Polyunsaturated fats can have a beneficial effect on your heart when eaten in moderation and when used to replace saturated fat and trans fat in your diet.

AHA Recommendation

For good health, the majority of the fats that you eat should be monounsaturated or polyunsaturated. Eat foods containing monounsaturated fats and/or polyunsaturated fats instead of foods that contain saturated fats and/or trans fats.

What are polyunsaturated fats?

From a chemical standpoint, polyunsaturated fats are simply fat molecules that have more than one unsaturated carbon bond in the molecule, this is also called a double bond. Oils that contain polyunsaturated fats are typically liquid at room temperature but start to turn solid when chilled. Olive oil is an example of a type of oil that contains polyunsaturated fats.

How do polyunsaturated fats affect my health?

Polyunsaturated fats can help reduce bad cholesterol levels in your blood which can lower your risk of heart disease and stroke. They also provide nutrients to help develop and maintain your body’s cells. Oils rich in polyunsaturated fats also contribute vitamin E to the diet, an antioxidant vitamin most Americans need more of.

Oils rich in polyunsaturated fats also provide essential fats that your body needs but can’t produce itself – such as omega-6 and omega-3 fatty acids. You must get essential fats through food. Omega-6 and omega-3 fatty acids are important for many functions in the body.

Are polyunsaturated fats better for me than saturated fats or trans fats?

Yes. While, all fats provide 9 calories per gram, monounsaturated fats and polyunsaturated fats can have a positive effect on your health, when eaten in moderation. The bad fats – saturated fats and trans fats – can negatively affect your health.

Which foods are high in polyunsaturated fats?

Most foods contain a combination of fats.

Foods high in polyunsaturated fat include a number of plant-based oils, including:

• soybean oil
• corn oil
• sunflower oil

Other sources include some nuts and seeds such as walnuts and sunflower seeds, tofu and soybeans. The American Heart Association also recommends eating tofu and other forms of soybeans, canola, walnut and flaxseed, and their oils. These foods contain alpha-linolenic acid (ALA), another omega-3 fatty acid.

Are polyunsaturated fats lower in calories?

Polyunsaturated fats – like all fats – contain nine calories per gram.

Eating too much saturated fat can raise the level of LDL cholesterol in your blood. A high level of LDL cholesterol in your blood increases your risk of heart disease and stroke.

What are saturated fats?

Saturated fats are typically solid at room temperature.

How do saturated fats affect my health?

Saturated fats are found in animal-based foods like beef, pork, poultry, full-fat dairy products and eggs and tropical oils like coconut, and palm. Because they are typically solid at room temperature, they are sometimes called “solid fats.” Saturated fats can cause problems with your cholesterol levels, which can increase your risk of heart disease. Replacing foods that are high in saturated fat with healthier options can lower risk of heart disease.

What foods contain saturated fat?

Saturated fats occur naturally in many foods. Most come from animal sources, including meat and dairy products, as well as tropical fats like coconut, palm and palm kernel.

Examples of foods with saturated fat are:

• beef
• lamb
• pork
• poultry, especially with skin
• beef fat (tallow)
• lard and cream
• butter
• cheese
• ice cream
• coconut
• palm oil
• palm kernel oil
• some baked and fried foods

AHA Recommendation

The American Heart Association recommends aiming for a dietary pattern that achieves 5% to 6% of calories from saturated fat.

For example, if you need about 2,000 calories a day, no more than 120 of them should come from saturated fat.

That’s about 13 grams of saturated fat per day.

Remember the big picture, your overall eating pattern. Apply this general guidance regardless of where your food is prepared or consumed:

• Balance calorie intake with calorie needs to achieve and maintain a healthy weight.
• Choose whole grains, lean and plant-based protein and a variety of fruits and vegetables.
• Limit salt, sugar, animal fat, processed foods and alcohol.

What are alternatives to replace saturated fats in the foods I eat?

As part of an overall heart-healthy dietary pattern, choose lean meats and poultry without skin. Prepare them without added saturated and trans fat.
Eat foods made with liquid vegetable oil but not tropical oils. It also means eating fish and nuts. You also might try to replace some of the meat you eat with beans or legumes.

There’s a lot of conflicting information about saturated fats. Should I eat them or not?

The American Heart Association recommends limiting saturated fats – which are found in butter, cheese, red meat and other animal-based foods, and tropical  oils. Decades of sound science has proven it can raise your “bad” cholesterol and put you at higher risk for heart disease.

The more important thing to remember is the overall dietary picture. Saturated fats are just one piece of the puzzle. In general, you can’t go wrong eating more fruits, vegetables and whole grains – and taking in fewer calories.

When you hear about the latest “diet of the day” or a new or odd-sounding theory about food, consider the source. The American Heart Association makes dietary recommendations only after carefully considering the latest scientific evidence.

We know research shows that reducing trans fat in the American diet helps reduce risk of heart disease, but how and why? Let's try to clear up the confusion about trans fats.

What are trans fats?

There are two broad types of trans fats found in foods: naturally-occurring and artificial trans fats. Naturally-occurring trans fats are produced in the gut of some animals and foods made from these animals (e.g., milk and meat products) may contain small quantities of these fats. Artificial trans fats (or trans fatty acids) are created in an industrial process that adds hydrogen to liquid vegetable oils to make them more solid.

The primary dietary source for trans fats in processed food is “partially hydrogenated oils." Look for them on the ingredient list on food packages. In November 2013, the U.S. Food and Drug Administration (FDA) made a preliminary determination that partially hydrogenated oils are no longer Generally Recognized as Safe (GRAS) in human food.

Why do some companies use trans fats?

Trans fats are easy to use, inexpensive to produce and last a long time. Trans fats give foods a desirable taste and texture. Many restaurants and fast-food outlets use trans fats to deep-fry foods because oils with trans fats can be used many times in commercial fryers. Several countries (e.g., Denmark, Switzerland, and Canada) and jurisdictions (California, New York City, Baltimore, and Montgomery County, MD) have reduced or restricted the use of trans fats in food service establishments.

How do trans fats affect my health?

Trans fats raise your bad (LDL) cholesterol levels and lower your good (HDL) cholesterol levels. Eating trans fats increases your risk of developing heart disease and stroke. It’s also associated with a higher risk of developing type 2 diabetes.

Why did trans fats become so popular if they have such bad health effects?

Before 1990, very little was known about how trans fat can harm your health. In the 1990s, research began identifying the adverse health effects of transfats. Based on these findings, FDA instituted labeling regulations fortrans fat and consumption has decreased in the US in recent decades, however some individuals may consume high levels of trans fats based on their food choices.

Which foods contain trans fats?

Trans fats can be found in many foods – including fried foods like doughnuts, and baked goods including cakes, pie crusts, biscuits, frozen pizza, cookies, crackers, and stick margarines and other spreads. You can determine the amount of trans fats in a particular packaged food by looking at the Nutrition Facts panel. However, products can be listed as “0 grams of trans fats” if they contain 0 grams to less than 0.5 grams of trans fat per serving. You can also spot trans fats by reading ingredient lists and looking for the ingredients referred to as “partially hydrogenated oils.”

Are there naturally occurring trans fats?

Small amounts of trans fats occur naturally in some meat and dairy products, including beef, lamb and butterfat. There have not been sufficient studies to determine whether these naturally occurringtrans fats have the same bad effects on cholesterol levels as trans fats that have been industrially manufactured.

How much trans fat can I eat a day?

The American Heart Association recommends cutting back on foods containing partially hydrogenated vegetable oils to reduce trans fat in your diet and preparing lean meats and poultry without added saturated and trans fat.

How can I limit my daily oftrans fats?

Read the Nutrition Facts panel on foods you buy at the store and, when eating out, ask what kind of oil foods are cooked in. Replace the trans fats in your diet with monounsaturated or polyunsaturated fats.

Regulating Your Intake of Saturated and Trans Fats

The American Heart Association recommends that adults who would benefit from lowering LDL cholesterol reduce their intake of trans fat and limit their consumption of saturated fat to 5 to 6% of total calories.

Here are some ways to achieve that:

• Eat a dietary pattern that emphasizes fruits, vegetables, whole grains, low-fat dairy products, poultry, fish and nuts. Also limit red meat and sugary foods and beverages.
• Use naturally occurring, unhydrogenated vegetable oils such as canola, safflower, sunflower or olive oil most often.
• Look for processed foods made with unhydrogenated oil rather than partially hydrogenated or hydrogenated vegetable oils or saturated fat.
• Use soft margarine as a substitute for butter, and choose soft margarines (liquid or tub varieties) over harder stick forms. Look for “0 g trans fat” on the Nutrition Facts label and no hydrogenated oils in the ingredients list.
• Doughnuts, cookies, crackers, muffins, pies and cakes are examples of foods that may contain trans fat. Limit how frequently you eat them.
• Limit commercially fried foods and baked goods made with shortening or partially hydrogenated vegetable oils. Not only are these foods very high in fat, but that fat is also likely to be trans fat.
• Read the full American Heart Association Diet and Lifestyle Recommendations.