I'm not sensitive to the sun. I'm just a part of that set who's paranoid about skin cancer.
The 15 minutes/day would probably be fine, except it's said that at this time of year in places such as Canada the sun isn't strong enough. It isn't strong enough for more than half the year. Plus the 15 minutes thing only applies if you have your arms and legs uncovered. I'm not doing that when I can see my breath.
The other thing too is smog. I live in the "Big Smoke."