We spend millions on supplements every year but when it comes to hair, skin and nails do they really work? Dr Hannah Sweilam finds out. Let’s talk about hair, skin and nail supplements. We’ve seen adverts that claim these supplements can promote healthy hair, glowing skin and strong nails, but is there scientific evidence to support these claims? Often these claims centre around the vitamin ‘biotin’ which is commonly included in these supplements and marketed as a go-to vitamin for beauty.  Biotin is a B vitamin- also known as vitamin B7- and in common with other B vitamins, it helps…