1.5–2–hour outing, pick your protection carefully. Cosmetic manufacturers try to make their sunscreen formulations as stable as possible, but they do face certain limitations: regional legislation (for example, in the US some sun filters are banned, while in Europe they’re in use), price, people’s tastes, etc. Mineral filters, such as titanium dioxide or zinc oxide, are always stable, which is why mineral-based sunscreens are recommended for children and people with sensitive skin. Among sunscreens’ ingredients the following can potentially increase UV sensitivity and even lead to photodermatitis:
Para-aminobenzoic acid (PABA)
Isoamyl-p-n,n-dimethylaminobenzoate (Padimate O, Escalol 507, OD-PABA)
Glyceryl-p-aminobenzone & other ethers PABA
Oxybenzone & other benzophenones
Another factor to consider is general skin health, and don’t mean dermatological disease necessarily: excessive dryness, oiliness or sensitivity, the aftereffects of cosmetic treatments can increase UV damage.
Finally, the way you apply your sunscreen matters! Research on how customers tend to apply sun creams (people study all kinds of things, don’t they?) demonstrates that generosity is very uncommon. Alas, data shows that users apply less than half of recommended amount of sunscreen. Numbers don’t lie. (Curiously, cream from a jar with wide opening tends to be applied more generously that the same stuff from a pump or spray bottle.) SPF is calculated in lab conditions, when the cream is slapped on liberally, and if you don’t apply enough, you don’t get the claimed level of protection.
Wait for it, and you’ll know right away why no one does it. To protect your face and neck, you need at least 5–7 ml of sun cream, and for your body (of average size) you’ll need another 30 ml, some recommend up to 45 ml. Now, imagine you bought a pricey 250 ml jar of sun cream. How much will it last you? You got it, 7 applications max. If you’re on a beach, you should reapply sun cream every 2 hours, more often if you dunk in the water or turn around on your deck bed. Water rinses off your sun cream, and towels wipe it off of your skin, eliminating your protection.
So, what’s the conclusion?
The necessity and amount of sun protection should be determined “in the here and now” according to the intensity of UV radiation in this particular area, sea level and time of year. The higher above the sea, the more reflective surfaces around you, the more air pollution, the stronger sun protection you use. However, if you live in a nice clean valley somewhere in the north, away from sea and mountains, chances are, you’ll only need sunscreen for a few weeks in the high summer.
Your skin’s characteristics are a factor, along with the quantity and quality of your sun cream. Check if your regular medication or nutrition supplement has a photosensitising effect and adjust your protection if needed. Remember that healthy skin is easier to protect and take good care of yourself with adequate skincare, correction of excessive dryness, oiliness or sensitivity and remaining sensible about aesthetic correction. Laser resurfacing and injections are better left until after your beach vacation or skiing holiday (much later).
Choose your sun protection wisely. Mineral-based sunscreens are the safest option, but yeah everyone will know you’re wearing a sun cream (like a sensible person). Personally, when it comes to kids, or when you’re on a beach or a ski slope, I don’t see anything awful in that. However, if your city life requires looking a bit smarter than that, choose a less noticeable protection from a wide range available, including makeup foundations or BB creams with SPF. In most cases, SPF 30–35 is enough in the city, unless you spend several hours in the sun each day. For your body, clothes are the best protection: the thicker and darker the cloth, the better protection it provides. It’s pretty straightforward: silk and thick cotton are good choices, sheer mesh — not so much.
When you choose your sun cream, consider the ease of frequent application and the affordability of buying lots of it. There are many inexpensive quality sun creams out there, and it is infinitely better to buy a cheaper solution twice a week and use lots of it, then bring a small bottle of an expensive one, even if this one is state-of-the-art sunproof protection. Be realistic: if your heart bleeds with every drop of sun cream you apply, or if the application is for some reason not easy, you won’t use it as much as you really need and end up burning.
Finally, even if you are clad head to toe in brightly coloured silk and what little skin you have exposed is perfectly healthy and lathered in the best sun cream, it still doesn’t mean that spending all day in the open sun is a clever idea. When the sun is scorching hot and high up in the sky, shade is the place to be.
Dark skin naturally produces more of a chemical called melanin which gives skin color and helps absorb the sun’s damaging UV rays. The darker the skin, the more melanin it contains. While melanin can be helpful in screening out some of the sun’s harmful UV rays, it only offers a small percentage of protection from the sun. It’s very important to take additional steps to protect the skin. Choose a sunscreen that offers full protection. Look closely at the labels before you buy, and opt for a product that promises:
Broad-spectrum protection. Sunscreens like this protect your skin from UVA and UVB rays from the sun. Both can cause cancerous changes in the skin.
High sunburn protection. Products that boast an SPF of 30 or higher offer complete protection from sunburn.
Water resistance. Products with this label will stay on for 40 minutes after you’ve taken a dip in a body of water.
Follow the dermatologist's advice and enjoy the sun safely!