You Should Never Put Olive Oil In An Air Fryer. Here's Why
Fans of Oprah's favorite things will know all about the air fryer. In the legendary host's own words (via Oprah.com): "Fried food minus the fat? I'm in." Most dishes require at least a little bit of fat, but the model she recommends only calls for one tablespoon of oil to fry almost three pounds of food, which is a great proportion if you're watching your calorie intake, or just trying to make healthier choices. What you might not know is the oil you choose makes a big difference.
Olive oil might seem like the best one for the job; after all, it has many health benefits, from anti-inflammatory properties to protecting against strokes and heart disease (via Healthline). However, this heart-healthy fat isn't the best choice when it comes to air frying. This is because traditional olive oil typically has a lower smoke point than other, more neutral oils like sunflower or peanut oil (via The Washington Post). The smoke point isn't usually an issue when roasting vegetables in the oven, because the pan and the food are helping to absorb the heat. An air fryer, however, is designed to cook food quickly at a very high temperature, and that can cause the oil to smoke, but that's not all you need to watch out for (via Cooking Light).
The downsides to air frying with olive oil
Unfortunately, a blaring smoke alarm isn't the only potential downside to air frying with olive oil; in fact, the smoke itself could have toxic effects on your health. According to the National Institutes of Health, long-term exposure to smoke from hot oils could increase your risk of developing lung cancer. More studies are still necessary to back up the findings, but in the meantime, it's a good idea to keep the fan on, and any windows open, to encourage airflow and minimize your exposure to potentially-harmful smoke.
Finally, air frying with olive oil can cause the food itself to have a strange aftertaste because of the oil overheating and starting to smoke (via Simply Recipes). The likelihood of this increases the more oil you use, since any excess can drip down into the bottom tray and burn there, causing more smoke and therefore more of a burned aftertaste. Luckily there is a way to use olive oil in the air fryer without causing any of these downsides. Light olive oil is made by treating traditional olive oil with chemical solvents to neutralize the flavor. It's paler in color, like a peanut or canola oil, and has a smoke point even higher than some neutral oils, making it ideal for air frying and other high-heat cooking (via Bon Appétit).