Many people view dietary fat in a negative way, believing this necessary nutrient is a villain to be booted out of their diets. But here’s the thing: Our bodies need dietary fat to function properly and stay strong and healthy.
Beyond its nutritional importance, however, fats in our diet also contribute to the pleasure we get from eating. Fats give foods such as chocolate, peanut butter and ice cream their creamy texture. In addition, fat makes baked goods mouthwateringly moist and transforms bland animal flesh into sizzling, succulent morsels of meat.
What’s more, fats slow the digestive process, which helps us feel full and satisfy our hunger. Another role of fat in the diet is to help the body absorb certain nutrients from food, including vitamins A, D, E and K.
“These vitamins cling to fat molecules, so we need to make sure that we have adequate fat in our diets,” says Felicia Stoler, a registered dietician, nutritionist and author of Living Skinny in Fat Genes: The Healthy Way to Lose Weight and Feel Great.
Indeed, Stoler stresses that fat is essential for our health and well-being. For example, she explains, “We know that fat intake in the first two years of life are the most important aspect of making sure that myelin sheaths—the insulating layers around nerve fibers—are formed correctly.” (Myelin sheaths are primarily composed of lipids, or fats, and cholesterol, a unique type of fat.)
Our cultural demonization of fat began when an American researcher named Ancel Keys presented a hypothesis at a meeting of the World Health Organization in 1955. Keys claimed fat raised cholesterol levels that resulted in a higher risk of heart disease. “Initially, Keys targeted dietary fat as the culprit, but over time, he modified his argument to point the finger solely at saturated fat,” explains Mark Hyman, MD, on his website, drhyman.com. Hyman is a practicing family physician and best-selling author of a slew of books about nutrition, including his latest, Eat Fat, Get Thin. Keys, Hyman continues, claimed “unsaturated fat in vegetable oils could benefit health while saturated fats create adverse affects.”
In general, there are three types of dietary fats in foods we eat each day: unsaturated, saturated and trans fats. Unsaturated fats are liquid at room temperature and include both monounsaturated and polyunsaturated fats. Monounsaturated fats are found primarily in plant oils, such as olive, peanut, canola, almond, macadamia, pistachio, cashew and avocado. Polyunsaturated fats are found in sunflower, corn, soybean, flaxseed, walnut and fish oils. “We know olive oil is an important part of a Mediterranean diet and is loaded with monounsaturated fatty acids, which are really beneficial,” Stoler says. “But olive oil can’t be the only oil that you eat, so I recommend people consider using different oils, such as sustainable Malaysian palm fruit oil, which has been a key ingredient in many supermarket products. What we know about this oil is that it’s been a replacement for trans fats in a lot of processed foods because of its diversity as an oil, its ability to prevent spoilage and its ability to withstand high temperatures during cooking.” (But we also know palm oil that’s not harvested sustainably can contribute to deforestation and the loss of habitats for many endangered species, such as orangutans, the Sumatran tiger and proboscis monkeys.)
Unlike unsaturated fats, saturated fats stay solid at room temperature. These fats are primarily from animal sources, such as beef tallow, veal, lamb, pork, lard and poultry fat. They’re also found in butter, cream, milk, cheeses, and other whole milk dairy products. In addition, some plant oils, such as coconut, palm and palm kernel, also yield saturated fats. These tropical oils also include cocoa butter, a yummy-smelling fat that’s a tasty ingredient of chocolate.
Among many misconceptions about fats to avoid and fats to eat, is the idea that all saturated fats are bad. Not true, Stoler says: “Saturated fats from plants are very different than saturated fats from animals.”
In addition, findings from several recent studies suggest that we can boost our health by eating saturated fats from certain animal sources, such as eggs, grass-fed and organically raised chickens and cows, and wild-caught fish.
The takeaway is this: Fats in general are good and healthy. But some fats are better than others. Today, consumers enjoy an enormous selection of healthy oils to use for cooking that can be used for a variety of culinary needs.
“I have avocado oil, nut oils, blended oils, flavored olive oils, palm fruit oil, canola, safflower and sunflower oils,” Stoler says. “But even though olive oil is great for certain types of foods, I wouldn’t put it in a cake or a cupcake. For a sweet dish, I would use maybe Malaysian palm fruit oil because that has more of a buttery texture and taste, and more of a neutral flavor profile.
“If you’re looking for an oil with a nutty flavor, for example, I like truffle oil,” she continues. “I like the flavor of the mushrooms and I use just a little bit of it sometimes when I’m cooking to add that flavor.”
Stoler encourages using good sources of flavorful oils. With them, savvy cooks can whip up dishes to please their palates or those of family and friends. “Maybe I’d use coconut oil if I were baking because it’s got sort of a sweet flavor, but the key is to recognize that some oils have very distinct flavors,” she says. “I know some people who like to use coconut oil when they’re making eggs, but that combo doesn’t do it for me.”
Stoler also suggests cooks try chia seed oil. “Chia has omega-3 fatty acids and it’s one of few vegan sources of this essential fatty acid for those who don’t want to eat fish,” she says.
Omega-3 fatty acid, or linolenic acid, is one of two essential fatty acids (EFAs) that must be attained from foods because the body cannot make them. The other is linoleic acid, or omega-6 fatty acid. These EFAs are responsible for a number of biological functions, including blood pressure regulation, blood-clot formation and immune response to disease. In contrast, the body can make non-essential fatty acids by synthesizing other nutrients, such as carbohydrates.
The last type of fat, trans fat, a.k.a. partially hydrogenated oil, is the real villain in foods. This fat occurs naturally in some foods, but the artificial kind is man-made and used in baked goods, margarine, and snack foods. Manufacturers use trans fats to lengthen the shelf life of foods and improve their taste and texture. But the unappetizing side to trans fats is that they lower your HDL, or good cholestersol, and raise your LDL, or bad cholesterol.
Stoler says, “Sometimes, we only associate fat with high cholesterol levels and excess body weight. But fat is the most efficient way for us to store extra energy.”
Indeed, the right fats contribute to tasty meals, food satisfaction and energetic, healthy bodies; the wrong ones don’t. Remember, Stoler stresses, fat is an essential nutrient that we need to eat: “It is a myth that if you eat fat, you’ll be fat.”