Which cooking oil should I use?

and are there "bad" ones?

I don’t have an air fryer, but one of my qualms about them is that they use very little oil. I know what you may be thinking - but oils are “bad” anyways! Less oil and fat is better! But this thought hurts my dietitian heart, and that’s because some plant oils are wonderfully health-promoting and we should be including them in the diet regularly. As per usual, there is a TON of misinformation floating around the internet and social media about various cooking oils, so I thought I would break things down a bit.

Photo by Roberta Sorge on Unsplash

Olive oil
Olive oil is my favorite superstar oil. It’s rich in monounsaturated fats, especially oleic acid, which is important for cardiac health, reducing inflammation and may help lower LDL and total cholesterol. Consuming a Mediterranean-style diet rich in olive oil may also help reduce risk of breast cancer, and something I emphasized often during my time as a clinical breast cancer dietitian. Extra virgin oil is the least processed form of olive oil, the most nutritious because of its antioxidant content, and the best tasting. Olive oil can be used for sautéing and frying at medium-high heat, roasting (I LOVE roasting veggies with olive oil) and is also excellent in salad dressings because of its delicious flavor.

Canola oil
Ok, I get that canola oil has sort of a bad reputation. I think it’s partly because it is considered “refined”, meaning it goes through more chemical processing during production. It’s also high in linoleic acid, which is an omega 6 fatty acid. Omega 6 fats are essential fatty acids; however, when consumed in disproportionately higher amounts than omega 3 fatty acids, are considered to be inflammatory. The typical Western diet is much higher in omega 6 fats as compared to omega 3 fats (from whole foods like fatty fish, walnuts, flax seeds), due in part because canola oil can be found in a large variety of processed foods. Canola oil can be used for high heat cooking, and has a mild, neutral flavor that can be used in a variety of dishes.

Avocado oil
I would probably consider avocado oil to be the “trendiest” oil. It’s pressed from avocados, and like olive oil, is high in the heart healthy monounsaturated fat oleic acid. Avocado oil is also rich in vitamin E, a powerful antioxidant. Avocado oil has a higher smoke point compared to olive oil, and may be better suited for high heat cooking. It also has a nice flavor if used as a salad dressing base.

Coconut oil
Are we still talking about coconut oil? I’m pretty sure it’s heyday is over, but let’s review it briefly. Unlike other cooking oil, coconut consists primarily of saturated fat, which is why it is solid at room temperature. It’s a bit different from the saturated fat found in animal products like butter, because some of the saturated fats in coconut oil are a medium chain fatty acid called lauric acid. It is thought that lauric acid is absorbed more quickly by the body and used for energy, as opposed to being stored as fat. Regardless, numerous studies have found that coconut oil may contribute to elevated LDL cholesterol levels and triglycerides, and I wouldn’t consider it a heart healthy oil. I usually recommend limiting coconut oil use to when and if it makes sense. For example, it can add nice flavor to sautéed vegetables, curry dishes, and as a substitute for butter in some baking recipes.

Sunflower oil
Sunflower oil is made from pressing the oil from sunflower seeds. It is an excellent source of vitamin E, and is high in polyunsaturated fatty acids. Similar to canola oil, sunflower oil is high in omega 6 fatty acids, and when consumed frequently and in much higher amounts than omega 3 fats, can be inflammatory. Sunflower oil has a high smoke point and can be used for high heat cooking.

As always, variety is key
I always emphasize the importance of variety in the diet, and feel similarly about cooking oils. It’s always important to take into account what you’re making, flavor profiles and level of heat you’re cooking with when deciding which oil to use. That said, olive oil has the most scientific research backing its numerous health benefits. In my opinion, it’s the nutritional queen of cooking oils, and I recommend it be a staple in most kitchens.