When is it best to use Vitamin C serum?

Hi Dr. Irwin, I am wondering about using a Vitamin C serum in the morning under my sunscreen. I have read on several places online (and had one aesthetician tell me) that Vitamin C breaks down in the sunlight. She said that your skin won't benefit from it if you wear it during the day under your sunscreen. I'm wondering if I should only use it at night? Thanks so much. I read your book and changed my skincare routine based on it, and I'm lovining your recommendations and the results! Wendy

Well, she’s sort of half right on this but here’s why you should still use in the morning.   When you put in on it binds to your skin cells.  When the UV rays hit the cells and create free radicals, the Vitamin C protects the DNA of your skin cells from damage by scavenging those radicals.  So…..  in a sense it is breaking down but you want it to!!!!  That’s the way it protects the DNA of your skin cells.   I recommend using it under your sunscreen and using your Vit A cousin creams at night.    Dr. I

Dr. Brandith Irwin, MD

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