It is so much better to listen to what people say and do. It means that the person thinks that it is easy to either predict or see by your facial or body expressions what you are thinking or what you will do next. Think of poker players and how they hide their reactions to their cards.
This doesn't mean you can take vitamins or apply topical vitamin C and then bake safely in the sun, but you can help keep your skin healthy and supple by making sure you get enough of this antioxidant vitamin [source: Bouchez].
Vitamin C is a chemical called ascorbic acid that is naturally occurring in skin. It is known to play a role in collagen production. In addition, when topically applied it is thought to help heal acne, increase the barrier function of skin to decrease moisture loss, protect from UV radiation, and prevent age spots.