Having had epilepsy for over 50 years, my skin has been affected by allergic reactions and more due to constant medications. I am also allergic to wheat, dairy, protein, spices, and seafood which cause havoc on the skin. Perfumes, colors, fragrances, and chemicals in washing powder, dishwashing liquids, etc. also cause problems.
I stopped wearing makeup several years ago due to reactions, and only use hypoallergenic soaps, creams, and shampoo/conditioner.
My skin has always been very dry and I have found the Simple range good for skin problems/sensitivity. I also use Vaseline Repair Cream after a shower which definitely has helped rejuvenate dry skin.