When it comes to weight loss, people tend to think of fat as enemy No. 1. However, all fats are not equal; while unhealthy fats should be avoided, there are healthy fats that your body needs in order to survive.
Approximately 20 to 35 percent of the calories you consume every day should be from fat; however, the USDA recommends that you limit your intake of saturated fats and trans fats.
There are four different kinds of fat, according to Harvard Health. They have similar chemical structures that consist of a chain of carbon atoms bonded to hydrogen atoms. What differentiates one type of fat from another is the length and structure of the carbon chain and the number of hydrogen atoms attached to it. These differences determine the physical properties of the molecules of fat and how healthy they are.
Unsaturated fats are the healthy types of fat. In fact, they are an essential component of a healthy diet. Fat is not only a major source of energy but also necessary to build cell membranes and the sheaths that insulate your nerves. Furthermore, fat helps your body absorb important vitamins and minerals and is required for blood clotting, muscle movement and fighting inflammation.
Unsaturated fats are usually liquid at room temperature. Monounsaturated fats and polyunsaturated fats are the two main types of unsaturated fats. Avocados, nuts, olive oil, canola oil and peanut oil are some of the foods that contain monounsaturated fats.
Polyunsaturated fats are essential fats because your body needs them but can't make them, which means you need to obtain them from your diet. The two main types of polyunsaturated fats are omega-3 fatty acids and omega-6 fatty acids. These fats lower your cholesterol levels and help prevent heart disease and stroke.
Salmon, mackerel, sardines, flaxseeds, walnuts, canola oil and unhydrogenated soybean oil are some of the sources of omega-3 fatty acids. Vegetable oils such as safflower, soybean, sunflower, walnut and corn oils are sources of omega-6 fatty acids.
Read more: 18 Fat-Rich Foods That Are Good for You
Saturated Fats and Trans Fats
Saturated fats are common in the American diet and are commonly found in red meat, full-fat dairy products like whole milk and cheese, coconut oil and many baked goods and processed foods.
Harvard Health notes that research studies have shown mixed results on the effects of saturated fat on health; however, a diet rich in saturated fats has been shown to raise cholesterol levels and cause arterial blockages. Overall, it is recommended you limit your intake of saturated fat.
Trans fats are the worst type of fat, since they have no health benefits and no amount is safe for consumption. These fats are the byproduct of a process called hydrogenation that turns healthy oils into solids to keep them from going rancid.
Trans fats used to be found in margarine and vegetable shortening; however, they are banned in the United States because they raise your cholesterol levels and cause inflammation, which increases the risk of conditions like heart disease, diabetes and stroke.
Despite the ban, there may still be trace amounts of trans fats in your food; the U.S. Food and Drug Administration allows quantities of up to 0.5 grams of trans fat per serving to be listed as 0 grams of trans fat on food labels.
Recommended Fat Intake Per Day
The USDA's Dietary Guidelines for Americans recommends that 20 to 35 percent of the total calories you consume every day should be from fat. In a 2,000-calorie diet, for example, that works out to 400 to 700 calories from fat per day, according to the Mayo Clinic. One gram of fat equals 9 calories, so that amounts to anywhere between 44 to 78 grams of fat per day.
But there are different types of fats, so how much should you be eating of each? The Cleveland Clinic recommends that 15 to 20 percent of your total calorie intake per day be from monounsaturated fats, 5 to 10 percent from polyunsaturated fats, less than 10 percent from saturated fats and 0 percent from trans fats.
Dietary Fat and Weight Loss
Fats are energy-dense foods, with more than double the calories found in carbohydrates and proteins. Eating a diet high in fat can therefore cause weight gain because your body stores the excess fat that it does not burn. It's important to be mindful of how much fat you're eating and equally important to be mindful of the type of fat you're eating.
Healthy amounts of monounsaturated and polyunsaturated fats can help you lose weight because they are filling and promote satiety. This helps with weight loss because unlike other foods like refined carbs, which cause you to crave more, foods with unsaturated fats can help fill you up and curb your appetite.
Read more: Why You Need to Eat Fat to Burn Fat
Saturated fats and trans fats are often found in highly palatable foods like cheeses, cakes, cookies, ice creams, crackers, icings, microwave popcorn, sausages, bacon, ribs and fried potatoes. These foods activate your hedonic system, which promotes greater appetite, causing you to eat more than you should, according to a November 2014 study published in the journal Advances in Nutrition.
Eating Fats Healthfully
The U.S. National Library of Medicine (NLB) notes that adding unsaturated fats to an unhealthy diet will not get you very far; instead it's recommended that you replace the unhealthy fats like saturated fats and trans fats in your diet with healthy fats like monounsaturated and polyunsaturated fats.
A couple of ways to do this are to replace butter and solid fats with olive oil or canola oil and snack on nuts instead of cookies. The portion of nuts should be small, however, since they are calorie-dense foods. A 1-ounce serving of nuts contains anywhere between 160 and 200 calories, of which 80 to 90 percent of the calories are from fat.
Just in case you were looking for another reason to eat avocado, the NLB recommends adding it to your salads and sandwiches. A 100-gram serving of avocado provides 160 calories and 14.66 grams of fat. Of the total fat content, 11.6 grams of fat are from unsaturated fats and only a small amount is from saturated fats.
The Cleveland Clinic suggests a few tips that can help you cut out unhealthy fats from your diet, like opting for lean meats, fish and poultry over red meat, trimming all visible fat from meat and poultry before you cook it and cooking meat on a rack that allows additional fat to drip away.
Furthermore, you can replace cheese, butter and cream-based sauces with garnishes like herbs, spices and lemon juice and refrigerate soups, gravies and stews before you eat them so that you can scoop off the fat that pools at the top.
- USDA: “2015-2020 Dietary Guidelines for Americans”
- Harvard Health: “The Truth About Fats”
- Mayo Clinic: “Fat Grams: How to Track Fat in Your Diet”
- Cleveland Clinic: “Fat: What You Need to Know”
- USDA: “Saturated, Unsaturated and Trans Fats”
- U.S. National Library of Medicine: “Facts About Monounsaturated Fats”
- U.S. Food and Drug Administration: “Small Entity Compliance Guide: Trans Fatty Acids in Nutrition Labeling, Nutrient Content Claims and Health Claims”
- Cleveland Clinic: “Nutrition: Nuts & Heart Health”
- USDA FoodData Central: “Avocados, Raw, All Commercial Varieties”
- U.S. National Library of Medicine: “Variety, Palatability, and Obesity”