i do the same thing with make up.
if its day time i use sunscreen and then conceal the blemishes.or after 4-5pm i simply conceal few spots and thats it.
i too use a sunscreen that has zno but just 2%.its got a chemical block as well for complete protection from uva and uvb.
are u sure wheat effects u?
I'm not 100% positive that I'm sensitive to wheat, but I certainly noticed a big difference when I basically gave up bread. But it might have been something else: the yeast, for example, or some kind of preservative or something that's used in pre-packaged breads. I was tested for celiac disease and it was negative, but after some experimentation I've concluded that I certainly don't need wheat/bread/pasta in my life to function, and that if anything, wheat-based products seem not to agree with me very well. So at least for now, I avoid them.
I think that part of it at this point is psychological, too. If I'm convinced that avoiding wheat is healthy for me, then simply thinking that might make me feel ill after eating wheat. I may introduce it at some point in the future, but for right now, I have no reason to. I would never have guessed this, but after a year + of virtually no wheat, I don't actually miss it. The thought of sandwiches, bread bowls, and pasta just doesn't do it for me. I used to think "people like that" were lunatics! And now I'm one of them. (Sigh.)