When you’re prepping a meal you may use whatever oil is easiest to reach. And for the most part, it seems like you can’t go wrong. Most oils contain monounsaturated and polyunsaturated fats, which may lower “bad” LDL cholesterol levels when replacing a saturated fat like butter. Olive oil, for example, is a staple in the Mediterranean diet, and for good reason: It contains at least 30 phenolic antioxidant compounds, and regular consumption is associated with lower risk of obesity, heart disease, type 2 diabetes, and cancer (breast, colorectal, and prostate), shows Spanish research. But while certain oils, like olive, are heart-healthy, those benefits may be lost when used incorrectly.
A common mistake when cooking with oils is using a too-high heat on a low- or no-heat oil. Every oil has a smoke point, or a temperature at which smoke forms and the oil’s compounds break down, releasing free radicals, degrading nutrients, and producing a rancid flavor. “Raising the temperature to the smoke point or beyond can destroy health benefits found in oils, especially in those with omega fatty acids,” explains James Briscione, director of culinary development at the Institute of Culinary Education in New York City.
Oil degradation can also cause a food to absorb too much oil and become greasy. As for flavor, too-high heat destroys aromatic compounds in oils. This renders fine oils, like extra-virgin olive and sesame, nearly taste…