The 5 most important things to know about sunscreen

I read somewhere that chemical sunblockers i.e. with zinc provide protection immediately. Is this true? Until I've been waiting 10-20 minutes before going out after applying sunblock. It would be very nice to just rub it on and leave the house.

There has been a ton of controversy about sunscreens lately, with studies on various sunscreens, and science and pseudoscience being quoted.

Recent media headlines proclaimed something like this: “Sunscreen chemicals found in the found in the blood after 3 days of use. ”  Then….when I read the study, they had 12 volunteers slather the sunscreen over 75% of their body four times a day for three days.   Who actually does that?  No one!

The 5 most important things to know about sunscreen:

  1. Think zinc.  It’s the only sunscreen ingredient that is natural to our bodies and blocks BOTH UVA and UVB rays almost completely.
  2. You want high percentages of zinc, or zinc plus titanium.  Depending on how much you’re outside, find sunscreens between 9-22% with the two combined.  For example, when you look at the “actives” total the percents of zinc and titanium and that should equal between 9 to 22 percent.
  3. To find the “actives” turn the tube over, and they are in a separate section from the rest of the ingredients.
  4. Protective clothing and hats ARE a sunscreen.
  5. Start your day by applying sunscreen first thing.  Then reapply as needed calibrated to your climate, outdoor time, activity and sweating.

Even better, the mineral sunscreens (zinc & titanium), don’t harm the environment and are safe for coral reefs.

Some great zinc sunscreens to try:

  • Image Prevention + Daily Moisturizer – untinted – for dry to normal skin (zinc 18%) SPF 30 (remember ….you don’t care about the SPF as long as it’s 30 or above.
  • EltaMD Clear SPF 46 (zinc 9%) – good for acne and oily skin
  • Dermaquest SheerZinc SPF 30 – tinted (zinc 18%) normal to dry skin.  Tint isn’t too intense.
  • Colorescience Powder SPF 50 Clear (zinc + titanium) greater than 40%  – great as a second layer when sweating, swimming, hiking, reapplying. Is light and small.
  • Trader Joes makes a 22% stick sunscreen which is small, and also nice for small areas like the nose & cheekbones.  Will clog pores!!
Hope this helps,
Dr. Brandith Irwin
Founder, SkinTour
Director, Madison Skin & Laser Center
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Dr. Brandith Irwin, MD

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Hi, I’m Dr. Irwin. I believe that consumers deserve a medically trained and unbiased skin care advocate.

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