“Good” Fats, “Bad” Fats: A Dietary Oil Primer
By Leslie Vandever
Dietary fats add deliciousness, richness, and good, healthy nutrition to the foods we love. In the form of oils for cooking or eating, you can count on them to improve and enhance any cuisine.
But there’s far more to oils than meets the eye—and the tastebuds. They have a real drawback: they’re all high in calories (they’re fats, after all). But that means they’re high in energy, too. Used in moderation, with an eye on your waistline, they’re an essential part of a healthy diet.
Dietary oils come from many sources, including plants, nuts, and seeds. Some, like butter and lard, come from animals. Some have more nutritional and health value than others, so it’s important to understand how to best use them, from heating to eating.
Fats from animal sources are, in general, unhealthy. You’ll know them because they’re solid at room temperature. They’re high in saturated fat, which raises blood cholesterol to dangerous levels and puts you at risk for heart disease. Avoid or limit animal fats in your diet.
Avoid trans-fats—or trans-fatty acids—too. These are made when hydrogen is added to plant oils, and they’re double trouble. Labeled as “partially hydrogenated,” they include shortening and some margarines. Not only will they raise your levels of “bad” LDL (low-density lipoprotein) blood cholesterol, they lower the levels of “good” HDL (high-density lipoprotein) cholesterol. Too much LDL cholesterol clogs arteries; HDL cholesterol helps to remove it from the body.
Plant-based oils on their own are rich in mono- and poly-unsaturated fats. They are the “good,” healthy types of fat, rich in omega-3 fatty acids that neutralize cell-killing free radicals and, scientists believe, may preserve memory and aid thinking abilities later in life. “Good” fats don’t raise blood cholesterol levels. They help the body digest and absorb vitamins, too.
All dietary oils have a “smoke point:” the moment at which the oil gets hot enough to burn and produce smoke. The smoke point varies from oil to oil, but once it starts to burn, not only has the oil lost any nutritional value, it tastes downright awful. In addition, the fumes are toxic and release free radicals into the air.
- almond oil has a nutty flavor and high smoke point. It’s best for searing, browning, and deep frying.
- canola (rapeseed) oil has no flavor, a medium high smoke point, and can be used for frying, browning, searing, in dressings, and in some baked goods.
- peanut oil has a medium-high smoke point. Its mild, nutty flavor makes it great for stir-frying.
- safflower oil has a high smoke point, no flavor, and it’s good for searing, browning, frying, and in dressings.
- sesame oil has a medium smoke point and a rich, nutty flavor. It’s best for light sautéing.
- sunflower oil has a high smoke point, making it good for frying, browning, and searing. (Look for the high-oleic acid type, which is higher in monounsaturated fat than the others.) Its flavor is neutral.
- “light” olive/refined olive/extra-virgin olive oil has a high smoke point, so it’s good for frying, sautéing, browning, and searing. The distinctive flavor is excellent in Italian and other Mediterranean foods.
- soybean oil has a medium smoke point. It’s high in omega-6 fatty acids and works well for frying, sautéing, and browning. It’s also great for salad dressings.
- corn oil has a medium smoke point, little flavor, is rich in omega-6 fatty acids, and works well for frying, grilling, and baking.
- grapeseed oil has a medium-high smoke point, a neutral flavor, and is also rich in omega-6s. Along with using it for frying and baking, it’s delicious drizzled on crusty bread and in dressings.
Finally, a word about ghee: a traditional staple in Indian cuisine, ghee is made from the fats in whole milk and is rich in saturated fat, which has been proven to increase the risk of heart disease. The research on ghee’s health benefits is limited, but some researchers assert that if eaten as less than 10 percent of a day’s total calories, ghee may actually lower cardiovascular risks. Use it in moderation.
LeslieVandever is a professional journalist and freelance writer with more than 25 years of experience. She lives in the foothills of Northern California where she writes for Healthline.