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How sunscreen works

It comes as no surprise that sunscreen is one of the most important products to use on a daily basis for protection from the harsh and damaging ultraviolet (UV) ray of the sun; but how exactly does it work?

Sunscreen combines organic and inorganic chemicals to filter the light from the sun so that less of it reaches the deep layers of skin. Inorganic ingredients such as Zinc oxide or titanium oxide are considered reflective particles and work to scatter the UV radiation. Over the years they have made these particles smaller resulting in a less visible or whited out appearance. The organic molecules in sunscreen such as octyl-methoxycinnamate (OMC) or oxybenzone, work to absorb UV radiation and release it as heat.

Ultraviolet Radiation breaks down into 3 types:
UV-A – Not absorbed or block from ozone, it penetrates deepest into the skin and can lead to skin cancer and pre-mature aging.
UV-B – Partially blocked by the ozone layer, it is responsible for tanning and burning the surface of the skin.
UV-C – Completely absorbed by the earth’s atmosphere.

It is important to understand what SPF means and how to choose the best one for our skin type. The sun protection factor (SPF) measures how effectively the sunscreen formula limits the skins exposure to UV-B rays that cause burning. SPF is a number that you can use to determine how long you can stay in the sun before getting a sunburn and the higher the SPF, the more protection the sunscreen will provide again UV-B rays. Skin has a natural SPF, partially determined by the amount of melanin or how darkly pigmented your skin is. Take the number of minutes your skin can be exposed to sun without burning and multiply that number by the SPF on your sunscreen. The answer will give you the amount of minutes your skin can be exposed to the sun without burning when using this sunscreen. For example, if you can be exposed to the sun for 10 minutes without burning and you use a sunscreen with an SPF of 10, this would allow you to resist the burn for 10x longer or 100 minutes.

It is important to note that SPF only applies to UV-B protection so look for a product that indicates a broad spectrum of protection to work against UV-A rays as well. The regular use of sunscreen is one the best defenses you can use when it comes to protecting your skin.

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