SPF

We are constantly told that exposure to the sun can cause skin cancer and that we should use creams to avoid it. I have found that this vital advice is not easy to follow as the preparations are not always clear in their instructions. For example, one facial brand, even recommended by dermatologists, says it is for 'daily' usage but does not say if that means that it lasts all day (unlikely) or that it can be applied each morning. Also I have wondered if, having rubbed in one colourless version with a SPF of 15 and then another as make-up, that adds up to 30. Surely manufacturers should be forced to be transparent over this.