Vegetable oil shelves at the supermarket are crowded with the usual suspects (canola, olive, soybean, safflower, sunflower, peanut, corn, etc.).

But with many sporting "Cholesterol Free," "0g Trans Fat" and "Natural" on their labels, things can get confusing.

To help translate a few of those terms, we talked with registered dietitian Marisa Moore, an Atlanta-based spokeswoman for the American Dietetic Association.

Q: What does "vegetable oil" really mean?

A: Most of the time, when you see the term "vegetable oil," it refers to soybean oil. Take a look at the ingredient list and more often than not you'll see soybean oil listed as the only ingredient. If you see a combination of soybean oil plus canola oil or safflower oil, for example, it's a blend of different plant-based oils.

Q: Why do some labels say "No Cholesterol"? Isn't it found only in animal products?

A: The goal might be to attract those who are trying to lower their cholesterol who may not understand that vegetable oil doesn't naturally have cholesterol in it.

Q: Are there trans fats in vegetable oils?

A: There wouldn't be trans fats in the liquid vegetable oils. When you get into the solid vegetable oils, the partially hydrogenated ones, such as shortening products, then, yes, you will get trans fats there.

Q: What about "natural"? Is there a government definition for that?

A: Sometimes the term natural is used as a marketing tool. That may mean they haven't added anything to it. Because there's no set definition, you can't really tell.