We all know what strong UV rays can do to our skin if not well-protected.
Since sun exposure "ages" the skin, more and more foundations, powders and even lipsticks contain sunscreens.
But even when it says SPF 15 on the label, it may not be enough.
For the most part, dermatologists say sunscreens in makeup are great for incidental exposure to the sun (if you are walking from your car to your door for example).
But it's better to use a sunscreen all over your face under your makeup if you expect to be in the sun for longer than 10 or 15 minutes.