Good Fats, Bad Fats

olive oil on a spoon

What's the difference between good fats and bad fats?

"Good" fats help protect your body against heart disease; "Bad" fats pose a threat to your heart and blood vessel system.

Making heart healthy food choices and keeping a healthy body weight can help prevent and treat heart disease. Eating too much of any kind of fat is not good for your health. But when it comes to your heart, some types of fats are healthier for your heart than others. So how do you make smart choices? Learn how to recognize good fats and bad fats.

“Bad” Fats“Good” Fats
Saturated, Hydrogenated & Trans FatsMono-and Polyunsaturated Fats
Strictly limit intake:Use in moderation:
Solid at room temperatureLiquid at room temperature
Animal Fats (Saturated fats)

  • Meats, cheese, cream, butter,

  • Lard, chicken skin

Plant Oils

  • Olive, safflower, canola,

  • Sunflower, soy, peanut oils

Tropical Oils

  • Coconut and palm oils

Nuts and avocados
Hydrogenated Oils (Trans fats)

  • Stick margarines, shortening, fast-food, processed food

Omega-3 fats

  • Salmon, mackerel, herring,

  • Flaxseeds, walnuts, soybean and

  • Canola oils

Understanding Bad Fats

”Bad” fats pose a threat to your heart and blood vessel system because they increase your body’s production of cholesterol. “Bad” fats also cause clogging of your blood vessels, or athersclerosis. If there is a block in the blood flow to your heart, this can lead to a heart attack. If the blood vessels in your brain are blocked, this can lead to a stroke. “Bad” fats increase your risk for coronary heart disease, and need to be limited in your diet:

  • Saturated fats
  • Hydrogenated fats
  • Trans fats

Saturated fats, which usually come from animal sources, are naturally solid at room temperature. Examples are lard, butter, milk fat, meat, chicken and pork skin, ice cream and cheese. Beware of coconut and palm oils as well. These tropical oils contain high amounts of saturated fats.

Hydrogenated fats are created by a chemical process that turns liquid vegetable oils into semi-solid or solid fats at room temperatures. Hydrogenation sometimes turns oils into what are called trans fats, a particularly unhealthy transformation that nonetheless has become a key ingredient for packaged snacks, baked items, stick margarines, shortening and fast foods. Avoid products that made with hydrogenated or partially-hydrogenated oils. The good news is that more products on the market are “trans fats-free.” Choose these products instead.


Understanding Good Fats

Some fats don’t add to heart disease risk. When you eat “good” fats in place of “bad” fats, these “good” fats can help protect your body against heart disease by lowering your blood cholesterol levels. However, even these “good” fats are high in calories, and most will raise your triglyceride levels. You have to limit how much you eat – even if considered “good” fats. These “good” fats are:

  • Polyunsaturated fats
  • Monounsaturated fats
  • Omega-3 fatty acids

Polyunsaturated fats are vegetable oils that stay liquid at room temperature, and on the grocer’s shelves. Examples are safflower, corn, soybean, cottonseed and sunflower oils. Soft tub margarines, mayonnaise and salad dressings also contain polyunsaturated fat. Substitute these fats in place of saturated, hydrogenated, and trans fats to improve your ratio of good (HDL) to bad (LDL) cholesterol.

Monounsaturated fats are vegetable oils that also are liquid at room temperature. Examples are olive oil (and olives), avocados, canola oil, and peanut oil (and peanuts). Replacing saturated fats in your diet with monounsaturated fats can help lower LDL “bad” cholesterol without lowering the HDL “good” cholesterol.

Omega-3 fatty acids from marine sources are considered heart healthy, because they lower the level of triglycerides (or fats) and cholesterol circulating in your bloodstream. They also discourage unwanted blood clotting. Good sources are fatty fish – especially salmon, halibut, mackerel, tuna, sardines, sea bass, herring, pompano, and lake trout. Eat fish 2 to 3 times a week. Vegetarian sources of omega-3 fatty acids are flax seeds, walnuts, canola oil, soybean and soy products; however, vegetarian sources may not be as effective.

Don’t overeat fats – even the “good” ones!

What About Cholesterol?

Dietary cholesterol can raise your own blood cholesterol levels and increase your risk for coronary heart disease. So limit high cholesterol foods, and choose smart portion sizes. Cholesterol is found in ALL foods from animal sources, like meat, egg yolks, fish, shrimp, squid, poultry and dairy products. There is no cholesterol in plant-derived foods. If you have diabetes, the daily limit on cholesterol is 200 mg a day. Remember, even though a food may be low in fat doesn’t necessarily mean that it’s low in cholesterol. To keep your cholesterol in check, choose lean meats, and aim for a portion size about the size of the palm of your hand – twice daily.

Learn more about Cholesterol and Fats

View a list of the Cholesterol Content of Foods

What are Plant Stanols and Sterols?

Plant stanols and sterols block the absorption of cholesterol. Eating 2 grams of plant stanols and sterols a day may help lower “bad” LDL cholesterol and total cholesterol. Sources of plant stanols and sterols include cholesterol-lowering margarines, like Benecol and Take Control – found in the margarine section of your grocery store.

Self-assessment Quiz

Self assessment quizzes are available for topics covered in this website. To find out how much you have learned about  Understanding Fats and Oils, take our self assessment quiz when you have completed this section.  The quiz is multiple choice. Please choose the single best answer to each question. At the end of the quiz, your score will display. If your score is over 70% correct, you are doing very well. If your score is less than 70%, you can return to this section and review the information.

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