When I'm teaching a class and we talk about the importance of vitamins and antioxidants, I use the following example. I slice an apple a couple days before class and divide the slices between two plates. I dip one batch in lemon juice.
By the time class rolls around, the untreated apple slices are brown and oxidized. This is because the sugars in the untreated apple have turned brown from their exposure to oxygen in the air. (it's the same thing as rust developing on the exposed or unprotected metal of an old car).
The treated apple, however, remains fresh, crisp, and white because it is drenched in natural antioxidants (vitamin C) found in the lemon juice. Think of the cells in the tissues throughout your body as apple slices. They're under constant attack by a type of oxygen called free radicals. Do you want the cells in your body to remain healthy fresh and intact, or do you mind if they become disfigured and damaged? This type of damage is exactly what speeds up the aging process in your body. This is the difference a vitamin and antioxidant-rich diet can make. You are what you eat! The quality of your calories is as important as the quantity
Cheryl Forberg, RD, is a James Beard award-winning chef, a bestselling author and the former nutritionist for NBC's "The Biggest Loser." 
