We all know that prolonged exposure to the sun without protection is dangerous for the skin. But do you know exactly why light rays are harmful to our skin?
The effects of the sun's rays on the skin
Light is made up of fine particles, photons, which group together in wavelength according to their energy level, which forms the spectrum of light. On either side of this spectrum we find wavelengths not perceived by the eye: Ultraviolet and Infrared.The most energetic wavelengths, and therefore the most dangerous for our skin, are ultraviolet. The epidermis helps block certain ultraviolet rays but allows UVA and UVB rays to pass through, having a higher wavelength which can therefore penetrate further into the skin. It is UVA which will penetrate deep into the dermis, thus causing serious cellular damage and sometimes leading to a modification of the structure of the DNA, which can lead to sunburn and sometimes more seriously to cancers of the skin.At low doses UV causes little damage,theskin will then try to repair this damage by producing melanin, this is how we take on color and tan. Tanningis in fact a defense mechanism for our skin when it is exposed to UV rays.At high doses, however, the skin is no longer capable of repairing all the damage and developswhat we call a sunburn.When the skin is no longer able to repair cellular damage and we continue to expose ourselves without protection, the production of collagen and elastin, the proteins responsible for the elasticity and firmness of the skin, will be impaired. This phenomenon willultimately lead to skin aging. As a result, wrinkles will appear more quickly, the skin will sag and hyperpigmentation spots may appear.However, when cells fail to repair themselves, DNA is affected and the risk of cancer increases. This is why it is essential to protect yourself during each exposure.
Types of cancer
There are two types of cancer: carcinoma and melanoma.Carcinoma is the most common type of cancer, which often occurs after the age of 50, and which is mainly due to excessive and repeated exposure to the sun. Even if it is curable very well, there is however another variety of carcinoma, squamous cell carcinomas, which, when not treated in time, can leave metastases, in other words cancer cells which develop elsewhere than on the main source of cancer.Melanoma is a much rarer cancer but is very dangerous, since it has the capacity to produce metastases very quickly. It is therefore important to take care of it as quickly as possible. Melanoma can manifest itself by the appearance of pigmented spots on the skin or by the modification of an existing mole.
How to expose yourself safely?
To enjoy the sun safely, it is recommended to use sun protection adapted to your phototype. For example, if your phototype is low, that is to say your skin is white, your eyes and hair are light and you tan very little or not at all, you will need very high sun protection.But how do SPFs work?SPF,sun protector factor, is an index indicating the product's ability to attenuate UV rays. The number that we find next to the SPF corresponds to a multiplying factor of the amount of radiation that we can receive before getting a sunburn. For example, when we apply SPF 50, we can receive up to 50 times the UV dose before the sunburn appears. In other words, if it takes 1 minute for skin to get sunburned, with SPF 50, it will take 50 minutes for skin.This is why it is important to renew your sun protection at least every 2 hours, and especially after swimming. Sun protection should always be applied to very dry skin.All sun protection products with SPF are equivalent. Whether it is a cream, a spray, an oil or a balm. However, it is necessary to ensure that the UVA and UVB logo is indicated on the protection packaging in order to guarantee optimal protection. There are also two types of UV filters: mineral or chemical filters. Mineral filters often come from “crushed” rock, so they reflect UV rays, which is effective against UVB rays, which cause sunburn. Chemical filters absorb UV energy and have a broader spectrum, including UVA, which is responsible for premature aging, but also skin cancer. This is why it is recommended to use sun protection that has both types of filters to ensure you tan safely.It is also important to take care of your skin after sun exposure , in order to rehydrate and regenerate it, and thus repair the damage caused by UV rays.