Wednesday, May 3, 2017

What is sunscreen?

Sunscreen is a topical cream that contains ingredients that either absorb or reflect UV light coming from the sun. Octyl methoxycinnamate, for instance, is a chemical contained in some sunscreens that attracts or absorbs UV rays. Zinc oxide and titanium dioxide are found in many creams and reflect sunlight away from the skin.

Either way, sunscreens can be effective in helping to keep your skin from burning. If you are in the sun for any length of time, however, the effectiveness of a sun product (even if it has a high SPF) will be diminished. Why? Creams are no match for the power of the sun. Remember, SPF refers to burn time, not freedom from all sun damage.

Sunblock, by the way, is essentially the same thing as sunscreen, but it sounds like it totally blocks out the sun, doesn’t it? It doesn’t! It’s just another name for the same thing. Sunscreens and sunblocks are both helping to protect your skin when out in the sun, but both are only filtering UV rays. Both are keeping your skin from burning. So although a cream says it’s a sunblock, nothing totally blocks the sun except being inside.

I have used this example before, but I want to include it again for emphasis. If given a choice between wearing sunscreen on my face without a hat or a hat with no sunscreen, I would always choose wearing a hat with no sunscreen. UV rays can penetrate through glass, clouds, and water. Why wouldn’t they be able to cut right through a thin layer of cream on the skin? Obviously the optimum defense would be to wear both a hat and sunscreen, but I think you get the picture.

For more information, see:
Optimally, wear both sunscreen and a hat