Why does our skin peel when we get sunburn?
Today is Red Nose Day. I for one know that one of the reasons my nose becomes red without the addition of a cute charity nose (this year mine is called Snuffles) is because of sunburn. But just why does our skin peel if we stay in the sun for too long? This post will clarify that.
Sunburn is actually caused by UV radiation which comes from the sun. This is why people can get sunburn on cloudy days when they are at high altitude. It is no secret that radiation can lead to cancer – hence why excessive exposure to UV rays can lead to skin cancer.
The radiation causes mutations in DNA within the skin cells. This is obviously potentially dangerous for the body, but luckily the body has self defence mechanisms which it can put into place to protect itself. The cells undergo ‘cell suicide’ – because they cannot repair all of the mutations, they sacrifice themselves. This allows healthier cells which have not been affected by the UV to replace them. This is what the peeling skin is when you get sunburn – the cells which have sacrificed themselves in the outer layer of your skin all falling off in clusters.
The redness and inflammation which we all associate with sunburn is also a protective mechanism by the body. The inflammation is as a result of chemicals being released by cells in the body. These reduce the body’s sensitivity to heat – meaning that you will feel pain at lower temperatures than normal. This may feel like the body is damning you to more pain as punishment for staying in the sun too long. However, it is actually the body protecting you. If you feel pain at lower temperatures, you are more likely to get away from the source of the pain. This therefore means you are much less likely to remain in temperatures where you can harm yourself further.
Risk of sunburn is affected by age and skin tone. This is commonly known – we are hugely concerned with ensuring young children and the elderly have high strength sunscreen on, but do we know why? We also know that those with darker skin are much less likely to burn, same with those who tan easily. However, the lucky ducks like myself who are exceptionally pale burn very easily if they are not too careful when out on a hot and sunny day. Why is this?
Melanin is the pigment which we all contain to varying degrees. It protects the DNA from radiation by absorbing the UV. Melanin levels indicate tolerance to the intense sunlight. Hence why there is so much variation in skin tone – those who descend from countries where there are long days of intense sunlight will have much darker skin in comparison to those who descend from countries where there are shorter days with less sunlight.
So there you have it. Sunburn isn’t convenient, but it is preferable to skin cancer. Just don’t go on sunbeds which increase your risk massively due to such intense radiation in such a short space of time. Also, if you’ve got pale skin: slapping on fake tan and trying to convince me you’ve been to Mauritius won’t work – I know you’re unlikely to tan (and nobody tans tangerine orange anyway).
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