Nutrition Spotlight: Fats

Many of us grew up being told that fat was bad and that we should choose low-fat or fat-free versions of our favorite foods. While the advice may have been well meaning, it’s one of the biggest nutrition lies that the public has ever been told. Actually, a well-balanced and nutritious diet should include a good mix of different kinds of fats.

Unsaturated fats are the healthier type. They are classified as either a monounsaturated fat or polyunsaturated fat based on the number of double bonds they contain. Sources of monounsaturated fats include olive and peanut oils; avocados; almonds, hazelnuts, and pecans; and pumpkin and sesame seeds. You can find polyunsaturated fats in sunflower, soybean, and flaxseed oils; walnuts; flax seeds, fish.  

Healthy fats really work hard in the body. They help absorb fat-soluble vitamins A, D, E and K; keep your hair and skin healthy; regulate your body’s temperature; lower cholesterol levels; and boost brain function. Because fat is digested more slowly than carbohydrates and protein, they help us feel full longer, which can promote weight loss. They can reduce inflammation and lower the risk of heart disease. And, as we all know, fat helps bump up the flavor of foods, which makes them more satisfying.

Omega-3 fats are a type of polyunsaturated fat found in flax seeds, walnuts, soybean oils, and fish. Omega-3s help make up cell membranes and make sure they function well. They are the building blocks of hormones that regulate lots of important functions, like blood clotting, contraction and relaxation of artery walls, and inflammation. Researchers are discovering their power to help prevent heart disease and stroke and maybe help control lupus, eczema, rheumatoid arthritis, cancer, and other conditions.

Saturated fat is found in butter, refined vegetable oils, processed meat, and some dairy products. Typically, registered dietitians recommend incorporating these foods sparingly. Studies have shown that replacing just 5 percent of calories from saturated fats with an equal amount from polyunsaturated or monounsaturated fatty acids resulted in a 25 percent and 15 percent reduced risk of heart disease, respectively. Getting too much saturated fat can contribute to chronic disease and weight gain.

Trans fats are the worst type of fat for your health. They are made when manufacturers turn liquid oils into solid fats, like shortening and margarine. They are created through a process called hydrogenation, which is used to increase the flavor and texture while extending the shelf-life of foods. Many fried foods, commercial baked goods, and processed foods contain trans fats. Eating too much trans fat can cause weight gain and increase risk for type 2 diabetes and other serious health problems. Foods containing trans fat should be included in your diet only very rarely if at all.

The best way to know what type of fat you are getting is to read the nutrition label on the foods you purchase. The most recent version of the nutrition label includes both grams of trans fat and saturated fat. You can subtract those numbers from the total fat to determine the unsaturated fat in the food item.

By slowly reducing the trans and saturated fats in your diet and incorporating more sources of healthy fats, you will enjoy all of the flavor and health benefits fat brings to the table.

 Kristin Irace, RD, is a registered dietitian with Southwestern Vermont Medical Center, part of Southwestern Vermont Health Care, in Bennington.