Healthy Cooking Oils

Olive, Corn, Canola, Sunflower, Peanut, or Coconut? Cooking Oil Myths Revealed

Open your cupboard door, and I'm guessing you'll see at least three different bottles of cooking oil, and possibly many more. Is it any wonder you're confused? After years of new -- and sometimes conflicting -- health claims about cooking oils, most of us have switched our recipes around so many times we no longer know which to use when. (And which to toss altogether.)

Here, a guide to the six most common cooking oils, in the order of "healthiness," along with six common myths debunked.

Why Olive Oil Is Good for Your Health

Olive oil reigns supreme as the healthiest oil to cook with because it's highest in monounsaturated fat, which lowers LDL, the so-called "bad" cholesterol. Olive oil is also the richest of all the oils in omega-3 fatty acids, which help keep arteries clear and boost brain function.

Best for: Flavor
The Italians use olive oil to dip or drizzle with practically everything, for good reason. Its distinctive taste adds a welcome dose of flavor to vegetables, sauces, and even bread.

Myth: Olive Oil Has No Saturated Fat
It sure would be simpler if this were true, but unfortunately the science of fat is a pretty complicated subject. According to Harvard Medical School's Harvard Health Letter, there are actually 24 different saturated fats. Some, like those from meat and dairy, are bad for you, raising cholesterol and blood lipids; others lower cholesterol levels. Olive oil actually contains 13 percent saturated fat, more then some other oils, but it's good saturated fat rather than bad saturated fat. (Another good saturated fat is stearic acid, the type found in dark chocolate.)

Why Safflower and Sunflower Oils Are Good for Your Health

The oil from sunflower seeds and its lesser-known relative the safflower are high in monounsaturated fats and polyunsaturated fats and low in saturated fats, the ratio you want in heart-healthy oils. According to the American heart and diabetes associations, polyunsaturated fatty acids (PUFAs) have important health benefits as a rich source of omega-6 fatty acids. The problem comes with the tendency of omega-6 fatty acids to unbalance even more important omega-3 fatty acids.

Best for: Sautéing and Frying
Safflower and sunflower oils have a higher "smoke point" (the temperature at which an oil begins to smoke) than olive oil, making them good choices for cooking over high heat. Once an oil begins to smoke, the omega-3 acids begin to break down and turn to unhealthy trans-fatty acids. Chose those labeled "high-oleic," which are healthier and can withstand higher heat without smoking.

Myth: Oils Go Bad Quickly When Exposed to Air
It's true as far as it goes: Oils high in polyunsaturated fatty acids (PUFAs), like safflower, sunflower, and canola oil, can become oxidized when exposed to oxygen or heat, at which point they can be bad for you. However, most of us keep our oils capped, and most of the cooking oils sold in grocery stories are refined by processes that prevent oxidation and raise the cooking potential. One exception is when frying on high heat, when it's a good idea to use peanut oil.

Why Canola Oil Is Good for Your Health

Ever wonder why you've never heard of a canola plant? Canola oil is actually made from rapeseed, a member of the mustard family, which was genetically bred in the 1970s to produce a milder-tasting seed. A bit of history: The name was originally a trademarked derivation from "Canadian Oil, Low Acid," a name it was given by its creators at the University of Manitoba, but it's now a generic term. Canola oil also has a relatively high heat tolerance for frying, particularly "high-oleic" canola oil, which doesn't start smoking until it hits 475 degrees. (Regular canola oil's smoke point is 400 degrees.)

Best for: Baking
Of all the liquid oils, canola oil is popular for baking precisely because it has almost no flavor. After all, you don't really want your cookies or bread tasting like olives or peanuts "“ unless, of course, you're making peanut butter cookies.

Myth: Canola Oil Is Healthier Than Olive Oil
Nope, sorry, canola oil has less monounsaturated fat than olive oil, and this point is the one that matters the most. However, it's also true that canola oil is richest in alpha-linolenic acid (ALA), an omega-3 fatty acid important to cardiovascular health. The best advice is to keep both in your kitchen. Use olive oil on vegetables and when you want its distinctive flavor, canola when you want a milder choice.

Why Peanut Oil Is Good for Your Health

Peanut oil sounds wonderfully natural, since it's derived from nuts. And it is high in monounsaturated fats. However, peanut oil also contains about 30 percent polyunsaturated fat and about 20 percent saturated fat, making it fourth in line for health benefits.

Best for: Frying and Storage
Restaurants use peanut oil for frying and deep frying because it doesn't smoke or burn, even at very high temperatures. Peanut oil also has a longer shelf life than other oils.

Myth: Frying Makes Oils Bad for You
It's not frying per se that makes oils turn bad, but smoking, which releases substances that can be carcinogenic. Because peanut oil does not begin to smoke until it's hotter than 475 degrees, it's an excellent choice for safe frying.

Why Corn Oil Is Good for Your Health

Of all the so-called healthy oils, corn oil has the lowest percentage of monounsaturated fat (the healthiest type) at 24 percent, so it should be the last oil of choice for those looking to eat a heart-health or diabetes-friendly diet. Corn oil contains primarily polyunsaturated fats, rich in omega-6 fatty acids -- but most of us get plenty of omega-6 fatty acids from our daily diets, and too much omega-6 can overbalance the more important omega-3 fatty acids. Corn oil also contains small amounts of trans fats, considered the unhealthiest type.

Best for: Frying if You Don't Have Peanut Oil
Refined corn oil has a smoke point of 450 degrees, so it's better than canola oil if that's all you have.

Myth: All Vegetable Oils Are Equal
Corn and canola oil are often listed together, but while they both start with C, they aren't equal in health benefits. Because corn oil contains no omega-3 fatty acids at all, it has fewer health benefits than its rivals.

Why Coconut Oil Is Good for Your Health

Pure, unrefined coconut oil has become the darling of the natural food set, touted for its nutritional benefits and as a weight-loss aid. Coconut oil is different than other oils in consisting of more than 50 percent medium chain fats, which the body burns faster, making them less likely to be stored as fat. However, the few small studies that have been done have not shown coconut oil to have a significant effect on BMI or body weight, though there was a small decrease in belly fat. The news isn't all good, though; health organizations such as the American Heart Association and the Academy of Nutrition and Dietetics are wary of coconut oil because it's 90 percent saturated fat -- compare that with butter, which is 64 percent saturated fat, and lard, which is 40 percent saturated fat. And reports that coconut oil prevents Alzheimer's are misleading; the one small study done found an increase in memory benefits after 45 days, but no effect at 90 days.

Best for: Baking and beauty
Pure unrefined coconut oil (the kind you want) is solid at room temperature, making it useful as an alternative to saturated fats like butter or lard for baking. It can also be whipped up for icings and frostings. Coconut melts and becomes a clear liquid at 76 degrees, but it has a smoke point of 350 degrees, so it works well for sautéing vegetables, where it adds a nutty flavor. (However, olive oil is still a much healthier sauté choice.) A traditional hair and skin remedy in India and other parts of Asia for centuries, melted coconut oil makes an excellent hot oil treatment for hair or a hand and skin softener.

Myth: All Saturated Fats Are the Same
Recent studies have shown that not all saturated fats behave the same in the body. Unlike animal-derived saturated fats, the saturated fat in coconut oil is formed primarily from lauric acid, and it boosts levels of "good" HDL cholesterol when digested. However, experts still suggest using coconut oil sparingly, primarily as a butter replacement.