trans fat

noun

variants or trans-fat

ˈtran(t)s-ˈfat 

ˈtranz-

plural trans fats or trans-fats

: an unsaturated fat that contains a trans-fatty acid molecule which has a trans arrangement of double bonds in its hydrocarbon chain and that either occurs naturally in the meat and milk of ruminant animals (such as cows and sheep) or is manufactured by hydrogenating vegetable oil to create a fat (such as margarine or shortening) that is solid at room temperature

The trans fats to watch for are the ones artificially produced and placed in prepackaged foods or commercially prepared deep-fried foods. These trans fats are introduced during cooking or during the manufacturing process to help extend a product's shelf life. They also help some foods taste more satisfying.

—Jennifer Moll

… if you are not minding your intake of another harmful fat called trans-fat, you might still be increasing your risk of heart disease. Indeed, whereas saturated fat raises the body's level of bad "LDL" cholesterol, trans-fat packs a double whammy by also reducing the good "HDL" cholesterol that protects against heart disease …

—Anne Tergesen

compare saturated fat

Examples of trans fat in a Sentence

Recent Examples on the Web

While more studies are needed to confirm the effects of saturated and trans fats on prostate health, reducing your intake can benefit your heart and overall health. —Brittany Poulson, People.com, 8 July 2025

Saturated fats are found in dairy, red meat, and chicken skin, while most trans fats come from processed and packaged foods. —Yasmine S. Ali, Verywell Health, 25 June 2025

Healthy Fats Certain fats, including saturated and trans fats, can raise the risk of heart disease. —Carrie Madormo, Rn, Mph, Verywell Health, 2 May 2025

The first items in a list of CDC recommendations for preventing heart disease are all about food: Choose healthy meals and snacks high in fiber and limit saturated and trans fats, salt, and sugar. —Marianne Krasny, Forbes.com, 23 May 2025

Word History

First Known Use

1974, in the meaning defined above

Rhymes for trans fat

• begat
• bobcat
• chitchat
• doormat
• ducat
• eclat
• format
• hazmat
• muskrat
• nonfat
• polecat
• thereat

Medical Definition

trans fat

noun

variants or trans-fat

: an unsaturated fat that contains a trans-fatty acid molecule which has a trans arrangement of double bonds in its hydrocarbon chain and that either occurs naturally in the meat and milk of ruminant animals (such as cows or sheep) or is manufactured by hydrogenating vegetable oil to create a fat (such as margarine or shortening) that is solid at room temperature

Consumption of red meat and trans fats is associated with an increased risk of laparoscopically confirmed endometriosis …

—Linda C. Guidice, The New England Journal of Medicine

Trans fat is created when manufacturers partially hydrogenate liquid oils to make them more solid, more stable, and less greasy-tasting.

—Nutrition Action Health Letter

compare saturated fat