I use Elemis and Dermalogica which have SPF in their day creams – should I be using a standalone sunscreen as well? Thanks

To be honest, I’d prefer that you used a standalone sunscreen on top, unless you’re using a really good thick layer of that moisturiser all over your face and neck. When companies test the SPF of their products, they use a standard thickness of 2mg per square centimetre of skin, which comes out as quite a lot. Most of us don’t use enough product to get that coverage, whether it’s with a moisturiser-with-SPF or a sunscreen, which is why I’d always opt for doubling up.