Eli5: How does sunscreen work to protect your skin?


Eli5: How does sunscreen work to protect your skin?

In: Chemistry

It actually absorbs some of the UV rays and changes that energy to heat. So the more UV that changes to heat, the less that impacts your skin and causes a sunburn.

There are 2 types:
A. sunblock/physical sunscreen/mineral sunscreen(which reflects the UV rays from even hitting the skin) and

B. sunscreen/chemical sunscreen(which absorbs the UV rays and disperses the photons to make a safe amount of heat to just sit on the skin.

1. What is sunburn?
If you sit out in the sun too long without protection, the UV rays make their way under your epidermis, burning that layer(which is a 1st degree burn in most cases). I think of radiation as a bunch of little heat worms that can wiggle their way in anywhere, and liquids help amplify the rays, kind of like making it easier for the worms to wiggle in.

Chemical sunscreen: It’s like a radiation suit you can spray on! The layer absorbs a dangerous amount of the suns UV radiation by a chemical reaction, which turns the most of the UV rays into heat which will be rid of eventually, and it also does some reflecting on the rest of the radiation

Physical/mineral sunscreen: It’s like a less hot sweaty version of the other! This particular type of sunblock completely prevents the rays from going past the sunblock layer at all. But before you switch to sunblock, here are a few need to knows:

1. Sunblock is much thicker and not clear/most cannot be sprayed
2. Sunblock does NOT block the whole spectrum of UV radiation, while sunscreen does block it all.
3. Most contain titanium dioxide, which can be problematic for some.

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