Do you apply sunscreen separately or do you rely on the SPF in your make up or moisturizer to protect you? The highest SPF I have ever seen in makeup is 50, but generally I only see 30. I have read that dermatologists recommend using at least SPF 30 for everyday use, but when you rely on your makeup or moisturizer you'd have to use so much to get the benefits that the SPF is almost cut in half. Personally I use a separate sunblock because I don't want to have sun damage but I know plenty of people who only use their makeup...if anything!
I have both at my disposal. I cycle a lot and the wind can tend to dry out my skin so a moisturizer can be helpful. The stuff I have has an SPF rating of 15 which is good enough during the spring and fall when I will be out for a few hours on the bike. Today, my short ride turned in to a longer one than planned and the hazy clouds evaporated to reveal sunshine. I keep an SPF 30 block in my pack for these occasions. I also have 30 for those days when I plan to be in the sun for a period of time. I think the dermatologists are a little overly paranoid and want us to have baby skin at 80 years of age. For me, the key is not to burn. Unfortunately most of the sun damage I have would have occurred in my youth and in the days when people went out with baby oil to enhance the sun's effect.
