DAMAGES OF THE SUN: THE EFFECTS OF UV RADIATION ON SKIN

How the sun damages your skin?

By now you must have heard the importance of sun protection for your skin in the prevention of sun damages and skin cancers. Despite all the information available, many of us do not always make sun protection a priority. As someone accustomed to sunny weather, I do not burn easily and I'm not aware of the sun’s immediate effects. It is therefore not natural behaviour for me to be overly concerned about sun protection. I mean, can it really be that damaging?

Prevention is better than cure

The old adage prevention is better than cure remains true. When faced with skin problems like sun damage, we want an easy and fast solution. Maybe a procedure here, the latest and greatest innovation in skincare formulations or the newest technological advances in laser therapy, the strongest acid peels. Not that we should be wearing sunscreen. To have one magic pill or potion erase years of neglect is just more appealing. The fact remains that years of sun damage can easily be averted, provided we take small measures of prevention. However, we must first understand how it happens so we can identify how to prevent it.

The lowdown

Now that we are aware of sun damage, what are the effects of prolonged sun exposure and why does sun damage even happen? Oftentimes, we wait until we see visible signs of a problem be it an ailment to take action. It is however prudent to remember that, the little steps we take daily makes the greatest of impact; little drops of water makes an ocean. This applies to our skin and the prevention of sun damage. Why wait for visible signs of sun damage to surface before taking action? We should always endeavour to mitigate effects by adopting preventive measures. I understand that sometimes only evidence can make us act on something. Simply being told to do something without facts to back it up is not enough motivation to get moving. I mean, some of us hate being told what to do. Here's a breakdown of what UV radiation does to skin.

UV radiation

Ultraviolet (UV) is part of the electromagnetic spectrum of radiation that falls between visible light and X-rays. The sun emits this UV radiation but unlike light rays or infrared, it can't be seen or felt. UV radiation has been classed as a Group 1 carcinogen, simply put, it has strong cancer-causing potential.

There are different types of UV radiation: UVA, UVB and UVC. UV radiation is classified as a carcinogen due its tumour promoting and tumour initiating effect. UV radiation contributes to the depletion of stem cells, causes stem cell DNA damage and eventually leads to photoinduced ageing of skin. All these happen when we are exposed to the sun.

It is paramount we save the ozone layer as this will not only save the environment, but save our skin too!

The ozone layer acts as a protective barrier to absorb a lot of UV radiation from the sun. UVC is completely filtered out by the ozone layer but UVA and UVB are still able to reach the earth’s surface. The continuous depletion of the ozone layer, a direct result of certain compounds and pollutants being released into the atmosphere, poses a risk in aggravating the health effects caused by these harmful rays.

Here, I am going to focus on ultraviolet A and ultraviolet B as they relate to sun damage of the skin and aging.

The difference between UVA and UVB

The difference between UVA and UVB rays

What are UVA rays?

UVA rays account for most of the sunlight reaching the earth's surface and penetrate deeper than UVB. This means that they have the ability to penetrate into the deeper layers of the skin at the dermis. These rays are responsible for the adaptive melanisation (or tanning) of our skin. Melanocyte cells respond to UVA rays by triggering melanin to darken the skin in an attempt to protect it. Skin darkening from a tan is the skin’s response to DNA damage.

Silent killer

Physically, you do not feel the effects of the damage on your skin because unlike sunburn, solely tanning is not unpleasant or uncomfortable. It is important to note here, that just because our skin doesn't show the immediate adverse effects of sun damage does not mean it hasn't occurred or is not occurring. For those who thought that if we simply tan and are not prone to sunburn, we are at less risk than those who burn.

Continuous UVA exposure ages skin cells faster, damages DNA, causes the formation of wrinkles and is responsible for the majority of skin cancers. As long as the sun is out, UVA rays are present. They're strong and can penetrate glass, even when indoors, if you are in a building with windows, you are being exposed to UVA rays.

What are UVB rays?

UVB rays have a slightly higher energy as against UVA rays. They are especially pervasive at high altitudes and on reflective surfaces but do not penetrate glass significantly in the way UVA rays do. UVB is mainly responsible for the reddening of skin and erythema (sunburn) and plays a role in skin cancer. Its inflammatory properties kills keratinocytes which results in sunburn.

This type of UV radiation mostly affects the surface epidermal layers of the skin but also contribute to tanning and photo-ageing. It causes skin pigmentation by increasing melanin synthesis. The oxidative stress caused by UV exposure increases the production of reactive oxygen species, leading to the proliferation of epidermal keratinocytes. These accumulate and increase epidermal thickness so that the surface layer is dull, dense and crepey.

Burn

UVB is more effective in inducing immediate sunburn, but does trigger melanin synthesis and will ultimately lead to delayed tanning. The overproduction of melanin skin cells can form patches of darker skin. That is hyper pigmentation, dark spots and dullness. With age, comes a dense, dry and dull outer layer of the skin.

Vitamin D

UVB also plays a vital role in producing vitamin D, a steroid hormone that regulates over 1000 biochemical processes in the body. It is vital to keep vitamin D levels in check while also protecting yourself from the sun. The believe that tanning booths are a good source of vitamin D is erroneous since UVA rays are mainly the type used in tanning, and not UVB. Don't buy into any of that misleading information.

Protect your skin from the Sun

Some easy steps to follow and keep your skin protected from the sun:

Apply a broad-spectrum sunscreen to the exposed areas of your skin. Don't forget the hands and ears

Reapply sunscreen every 2hrs, after swimming or sweating as it can wash off

Shield your eyes with sunglasses

Stay under a shade during peak hours of sunlight

Wear hats to protect your scalp and face and umbrellas

Avoid skincare ingredients that increases photosensitivity

Do not allow your skin burn

Use a lip SPF

Avoid tanning booths and use self-tanners instead. Or go au naturale.

Ingredients that causes sun sensitivity

There are quite a number of skincare ingredients that increases the skin’s sensitivity to the sun. Such ingredients include various fragrant plant oils, glycolic or lactic acids and benzoyl peroxide. This means, if you have any of these ingredients in your skincare routine, there is an even greater reason to use a broad spectrum SPF daily.

Various ingredients also help to lessen the adverse effects of excess sun exposure, good examples are vitamin C and hyaluronic acid can help to strengthen the skin barrier.

What does SPF do?

The SPF rating on sunscreens refers to the protection from UVB rays. This essentially tells you how long you can stay under the sun before your skin starts to burn. For example, if your skin begins to burn after 15 minutes in the sun, applying an SPF 30 means it will take 30 times longer before you burn.

Due to the lack of liberal sunscreen application, it is advised to apply an SPF 30 or more so you can be assured of adequate sun protection. An SPF beyond 50 can be misleading. It might probably be more beneficial to frequently reapply an SPF 30, than to assume an SPF 100 will protect you effectively. Some countries ban a rating over SPF 50 due to the false sense of security it gives people.

In terms of percentage of UVB radiation that SPF will blocks out, SPF 15 sunscreens will filter about 93% of UVB rays, SPF 30 sunscreens filter out about 97%, SPF 50 sunscreens about 98%, and SPF 100 about 99%. As the SPF rating increases, the difference between consecutive ratings becomes smaller. Do note that no sunscreen will block out 100% of all UV rays.

What to look for in a sunscreen

Due to the fact SPF relates only to protection from UVB, go for a broad spectrum sunscreen. This will shield you from both the UVA and UVB rays and will protect you from the visible surface level effects of sun damage as well as the deeper level damage to the skin.

Stay vigilant

It might feel a little wasteful or redundant sometimes to slap on sunscreen just to pop outside for a couple of minutes, or during a cloudy day. It might take some practice to get used to daily usage of sunscreen. Remember that although you cannot feel or see the UV rays, they are present at all times – apart from nighttime when there is no sun. As long as you can see outside, sun damage is able to occur, and the damage is cumulative.

The best time to begin to take adequate protection of your skin and prevent further harm is now. Constant protection against UV exposure is simply ensuring that you are taking care of your health. The skin is the largest human organ; it’s a living organism. Take care of it and it will of course take care of you. There is such a thing as skin-vestment

Hope you found this helpful. Don't forget to leave us a comment and tell us your sunscreen experience.

Thank you for reading!