What ingredients should I look for in a moisturizer for dry skin?

The most effective moisturizers for dry skin contain a combination of humectants, emollients, and occlusives. Hyaluronic acid and glycerin are humectants that pull water into the skin. Ceramides and squalane are emollients that repair the skin barrier. Shea butter and petrolatum are occlusives that lock moisture in. A product with ingredients from all three categories will hydrate better than one relying on a single mechanism.