HOW POLYUNSATURATED FATS AFFECT YOUR HEALTH

Polyunsaturated fats can help lower your LDL (bad) cholesterol. Cholesterol is a soft, waxy substance that can cause clogged or blocked arteries (blood vessels). Having low LDL cholesterol reduces your risk for heart disease.

Polyunsaturated fats include omega-3 and omega-6 fats. These are essential fatty acids that the body needs for brain function and cell growth. Our bodies do not make essential fatty acids, so you must get them from food.

Omega-3 fatty acids are good for your heart in several ways. They help:

• Reduce triglycerides, a type of fat in your blood
• Reduce the risk of developing an irregular heartbeat (arrhythmia)
• Slow the buildup of plaque, a substance comprising fat, cholesterol, and calcium, which can harden and clog your arteries
• Slightly lower your blood pressure

Omega-6 fatty acids may help:

• Control your blood sugar
• Reduce your risk for diabetes
• Lower your blood pressure

HOW MUCH SHOULD YOU EAT?

Your body needs some fat for energy and other functions. Polyunsaturated fats are a healthy choice. The 2020-2025 Dietary Guidelines for Americans recommends getting no more than 10% of your total daily calories from saturated fat (found in red meat, butter, cheese, and whole-fat dairy products). Keep total fat consumption to no more than 25% to 30% of your daily calories. This includes monounsaturated and polyunsaturated fats.

Eating healthier fats can lead to certain health benefits. But eating too much fat can lead to weight gain. All fats contain 9 calories per gram. This is more than twice the amount of calories found in carbohydrates and protein.

It is not enough to add foods high in unsaturated fats to a diet filled with unhealthy foods and fats. Instead, replace saturated fats with healthier fats. Overall, eliminating saturated fats is twice as effective in lowering blood cholesterol levels as increasing polyunsaturated fats.

READING NUTRITION LABELS

All packaged foods have nutrition labels on them that include fat content. Reading food labels can help you keep track of how much fat you eat a day.

• Check the total fat in one serving. Be sure to add up the number of servings you eat in one sitting.
• Look at the amount of saturated fat and trans fat in a serving -- the rest is healthy, unsaturated fat. Some labels will note the monounsaturated and polyunsaturated fat contents. Some will not.
• Make sure most of your daily fats are from monounsaturated and polyunsaturated sources.
• Many fast-food restaurants also provide nutrition information on their menus. If you do not see it posted, ask your server. You also may be able to find it on the restaurant's website.

MAKING HEALTHY FOOD CHOICES

Most foods have a combination of all types of fats. Some have higher amounts of healthy fats than others. Foods and oils with higher amounts of polyunsaturated fats include:

• Walnuts
• Sunflower seeds
• Flax seeds or flax oil
• Fish, such as salmon, mackerel, herring, albacore tuna, and trout
• Corn oil
• Soybean oil
• Safflower oil

To get the health benefits, you need to replace unhealthy fats with healthy fats. Here are some ideas:

• Eat walnuts instead of cookies for a snack. Be sure to keep your portion small, as nuts are high in calories.
• Replace some meats with fish. Try eating at least 2 meals with fish per week.
• Sprinkle ground flax seed on your meal.
• Add walnuts or sunflower seeds to salads.
• Cook with corn or safflower oil instead of butter and solid fats.

Polyunsaturated fatty acid; PUFA; Cholesterol - polyunsaturated fat; Atherosclerosis - polyunsaturated fat; Hardening of the arteries - polyunsaturated fat; Hyperlipidemia - polyunsaturated fat; Hypercholesterolemia - polyunsaturated fat; Coronary artery disease - polyunsaturated fat; Heart disease - polyunsaturated fat; Peripheral artery disease - polyunsaturated fat; PAD - polyunsaturated fat; Stroke - polyunsaturated fat; CAD - polyunsaturated fat; Heart healthy diet - polyunsaturated fat

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Grundy SM, Stone NJ, Bailey AL, et al. 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA Guideline on the management of blood cholesterol: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol. 2019;73(24):e285-e350. PMID: 30423393 pubmed.ncbi.nlm.nih.gov/30423393/.

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Mozaffarian D. Nutrition and cardiovascular and metabolic diseases. In: Libby P, Bonow RO, Mann DL, Tomaselli GF, Bhatt DL, Solomon SD, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 12th ed. Philadelphia, PA: Elsevier; 2022:chap 29.

US Department of Agriculture and US Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th ed. www.dietaryguidelines.gov/sites/default/files/2020-12/Dietary_Guidelines_for_Americans_2020-2025.pdf. Accessed June 11, 2024.

Updated by: Stefania Manetti, RDN, CDCES, RYT200, My Vita Sana LLC - Nourish and heal through food, San Jose, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.