They say that 40 is the new 30, and I hope they're right, because, for me, that milestone birthday is less than five years away. There isn't much that you can do to stop the march of time. But there are ways to stop the effects of aging on your body, and eating highly nutritious foods is one of those ways.

A nutritious diet supplies your body with vitamins, minerals, antioxidants, phytochemicals, and fiber, all things that you need to stay healthy and strong. And junk foods -- such as those that are high in fat, sugar, and salt -- put you at risk for heart disease, diabetes, and obesity. Just imagine at your next birthday if someone added extra candles to your cake! Eating an unhealthy diet might just add years to your life.

To find out if your diet is helping maintain your "nutritional age," check out this quiz from eDiets. After you answer the questions, find out how to make better choices about what you eat each day.