When we're young, the stratum corneum naturally replaces itself about once every two weeks [source: MySkinCareConnection]. As we age, this process slows down, and the dead skin cells that largely make up this top layer of our epidermis tend to stick around a bit longer. With dry skin, the problem is amplified further, as the dead skin cells continue to build up and can give your skin a flaky, ashen or even scaly appearance.
When you exfoliate, you're basically tearing off the stratum corneum. However, xerosis goes deeper than your skin's leading layer, and even if you use an exfoliant that provides skin moisturizing benefits, your dry skin problem won't be solved instantly.
Exfoliation is, however, a great place to start. By stripping away the stratum corneum, you'll improve your skin's texture and allow moisturizers direct access to living skin. The moisturizing elements contained in the exfoliant will have a much more dramatic effect when they're not blocked by piles of dead skin cells, and as long as you stick to a daily moisturizing regimen, you should start seeing -- and feeling -- a difference almost immediately.
Like the Terminator, your stratum corneum will be back, but exfoliation isn't something you can do every day. It's a harsh process, and even people with extreme cases of xerosis shouldn't exfoliate more than once a week [source: Dermaxime].