Do I need to reapply my sunscreen at the end of the day at my office?

Love your site, I’ve learned so much – Thanks!! I have a question on sunscreen. My morning routine includes using a separate sunscreen, currently the Skinceuticals Sheer Physical UV Defense 50. Throughout the day I blot my face w/ tissue to control oil. When I leave work around 5, is my skin still protected or does the sunscreen lose potency by sitting in an office all day? Thanks!

You’re welcome!!  Sunscreens do degrade on the skin over time slowly with exposure to light, blotting or wiping the skin, exposure to our natural skin oils, etc.  I’ve never seen a study on how fast they degrade in an office environment.  The real question is what are you doing when you leave the office?  If you are in the car for awhile, walking outside, going for a run, etc., I would recommend reapplying the sunscreen before you leave the office.  Dr. I

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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