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Sunscreens Questions

By February 9, 2023No Comments

Please explain the differences between mineral and chemical sunscreens?

Chemical-based sunscreens use chemicals to guard against the sun, while physical sunscreens use minerals, mainly composed of titanium and zinc oxide. This means that chemical-based sunscreens actually absorb the sun’s rays with chemicals like oxybenzone. A chemical reaction turns the harmful rays into heat, which is then dissipated from skin into the air. Natural, or mineral-based, sunscreens instead reflect the sun’s rays, like a mirror on the skin.

Does one work better than the other?

Both sunscreens work well. Some people prefer mineral sunscreen especially if they have sensitive skin or they are using it for young children. Chemical sunscreens also run the risk of an allergic reaction versus the mineral sunscreens.

What does SPF level really mean as far as the difference between 15 or 30 or 50?

SPF (sun protection factor) is the amount of increased protection a sunscreen provides. If you are like most people, you will begin burning after 15 minutes without protection. An SPF helps protect against sunburn but does not “stop” the tanning process completely.

Determine your protected sunning time by multiplying the SPF number by the amount of time it normally takes you to show signs of burning if unprotected.

For example: SPF 8: 8 x 15 = 2 hours of increased protection.
SPF 15: 15 x 15 = 3 3/4 hours protection.
If you burn in 5 minutes (usually very sensitive skin) with an SPF15: 15 x 5 = l h 15 increased protection.

The Skin Cancer Foundation recommends SPF’s of at least 15, which block 93 percent of UVB. While SPF’s higher than 30 block only 4 percent more UVB, they may be advisable for sun-sensitive individuals, skin cancer patients, and people at high risk of developing skin cancer. They also allow some margin for error if too little sunscreen is applied.

Are there ingredients to avoid?

Most importantly, oxybenzone absorbs UV light and protects your skin from UV damage, which makes it a good sunscreen. The drawbacks of the UV-absorbing organic compounds include a higher rate of allergic reactions in users.

How much and how often should I apply?

In general you should apply about a shot glass worth or 1 ounce of sunscreen for the body. For the face about 1⁄4 of that or 2 finger lengths worth. I suggest reapply every 2 hours if possible especially if you are in the sun.

Are SPF sprays as effective?

Yes they can be just as effective as a lotion but you need to make sure you spray adequately to cover the entire area.

Do you have a favorite?

My favorite sunscreens include Elta MD, isdin eryfotona actinica and Supergoop

Is there anything that you wish your patients knew about sunscreen or caring for their skin in regards to the sun?

I believe that no matter what age or ethnicity, sunscreen is very important. We know that sunscreen does protect you from the sun and helps prevent sun damage as well as skin cancer. Many patients state they are never in the sun. I tell them even if it’s 5 minutes in the car or walking around, that’s still being in the sun. Those 5 minutes add up to cumulative sun exposure.

Since so many of us are working in front of a computer daily, does blue light from our computer cause skin damage?

Studies are showing that blue light does penetrate the skin deeper than UV light and can cause sun damage as well as pigmentary skin conditions such as melasma.

If so, can sunscreen provide any protection?

Absolutely, I suggest physical sunscreen to actually block the blue rays.