I was getting my hair done the other day, and the stylist (knowing I’m a nutritionist), begins to tell me how she has stopped using olive oil and replaced it with coconut oil because she is hearing that it is so much healthier. I begin to tell her that what she has heard is more fad than truth and that the type of oil you use depends more on what you are cooking. With so much misinformation in the marketplace (since it really boils down to what sales team has the media spotlight for the moment), I figured it would be a good idea to explain the different kinds of cooking oils and when you should use them.
First it is important to know that fats do not boil. At high temperatures, fats decompose and can burn, forming a smoke. We call this “smoke point” and we use it to determine what kind of fat to use for cooking, since each fat has a different smoke point. For example, butter has a low smoke point (meaning it burns easily). This is why if you have ever sautéed meat or anything else in butter, you notice it turns brown (burns) fast. Ideally, you want to use the fat to cook the food, but reduce the amount of fat that gets absorbed into the food. This is why sautéing is preferable to deep-frying.
Aside from smoke point, flavor also needs to be considered when choosing the right oil. For example, dark sesame oil has a very strong taste and you would probably not want to add it to, say, an Italian dish. Dark sesame would be more suitable for Asian cooking. However, peanut has a high smoke point so is sometimes chosen over an olive oil, which has a low smoke point.
Another factor is cost. Some oils, like almond oil, have a delicate flavor and are pricier than a canola oil. The flavor of almond oil gets destroyed when heated, so to use it for cooking would be a waste. Instead, peanut oil may be preferable as it has a similar smoke point, but a bland flavor good for cooking.
And while many have heard about the great benefits of olive oil, these benefits come from consuming the oil uncooked. Once you cook olive oil, you lose the heart healthy benefits. Olive oil is not a bad choice for cooking, but it does have a low smoke point, especially if it is unrefined or extra virgin. These are better cold. Extra light olive oil has the highest smoke point of the olive oil types.
The oils in the chart are mostly refined, vegetable oils. Some people like to use coconut oil because it is considered a natural, tropical oil. Tropical oils are high in saturated fat, which give them a longer shelf life. Some companies got a way from using coconut oil when concerns arouse around saturated fats. However, in moderation, tropical oils can be a healthy part of one’s diet. This is not a reason to remove healthy fats such as from olive oil, however. Personally, I prefer extra light olive oil for my day-to-day cooking and peanut or sesame when preparing Asian dishes. Choose what works for you.