If you're concerned about the way your skin is aging, rest assured that a great deal of your skin's fate is under your control. Skin age is determined by evaluating a number of lifestyle choices, such as diet, exercise, alcohol consumption, smoking and sun exposure.
How much time your skin spends unprotected in the sun has a lot to do with how quickly your skin ages. The sun can cause anything from a decrease in collagen to uneven skin tone, so be sure to use a sunscreen at all times when you're outdoors. Even stress can take its toll on your skin. Stress produces a hormone called cortisol, which has a tendency to decrease collagen production [source: Prevention].
To keep your skin looking young, you can eat a balanced diet rich in fruits, vegetables and unsaturated fats. Foods rich in as omega-3 fatty acids, for instance, such as fish and nuts, are particularly helpful for people with dry skin [source: University of Maryland]. Exercise helps your skin, too, by facilitating oxygen flow to keep it firm [sources: Janes].
Most resources that assign a number to your skin age will take into account your lifestyle and then provide skin care advice based on what decade your skin's age falls into. If your skin is in its 20s or 30s -- no matter what your real age is -- you'll want to focus on preventing signs of aging. If your skin is older and you want it to look younger again, you'll want to focus on repair.
For lots more information on skin age and skin care, follow the links on the next page.