Why is fat important?
A macronutrient is something we need in relatively large amounts to be healthy. Macronutrients include water, proteins, carbohydrates, and fats. Fat is associated with being harmful, but the truth is humans need fat as:
- A source of energy
- A source of essential fatty acids that our bodies cannot make
- A component of cell walls
- A way to absorb fat-soluble vitamins: A, D, E, and K
- A way to insulate our bodies and protect organs
Fat tends to be considered “bad” because it is associated with weight gain and high cholesterol. However, certain types of fat give protective benefits to the heart if appropriate portions are consumed. The key is to understand how to choose the right amount of each type of fat, so we should look closely at the ideas of total fat and each type of fat.
The dietary reference intake (DRI) for fat in adults is 20% to 35% of total calories from fat. That is about 44 grams to 77 grams of fat per day if you eat 2,000 calories a day. It is recommended to eat more of some types of fats because they provide health benefits. It is recommended to eat less of other types of fat due to the negative impact on health.
- Monounsaturated fat: 15% to 20%
- Polyunsaturated fat: 5% to 10%
- Saturated fat: less than 10%
- Trans fat: 0%
- Cholesterol: less than 300 mg per day
Saturated fats are generally solid or waxy at room temperature and come mostly from animal products, with the exception of tropical oils. Taking in too much saturated fat is linked with raising levels of “bad” LDL cholesterol in the blood and increasing internal inflammation. Healthy adults should limit their saturated fat intake to no more than 10% of total calories. For a person eating a 2000 calorie diet, this would be 22 grams of saturated fat or less per day. If you have elevated LDL cholesterol levels, it is recommended to reduce saturated fat intake to no more than 7% of total calories. Foods high in saturated fat include:
- Beef, pork, lamb, veal, and skin of poultry
- Hot dogs, bologna, salami
- High fat dairy products, such as, cream, ice cream, whole milk, 2% milk, cheese, 4% cottage cheese
- Butter, lard, bacon fat
- Tropical oils, such as palm, palm kernel, coconut oil
- Baked goods, such as cookies, pastries, croissants
Trans fatty acids are formed when a liquid fat is changed into a solid fat through a process called hydrogenation. Many manufacturers use hydrogenated oils as an ingredient because it extends the shelf life and consistency of foods. Trans fat will raise levels of “bad” LDL cholesterol and decrease levels of “good” HDL cholesterol. There are no safe levels of trans fat to eat each day, so try to avoid trans fat completely. Even if a food is advertised as “trans fat free,” it can still contain small amounts of trans fat. Therefore, avoid foods that list partially hydrogenated oils as ingredients. Sources of trans fat include:
- Solid margarine
- Powdered coffee cream, liquid flavored coffee cream
- Convenience foods, such as certain brands of pre-packaged baked goods
Cholesterol is made by the liver. Therefore, only animal-based foods contain cholesterol. If your cholesterol levels are normal, limit your intake to up to 300 mg per day. If you have been diagnosed with high cholesterol, limit your intake to less than 200 mg per day.
These fats are usually liquid at room temperature. Sources include monounsaturated and polyunsaturated. When used in place of saturated fat, monounsaturated and polyunsaturated fats help lower cholesterol levels.
These fats come from plant-based sources and include:
- Olive, canola, and peanut oils
- Nuts and nut butters
These fats come from plant-based sources and include:
- Safflower, sunflower, corn, soybean, and cottonseed oils
Omega-3 fats are a type of polyunsaturated fat that have heart protective benefits and are associated with lowering inflammation in the body. Cold-water fish, such as salmon, tuna, herring, and anchovies, contain omega-3 fats. Plant-based sources of omega-3 fats include flaxseeds, chia seeds, and walnuts.
What is the relationship between fat intake and weight?
Being overweight may increase your risk of developing high blood pressure, diabetes, cardiovascular diseases (diseases of the heart and blood vessels) and certain forms of cancer. Therefore, it is important to lose weight if you are overweight.
It is true that a diet high in fat can lead to weight gain. The reason behind this is that a gram of fat has about twice as many calories per gram as carbohydrates and proteins. Losing weight takes more than just eating low-fat foods. You must also watch how many calories you eat and become familiar with appropriate portion sizes.
Since sources of fat are more calorie-dense, it is important to understand what a serving of a fat is equivalent to. For example, one teaspoon of butter, margarine or mayonnaise is one fat serving. For times when you may not have a measuring spoon available, a visual equivalent of one teaspoon is the tip of your thumb. See below for examples of serving sizes for added fats.
One fat serving is 45 calories, 5 grams of fat:
- 1 tsp oil, butter, margarine, or mayonnaise
- 1 Tbsp salad dressing or cream cheese
- 1 Tbsp reduced-fat mayonnaise or low-fat spread margarine
- 1.5 to 2 Tbsp reduced fat cream cheese or reduced-fat salad dressing
- 1 Tbsp seeds (pumpkin, sesame, sunflower)
- 16 pistachios
- 10 peanuts
- 6 almonds, cashews, or mixed nuts
- 4 pecans or walnut halves
- 2 Tbsp avocado
- 1.5 tsp natural peanut butter
- 8 to 10 olives
- 2 Tbsp half and half
If you look at the sources of fat listed above and you think you consume added fat and/or high-fat foods with most meals and snacks, try following the tips to help you control your intake of fat.
When selecting foods:
- Learn about the foods you eat by reading nutrition labels. When selecting food, balance those with a higher fat amount against those with a lower fat amount to stay within your fat total or "budget" for the day. Consider choosing “low-fat,” “reduced fat,” or “nonfat” dairy products to reduce your intake of less healthy saturated fat.
- Choose skim or 1% milk.
- Enjoy low-fat cheeses (no more than 3 grams of fat per ounce).
- Choose lean meats, fish, and poultry. Limit your portion of protein to about the size of the palm of your hand or a deck of cards. Other good low-fat sources of protein include egg whites, dried beans and peas, and tofu.
- Choose mono and polyunsaturated toppings in your salad such as oil & vinegar dressing, nuts, seeds, olives, or avocado in place of high saturated fat foods like cheese, bacon, and creamy dressings.
- Try hummus, guacamole, or Greek yogurt dips for your veggies, whole wheat crackers or corn tortilla chips. Hummus and guacamole can also be used as a spread on sandwiches in place of mayonnaise.
- Measure your portion of cream or half and half in your coffee to assess your portion size. Aim to cut back if you use more than 1 tablespoon per cup, or try using 2% milk instead.
When preparing foods:
- Trim all visible fat and remove the skin from poultry.
- Refrigerate soups, gravies, and stews, and remove the hardened fat before eating.
- Bake, broil, or grill meats on a rack that allows fat to drip from the meat. Avoid frying foods.
- Sprinkle lemon juice and herbs/spices on cooked vegetables instead of using cheese, butter, or cream-based sauces.
- Try plain, nonfat, or low-fat yogurt, and/or salsa on baked potatoes rather than sour cream. Reduced-fat sour cream still contains fat, so you should limit the amount you use.
When dining out:
- Choose simply prepared foods such as broiled, roasted, or baked fish or chicken. Avoid fried or sautéed foods, casseroles, and foods with heavy sauces and gravies.
- Request that your food be cooked without added butter, margarine, gravy, or sauces.
- Request salad with oil and vinegar or salad dressing on the side.
- Select fruit, angel food cake, nonfat frozen yogurt, sherbet, or sorbet for dessert instead of ice cream, cake, or pie.
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