Has anyone found a way to prevent the above when wearing a mask. I have such a problem that i end up taking them off most of the time as i cant see where i am going or what i am lookng or in the supermarket!!! I even asked in the opticians for a trial spray of their product for this and then went off to shop hoping it would work and if it did i would have gone back and purchased a contatiner of it. But as soon as i left the shop they fogged up again.