Many of my clients ask me about what SPF grade products one should use. My answer is quite simple: you need SPF, period. It does not really matter, Sun Protection Factor, is needed. Is there a difference between SPF 15, SPF 45 and SPF 100, absolutely? But, not all products are the same.
The SPF grading in the USA goes through quite rigorous process, in addition, more SPF grading means more stickiness…you will have to smear a white layer in order to get a higher SPF benefit.
Also, your SPF requirements depend on your skin type. I have a friend of mine from Charleston, WV, regardless of the SPF he uses, in 5 minutes his face will look like a red tomato. I suggest you start with SPF 15 and see the results for yourself and go upwards if you want more protection.