The heat and recent spate of beautiful sun-drenched summer days has enticed most of us in the southern hemisphere out to the beaches, parks and swimming pools in search of a wet escape to cool off. It is natural to want to make the most of the sunny summer weather, soak up as much vitamin d as a body can take and tan ourselves back to health.
But if you are anything like me it is a fine line to tread between tan and sunburn, and despite best efforts often that line is crossed much to our pain. Too long between sunscreen applications, too much time in the pool, couldn’t find a hat, the excuses are many and varied, the result mostly the same. So I thought I would look into exactly what sunburn is, to try and explain/learn what it is that is happening to us when we stay too long under ‘big yella’; because forewarned is forearmed, or something like that.
So here we go;
According to Jeffrey M. Sobell, an assistant professor of dermatology and director of photo-medicine at Tufts University School of Medicine; “Sunburn is when ‘The energy from ultraviolet radiation damages molecules in the skin, most importantly DNA’. A consequence of this is the synthesis of different proteins and enzymes. The effects of these proteins, notably prostaglandins and cytokines, leads to dilation of the cutaneous blood vessels and recruitment of inflammatory cells, in turn, producing a sunburn’s characteristic redness, swelling and pain”.
So Sunburn occurs when our exposure to UVA & UVB is at a rate in excess of what our natural defence mechanism can withstand in a given time period. The body can only do so much, overload it and we cannot handle all the UVA & UVB, proteins get synthesised that inflame the skin and we get burned. Easy.
But what is UV exactly?
Ultraviolet radiation comes in three wavelengths; UVA which is the main tanning ray. UVB, which is the chief cause of skin reddening and sunburn on the skin’s more superficial epidermal layers. And UVC, which is mostly dispersed before the ozone layer and does not reach us. As has been said already prolonged exposure to ultraviolet radiation creates a toxic reaction in our skin cells producing redness and that characteristic tight skin we associate with sunburn. All of this from the suns rays.
To be clear, the damage we get from a sunburn is different from that we get when we put our hand on a hot coal or under boiling water, those are thermal burns, the result of direct heat on our skin.
As you may have picked up from Assistant Professor Sobell in his paragraph above, the process of becoming sunburned is in fact a very complex one and although science can tell us a lot about what creates sunburn and how it occurs scientists admit that the exact reaction that happens in the cell is still somewhat of a mystery and a matter for much debate.
What isn’t in doubt is that ultraviolet radiation can damage molecules in our skin and most importantly DNA. In doing so our blood vessels are caused to dilate and inflame causing the redness, heat and swelling. This can take many hours to occur which is why often it is not until well after the event before we realise we have indeed been burned.
Yet it’s not all bad news, we do have weapons in the fight against UV. It is in fact UV that stimulates the production of the pigment Melanin, which absorbs ultraviolet light breaking it down as heat. Melanin has been described as the body’s natural sunscreen and it is Melanin that gives us a tan. This process helps prevent much of the damage responsible for the formation of malignant melanoma and other skin cancers.
The make up of skin itself also serves to provide protection in certain areas like palms of the hands or soles of the feet where the skin is thickest. Likewise darker skin types do not burn as much because of additional melanin throughout the epidermis and body hair can act as a physical barrier and prevent sun damage as well.
Even once damage has occurred our bodies do have the ability to repair damaged DNA, especially that caused through sun exposure. In fact the latest studies are showing that the inflammation after sunburn is actually a good thing and is our body trying to repair damage and prevent it turning to cancer.
But like anything our body’s repair and defence mechanism is imperfect and the more we stress the system the more likely some of the damage will escape repair and potentially become a bigger issue — Melanoma.
So in the end it seems like so many things, it comes down to a lot of common sense. Understanding the harmful effects of UVA & UVB, being sun aware and self-aware and taking the risk of prolonged exposure seriously — doing these things will most likely safe our lives. The process of sunburn is a complex one and not easy to explain or to fully understand even by brighter lights than myself, what is not hard to understand is that going out in the sun unprepared or in search of that perfect tan, for most of us is a nonsense of mammoth proportions and if we are not careful can become a fight that eventually we lose.
In penning this I’m not certain I have adequately explained sunburn on even the most superficial level, what I have done is convince myself that allowing myself even a little ‘burn’ is tantamount to playing with fire and no matter how tempting that little extra tan time is, I will be slipping, slopping and slapping a little more regularly for the rest of this long hot summer.
Below are links to the references for this article along with a few additional links that the eager reader might find interesting. Enjoy.