Why Do We Get Tanned From Laying In The Sun?

Your eyes are closed, your hair is in a bun, and you hear the waves rattle the tiny shells in the golden sand. Some salt is drying on your body while you feel the sun burning on your skin. You may feel some parts of your body getting a little sunburned, but other than that, everything feels perfect. Just you, relaxing and getting tanned on the beach on a sunny day. Nothing to worry about, right? However, did you ever ask yourself why we get tanned while lying in the sun? Stay where you are; there is no need to move; just keep laying on your beach towel, and you will find out the answer by reading this article.

First, it is important to learn a little more about ultraviolet radiation and the structure of your skin. Sunlight consists of different types of radiation, but ultraviolet radiation (UV light) is the kind that causes your skin to get browner or redder. There are three types of UV light, classified by wavelength: UV-A, UV-B, and UV-C. The ultraviolet radiation in the atmosphere is 90 to 95 percent UV A and 5 to 10 percent UV B. UV-C is completely blocked by the ozone layer and is therefore not in the atmosphere.

In the third layer (stratum basale) of the epidermis, there are melanocytes. Melanocytes are cells that are able to produce melanin in a process called melanogenesis. Melanin is a natural pigment and protects the body by absorbing ultraviolet radiation. There are two different kinds of melanin, namely pheomelanin (red) and eumelanin (dark). There are also two different kinds of tanning processes. UV A is important in one process, while UV B is important in the other.

UVA-process

The UVA process is also known as the short-term tan process. Oxidative stress is the result of UVA radiation hitting your skin. Already existing melanin gets oxidized during oxidative stress, and that leads to a rapid darkening of the melanin. The redistribution of the melanin in your skin is another result of UVA radiation hitting your skin. That means the melanocytes in your skin are releasing melanin that was already stored. Those two effects of UVA radiation don’t lead to significantly increased production of melanin or protection against sunburn. The effects of the UVA tanning process are visible very quickly, but they also disappear very quickly. That is why it is also known as the short-term tanning process.

UVB-process

In contrast to no significantly increase in the production of melanin during the UVA-process, is there a significantly increase in the production of melanin during the UVB-process. That is the body’s reaction to the direct DNA photodamage from UV radiation. This increase in the production of melanin is called melanogenesis and causes your skin to get tanned. This type of tan takes longer to appear and fade than tans produced by the oxidation of pre-existing melanin during the UVA-process. Additionally, the tan created by the UVB-process is actually protective against UV skin damage and sunburn.

That is the explanation behind the phenomenon of getting tanned in the sun. Since you were reading this article while lying at the beach in the sun, your skin probably got more tanned. Now that you know how the different tanning processes work, you also know what the sun is capable of and that it is really important that you protect your skin against it.

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