Dietary fats and oils are found in virtually all foods. Butter and lard are fats from animals, while cooking and salad oils come from seeds, nuts, fruits, and vegetables. Fats and oils belong to a group of substances called lipids, which are biological chemicals that do not dissolve in water. The difference between fats and oils is that fats are solid at room temperature, while oils are liquid.
Fats and oils enhance the flavor and texture of foods and make cooking easier. Most people enjoy what’s known as the satisfying rich, creamy “mouthfeel” of fats, which is one reason why certain foods like ice cream and chocolate are so appealing.
Fats and oils: nutrition
Fats and oils are made up of basic units called fatty acids, with each particular type of fat or oil a mixture of saturated and unsaturated fatty acids. Unsaturated fats are further classified as either monounsaturated or polyunsaturated. All food fats, without exception, are mixtures of saturated, unsaturated, and polyunsaturated fatty acids.
Within these categories, some specific fatty acids promote good health while others do not. Saturated fat, mostly from animals, can raise levels of LDL (“bad”) cholesterol, although this does not inevitably lead to increased heart disease.
When compared to saturated fat, unsaturated fats lower total and LDL cholesterol. Health experts agree that substituting foods rich in monounsaturated and polyunsaturated fats for saturated fats helps to decrease LDL cholesterol levels and thus reduce the risk of heart disease.
For a full listing of nutrients, check the National Nutrient Database:
A word on trans fats
To make vegetable oils solid at room temperature, manufacturers once routinely added hydrogen to oils. These “hydrogenated” oils, also called trans fats, were used to make margarines and shortening and to prolong the shelf life of crackers, cookies, chips, and other foods. Studies have shown that trans fats contribute to the buildup of plaque inside arteries. The FDA requires trans fats to be listed on labels, and has said that they are no longer generally recognized as safe (GRAS). As a result of the FDA’s steps, trans fats are no longer used in large amounts in US food processing.
Types of Fats and Oils
The debate over which fats and oils are healthy versus unhealthy has gone on for decades. In general, saturated fats from animals tend to be less healthy, while monounsaturated and polyunsaturated oils are good for us (in moderation).
9 healthy ways to use oils in cooking
- Replace some or all of the melted butter in a baking recipe with avocado oil.
- Instead of sautéing vegetables in butter, steam them and then drizzle some flavorful nut oil on top.
- For a butter that’s lower in saturated fat, soften butter and beat it together with olive oil or any of the other flavorful oils. Store in the refrigerator and use as you would butter.
- Replace the butter in your mashed potatoes with olive oil.
- Use avocado oil, walnut oil, hazelnut oil, or pistachio oil in a pasta salad.
- Substitute a small amount of roasted sesame oil for tahini (sesame seed paste) in hummus recipes.
- Drizzle pumpkin seed oil over baked, broiled, or steamed fish.
- For added flavor, use a fragrant nut oil in a carrot cake recipe.
- Steep herbs or spices in a mild oil and use it for sautéing.
Published March 31, 2016