First of all, oil isn't evil! Healthy oils are part of balanced eating. Oil makes salad dressings taste great. It adds richness to soups and stir-frys and is a must for baking. If you're doing the Fast Metabolism Diet, you should avoid all added oil for the first four days (Phases One and Two), but you can use healthy fats, including some oils, on Phase Three. But which ones should you use? The store aisle is crowded with choices, so let's break it down.

If you've only got olive oil in your pantry, you might consider adding one or two other oils. Alternative oils are getting easier to find, and they're a lot healthier than corn or canola oil.

For Sauteing And Cooking

Grapeseed oil - The light, neutral taste and high smoke point of grapeseed oil make it a great choice for cooking. Try it in baking or a stir-fry, or put its neutral taste to work as an ingredient in homemade salad dressing. Grapeseed oil costs about the same as olive oil. 

Coconut oil - Coconut helps keep your thyroid up to speed. The oil imparts a certain... well, coconut taste to everything it touches, so it's not for everybody; test the waters by trying it in stir-fry or curry, or adding it to your morning smoothie. Coconut oil is not sensitive to heat, so if you like the taste, you can even cook with it.

Olive oil stimulates your body to burn more fat as fuel, and it's high in healthy fats. Try drizzling it over salads or using it to sauté your favorite vegetables. Olive oil does impart a slight taste that most people associate with Italian food.

Safflower oil is a great source of omega-3 fatty acids that can be used for cooking or in salad dressing. Its mild flavor makes it a good choice for anyplace where you don't want an additional flavor. It can also help regulate blood glucose levels. Safflower is easy to find in stores and costs about the same as olive oil.

Sesame Oil is a good source of protein and healthy fat, and it's got lots of lysines that will help your body release fat. It also has a definite flavor and a spicy one at that. Try using sesame oil for stir-frys to give them a kick, or drizzle over buckwheat noodles.

Sunflower Oil is another neutral-flavored oil that's suitable for cooking, greasing baking pans, and so on. It's low in saturated fat and high in good-for-you unsaturated fats.

For Salad Dressings, Dips And Spreads

Grapeseed, olive oil and safflower/sunflower oils are all good choices for salad dressings, but there are a few others to consider.

Flax oil - It's rich in heart-healthy omega-3 fatty acids, one of the building blocks for fat that your body can't make on its own -- you have to take it in via food or supplements. Flax oil is also so sensitive to heat that it should be stored in the refrigerator, even when unopened. You should never cook with it, but it's great as part of your morning smoothie or as an ingredient in homemade salad dressing. Some people also love the mild, nutty taste of flax oil spread on a piece of sprouted grain toast.

Hemp Oil - Like flax oil, hemp oil is very sensitive to heat and should never be used for cooking. It's an excellent source of omega-3 fatty acids, however, and a welcome addition to your smoothies, salad dressing, or morning oatmeal.

Walnut Oil - contains more concentrated levels of omega-3 fatty acids than you'd get in straight walnuts. Its rich, nutty flavor is great over salads and with meat or fish -- but be warned that it can turn a little bitter when used for cooking.

Oils To Avoid

Soybean oil - Although it's rich in omega-3 fatty acids, soy is almost always genetically modified -- and soy is what farmers use to cheaply fatten up their cattle. Do you really want to do that to yourself?

Corn oil - Guess what else farmers use to fatten their cattle up -- and guess what else has been genetically modified to the point it's a wonder your body can even digest it? Yep, CORN!

Canola oil - Another oil that's rich in healthy omega-3 fatty acids, but the vast majority of canola plants have been genetically modified -- best to steer clear.

Wheat germ oil - You don't see it much in stores, but you'll see it on labels. Wheat is another crop that's been genetically modified until it's almost unrecognizable.

Peanut oil - This comes from a crop that's exposed to far too many agricultural chemicals -- once again, it's best to steer clear. Fortunately, there are plenty of healthy alternatives you can choose from.