Why do I have to wear sunscreen under foundation?

Kbxl’s question…Hello Beauty Brains! I’ve seen it recommended to use sunscreen under foundation. What’s the point, wouldn’t foundation act inherently as a sunblock anyway? I’d like to know your opinion on this. Thank you!

The Beauty Brains’ response:

No, foundations by themselves are NOT adequate sunblocks.

Even though they contain ingredients that can cover your complexion, all foundations do not contain ingredients that absorb or block UV rays. And even though some foundations DO have an SPF rating, experts agree that this by itself is not enough protection. That’s because the SPF rating is usually quite low and because you don’t apply enough foundation to get adequate protection. Finally you may not apply foundation to all areas of your face, head, and neck that need to be protected. Suncreen works much better!