Dr Edward F. Group
When it comes to the cooking oil in your cupboard, plant-based oils made from fruit, seeds, nuts, and grains are the way to go. From familiar olive oil to exotic macadamia oil, plant-based oils can be rich and flavourful or light and neutral. You can use them for sautéing, frying, baking, roasting, and drizzling on salad. However, not all cooking oils are created equal. They all offer different benefits (or detractions) to your health. And depending on your intended use, some work better for high-heat cooking, while others are better for low-temperature baking or salad dressings. Here is what you need to know to make the best choices for your health.
Why Using Healthy Oil is Important
Our bodies require three types of macronutrients: proteins, carbohydrates, and fats. Cooking oil, which is liquid fat, is a convenient source of fatty acids, the building blocks of fats. They help with vitamin absorption, energy storage, and controlling inflammation. You need the right balance of essential fatty acids in your diet. Alpha-linolenic acid (ALA), an omega-3 fatty acid, and linolenic acid, an omega-6 fatty acid, can only be obtained from food — including cooking oils. Ideally, you should consume one omega-3 for every two omega-6s, but most people get about 16 times as many omega-6s than omega-3s.
When choosing a cooking oil, be aware of its smoke point, which typically ranges from 225 to 510 degrees Fahrenheit. When oil is overheated, its taste and nutritional value are altered. If it starts to burn, it releases free radicals into your food and toxic compounds into the air in your kitchen.
Always look for organic, GMO-free oils and avoid dangerous, ‘partially hydrogenated’ (trans) fats. Many conventional cooking oils are extracted from plants with industrial chemicals such as hexane.
Cold-pressed oil, extracted mechanically from the plant or seed using pressure, is typically healthier. Some oils are refined so they can better withstand heat, but refinement reduces nutritional value.
TYPES OF FATS AND OILS
The Nutrition Facts label on each bottle of oil lists the content of three different types of fat: saturated, polyunsaturated, and monounsaturated. We need some of each kind, but because of the links between saturated fats and heart disease and stroke, the American Heart Association recommends that you replace most saturated fat in your diet with mono and polyunsaturated fat.
Saturated Fat
Saturated fat can come from meat, lard, and dairy, as well as some plant sources like coconut and palm. The fat is solid at room temperature. Recent research is showing a role for saturated fat in a healthy lifestyle, but it should still be used sparingly because of its link to poor health.
Polyunsaturated Fat
Polyunsaturated fat tends to be higher in omega-6 fatty acids, which is linked to inflammation in the body. Healthier polyunsaturated oil choices contain more omega-3s and less omega-6s. Polyunsaturated oil is less stable than monounsaturated or saturated fat. Polyunsaturated fat can degrade in the body, leading to oxidation and cell damage. These types of fat are not typically used for cooking — especially not at higher temperatures.
Monounsaturated Fat
Oil that’s high in monounsaturated fatty acids is a staple of the Mediterranean diet, which has been shown to extend length and quality of life. They tend to be higher in omega-3s than other types of oil and usually solidify when refrigerated.
THE HEALTHIEST COOKING OILS
Most cooking oils contain all three types of fat, or at least two, but sometimes people classify them by the type they contain the most of. Here are some of the top oils I recommend for your kitchen.
Extra Virgin Olive Oil
Extra virgin olive oil (EVOO) comes from olives and contains mostly monounsaturated fat. ‘Extra virgin’ means it’s an unrefined oil in a natural state, not treated with chemicals or heated. EVOO has a rich, distinctive flavour and a smoke point of 375 degrees Fahrenheit. While you can cook with it on the stovetop, other oils may be a better choice for frying or high-heat cooking. Extra virgin olive oil contains the highest amount of health-protecting monounsaturated fatty acids of any oil, along with vitamins A, D, E, K, and beta-carotene. It’s rich in polyphenols, a type of antioxidant. Some studies have found that the compounds in EVOO have anti-cancer properties. Refined olive oil is lower quality and loses some of its antioxidants and other nutrients in processing, so stick with EVOO.
Best Uses: EVOO is great for sautéing garlic and other veggies at low heat, and it makes a delicious oil and vinegar dressing for salads. You can also use it in recipes such as pesto and ratatouille.
Avocado Oil
Avocado oil is a monounsaturated fat extracted from the fruit of the avocado tree. It has a mild, buttery taste and a smoke point of 520 degrees Fahrenheit.
Studies suggest avocado oil may help prevent diabetes and obesity. Recent research also found that adding it to a meal can boost the absorption of antioxidants called carotenoids in food. The low-carbohydrate FODMAP diet, which helps reduce symptoms of irritable bowel syndrome (IBS), makes extensive use of avocado oil.
Best Uses: Because of its very high smoke point, it is good for your highest-heat cooking and frying but can also be used cold in dips or recipes.
Peanut Oil
Extracted from peanuts, this oil is commonly used in Chinese and South Asian cuisine. It has a mildly nutty flavour and a smoke point of either 320 (unrefined) or 450 (refined) degrees Fahrenheit. Peanut oil is rich in monounsaturated fatty acids, and it is also high in polyunsaturated fatty acids and oleic acid, an omega-9 fatty acid. It’s a good source of vitamin E – one tablespoon contains 11 percent of your daily requirement. One study found that when people got half their fat intake from peanut oil, and their cholesterol levels improved compared with people who ate the standard American diet.
However because peanut oil has a higher omega-6 fatty acid content, use it in moderation and look for organic varieties.
Best Uses: Refined peanut oil is a go-to for frying and making Asian dishes. Unlike many oils, it doesn’t absorb the flavour of the food you cook it in and can be reused.
Flaxseed Oil
Flaxseed oil comes from the seeds of the flax plant. It is a neutral-tasting oil with a smoke point of only 225 degrees Fahrenheit, which means you should not use it for high-temperature cooking. Flaxseed oil has the highest alpha-linolenic acid (ALA) omega-3 content of all oils, plus some fibre and potassium. Studies have shown the omega-3s in flaxseed oil are associated with nearly a 10 percent lower risk of fatal heart attacks.
Best Uses: Use at room temperature in recipes for dips and dressings. Add a teaspoon to a fruit smoothie to boost your nutrition without changing its flavour. Many people take flaxseed oil as a supplement.
Sesame Oil
Made from sesame seeds, this oil has equal amounts of polyunsaturated and monounsaturated fats. Its nutty, fragrant flavour best complements South Asian, Middle Eastern, and African cuisine. It has a smoke point of 350 (unrefined) or 450 (refined) degrees Fahrenheit. Sesame oil has an extremely high antioxidant capacity, meaning it is good at fighting free radicals.
Although it has anti-inflammatory properties, it also has a higher omega-6 content than some other oils, so use it in moderation.
Best Uses: With its distinctive taste, a little sesame oil goes a long way. It can be a good oil for high heat cooking for people who are allergic to peanuts.
Walnut Oil
Pressed from walnuts, this oil has a rich, nutty taste. Its smoke point is 320 degrees Fahrenheit. It’s high in the essential fatty acid ALA and boasts an antioxidant called ellagic acid, which research suggests may be an important nutrient in the fight against cancer. As a good source of important nutrients, including B vitamins, vitamin E, selenium, iron, and calcium, walnut oil may even help stabilise hormone levels.
Best Uses: Walnut oil’s flavour and texture make it good for low heat uses such as baking, marinades, dressings, or on top of whole-grain pasta.
Coconut Oil
An integral part of tropical cuisine, coconut oil is extracted from coconut flesh. You can buy unrefined extra virgin coconut oil or refined coconut oil for a more neutral flavour. Its smoke point is 350 (unrefined) and 450 (refined) degrees Fahrenheit. Studies have found that, despite being 92 percent saturated fat, this oil has excellent health properties. For starters, it boosts your body’s “good” HDL cholesterol, and is rich in lauric acid – a medium-length long-chain fatty acid that resists harmful organisms, boosts metabolism, and protects brain health. Coconut oil contains medium-chain fatty acids (MCFAs), which make it easier to digest than other types of oil. On the other hand, coconut oil does raise “bad” LDL cholesterol more than unsaturated oils but less than butter.
Best Uses:Coconut oil is extremely versatile. Use the unrefined oil with the coconut when making Thai or Indian food. You can use coconut oil for frying, sautéing, baking, to grease pans, and many other uses. Some people consume a teaspoon on its own as a health supplement or add it to their coffee.
Cooking Oils to Avoid
The following oils should never find their way into your shopping:
Soybean Oil
Most soybean oil is made from genetically modified (GMO) soybeans. GMO soybean oil is rife in packaged foods – which is another reason to avoid those. Soybean oil also messes with your metabolism: A recent study suggests that compared with coconut oil and sugar, soybean oil caused more obesity and diabetes in mice.
Corn Oil
More than half of corn oil is polyunsaturated fat, and it also contains a high proportion of omega-6 fatty acids. Most corn oil is extracted with hexane, a toxic chemical solvent that may end up in the final product. Last but not least, most corn oil comes from genetically modified corn, which you should avoid altogether.
Canola Oil
Although it is polyunsaturated, most canola oil is genetically modified. Not only that, canola is heavily processed and extracted with hexane, which may contaminate the cooking oil. High heat is used during processing, which turns polyunsaturated fats rancid – or into dangerous trans fats. One study found that 0.5 to 4 percent of the oil in soybean and canola oil being sold had turned to trans fats.
Palm Kernel Oil
This oil is as bad for you as it is for the tropical forests, which are being cut down for palm plantations. Not only does it have more grams of fat per serving than other oils (22 grams vs. 14 grams), but it also consists almost entirely of saturated fat. Like soybean oil, palm oil is found extensively in packaged foods.
Cottonseed Oil
Made from seeds of the cotton plant, which aren’t edible, this polyunsaturated oil can contain residue of chemical fertilizers and pesticides used to grow the cotton. More than half of the fatty acids it contains are omega-6, and it’s higher in saturated fat than most polyunsaturated oils.
Grapeseed Oil
Not to be confused with rapeseed (which is what canola is made from), grapeseed comes from the seeds left over from wine-making. Although it is polyunsaturated, grapeseed oil also contains high levels of omega-6 fatty acids and is extracted with hexane that can leach into the oil.
‘Vegetable Oil’
You might also see products simply labelled as vegetable oil. These contain a mixture of different oils, usually soybean, canola, corn, cottonseed, and other oils that are high in omega-6 fatty acids. While it may be cheaper, avoid anything labelled as vegetable oil because it is, inevitably, processed with toxic solvents like hexane and is not a healthy choice.
POINTS TO REMEMBER
The best cooking oils are fresh, organic, and cold-pressed. They’re rich in omega-3 fatty acids and stand up to the level of heat you plan to use. Olive, avocado, and peanut oil are mostly monounsaturated fat and excellent choices. Sesame and walnut oil are also excellent choices for cooking. Flaxseed oil, which is high in omega-3 fatty acids, is a good option for low-temperature uses, like salad dressing. Coconut oil contains mostly saturated fat, but its lauric acid content provides health benefits including boosting good cholesterol.
Steer clear of hydrogenated oils such as what you find in margarine or many packaged food, because they contain dangerous trans fats. Avoid soybean, corn, palm kernel, cottonseed, canola, and grapeseed oil which likely contain GMOs or are extracted with harsh chemical solvents.
*For further information and references, please visit the below website and we would also suggest you conduct your own research.