unsaturated fat

noun

plural unsaturated fats

: a fat (see fat entry 3 sense 2b) that contains a fatty acid (see fatty acid sense 2) molecule which has one or more double bonds in its hydrocarbon chain, that is liquid at room temperature, and that is found in many plant sources (such as nuts, seeds, and vegetable oils) and some fish

Research connects consuming moderate amounts of unsaturated fats with a slew of health benefits, most notably, lower risk of premature death. Unsaturated fats can help boost good cholesterol and lower bad cholesterol in your blood, which can lower your risk of heart disease or stroke …

—Cleveland Clinic

I found that brownies that contained mostly saturated fat (and thus lots of rigid carbon chains) baked up quite tender and not at all chewy, while brownies made with mostly unsaturated fat (and more flexible carbon chains) were the chewier ones.

—Andrea Geary

see also monounsaturated fat, polyunsaturated fat compare saturated fat, trans fat

Examples of unsaturated fat in a Sentence

Recent Examples on the Web

Healthy Oils Provide healthy unsaturated fats Plant oils like olive oil, sunflower oil, sesame oil, avocado oil, and peanut oil are considered healthy fats. —Lana Barhum, Verywell Health, 12 June 2026

The unsaturated fats give them an irregular shape on a molecular level. —Rosemary Trout, The Conversation, 10 June 2026

In addition to protein, pine nuts provide healthy unsaturated fats, magnesium, iron, and vitamin E. —Lindsey Desoto, Health, 3 June 2026

The key is choosing unsaturated fats over the fried and greasy options that tend to trigger side effects. —Samantha Agate, Kansas City Star, 28 May 2026

Almonds: Through a combination of healthy unsaturated fats, fiber and antioxidant-rich vitamin E, almonds can help lower LDL. —Gavin Escott, USA Today, 15 May 2026

Word History

First Known Use

1899, in the meaning defined above

Rhymes for unsaturated fat

• acrobat
• autocrat
• automat
• bundesrat
• bureaucrat
• butterfat
• caveat
• chemostat
• copycat
• cryostat
• democrat
• diplomat

Medical Definition

unsaturated fat

noun

: a fat (see fat entry 2 sense 2b) that contains a fatty acid (see fatty acid sense 2) molecule which has one or more double bonds in its hydrocarbon chain, that is liquid at room temperature, and that is found in many plant sources (such as nuts, seeds, and vegetable oils) and some fish

Foods from animal sources such as meat, milk, and eggs contain more saturated than unsaturated fats. Conversely, foods from vegetable sources such as the oils contain more unsaturated fat.

—Sue Rodwell Williams, Nutrition and Diet Therapy

"The data suggest that any oil that's high in unsaturated fats—whether it's polyunsaturated or monounsaturated—is associated with a decreased risk of cardiovascular disease," says Alice Lichtenstein of the U.S. Department of Agriculture …

—Bonnie Liebman, Nutrition Action Health Letter

see also monounsaturated fat, polyunsaturated fat compare saturated fat, trans fat