If you're concerned about your fat intake, and want to make sure the oils you cook with are good for you, you're in luck! All cooking oils are healthy.
Some are healthier than others, and we'll get to that. But the real health menace is when it comes to fats that are the so-called "trans fats," which can contribute to all kinds of ailments, from heart disease to stroke to diabetes.
And while plenty of foods, especially packaged foods, have trans fats in them, there's no such thing as a liquid cooking oil with trans fat. That means there are no unhealthy cooking oils.
Most cooking oils are likewise very low in saturated fats. Saturated fats include animal fats like lard, dairy products like butter and cheese, and vegetable fats like palm oil and coconut oil. While not as bad as trans fats, saturated fats are associated with heart disease. All oils (i.e. fats that are liquid at room temperature) have at least some saturated fat in them, ranging from 6 percent (canola oil) to 18 percent (peanut oil).
Cooking Oils: The Good and the Better
What's left are monounsaturated fats and polyunsaturated fats, both of which are good for you. Every cooking oil you can pour contains these two fats. Some, like olive oil, avocado oil, and canola oil, are higher in monounsaturated. While others, like corn oil, sunflower oil, and safflower oil, are higher in polyunsaturated.
This second group, the polyunsaturated, are the so-called "good fats" that increase your HDL (the "good" cholesterol) and lower your LDL ("bad" cholesterol).
But either way, when selecting a cooking oil, your choices run from healthy to very healthy. Thus, you can select a cooking oil solely according to its culinary properties - mainly its flavor and its smoke point (i.e. the temperature at which the oil starts to smoke).
An oil with a high smoke point is better for sautéing because it can be heated to a higher temperature before smoking. Low smoke point oils are less suitable for sautéing, but can be used in salad dressings, dips, and other low- or no-heat applications.
Notwithstanding any of the above, remember that all oils and fats contain exactly the same amount of calories: nine per gram. So if you're concerned about your weight, olive oil packs the same number of calories as butter or lard.
The figures in parentheses represent the proportions of monounsaturated, polyunsaturated, and saturated fats, respectively, in each one.
Avocado Oil (70/20/10)
Made by extracting the oil from actual avocado pulp (not the seeds) and, depending on how refined it is, it has a very high smoke point of between 480 and 520 F. On the other hand, it will cost you a pretty penny. Despite its high smoke point, the subtle, yet distinctive, flavor of avocado oil is best appreciated in salad dressing or drizzling it over grilled veggies, rather than actually sautéing in it.
Canola Oil (62/32/6)
Canola has the lowest ratio of saturated fats of any cooking oil, so it is arguably the healthiest cooking oil, at least by that measurement. Its smoke point of 460 F makes is suitable for any kind of high-heat cooking, and its mild flavor won't overpower other ingredients. It's also an excellent choice for making homemade mayonnaise.
Corn Oil (31/53/16)
With over half of its fat coming in the form of polyunsaturated fats, corn oil is another solid choice for cooking, as it has a smoke point of 450 F. Its medium flavor will also suit salad dressings as well as breads and cakes that call for liquid oil (like some quickbreads and waffles, for instance).
Grapeseed Oil (17/71/12)
This is a wonderful oil with a high smoke point and high levels of polyunsaturated fat, but unfortunately its shelf life is depressingly short. What happens is that it oxidizes, causing it to develop a rancid flavor. Even unopened, a bottle of grapeseed oil has a shelf-life of no more than three months, and once the bottle is opened, it's even shorter.
Olive Oil (77/9/14)
When it comes to flavor and versatility, extra virgin olive oil is a must in every kitchen. Its flavor will vary, and while its smoke point is medium, you can still cook with it. But where it really shines is in dressings, dips, and drizzled on anything from bread to ice cream.
Peanut Oil (49/33/18)
A slight nutty flavor and high smoke point (450 F when refined) make this a wonderful oil for stir-frying. This is one of the few cooking oils where you will actually taste the oil in your finished product.
Safflower Oil (15/75/10)
Sourced from the seeds of a flowering plant called a safflower, this might be the best all-around cooking oil. If you buy only one, we recommend buying this one. Completely colorless and flavorless, it's a perfect cooking medium, and with a smoke point above 500 F, when refined, it's ideal for sautéing.
Sesame Oil (40/46/14)
Produced from sesame seeds, this oil has a low smoke point, making it a poor choice for sautéing or stir-frying. Paradoxically, because sesame oil is associated with Chinese and other Asian cuisines that employ stir-frying. The secret, however, is to drizzle the finished stir-fry with a tiny amount of sesame oil, rather than actually cooking the food in it.
Sunflower Oil (20/69/11)
Very similar to safflower oil, sunflower comes from sunflower seeds, and it is likewise very neutral. With a refined smoke point of 450 F, sunflower oil is a good option for high-heat cooking.
Vegetable Oil (24/61/15)
When you see vegetable oil, most likely it means soybean oil, which happens to be the most common cooking oil there is. Like canola oil, soybean oil is a good source of omega-3 fatty acids.