in·​su·​lin | \ ˈin(t)-s(ə-)lən How to pronounce insulin (audio) \

Definition of insulin

: a protein pancreatic hormone secreted by the beta cells of the islets of Langerhans that is essential especially for the metabolism of carbohydrates and the regulation of glucose levels in the blood and that when insufficiently produced results in diabetes mellitus

Examples of insulin in a Sentence

Recent Examples on the Web

Several studies have shown that a higher-fat diet can reduce cravings and levels of appetite-stimulating hormones ghrelin and insulin. Karla Walsh, Woman's Day, "The Ultimate Keto Diet Foods List of What You Can (and Can't) Eat," 28 Dec. 2018 What does occur, however, during times of extended fasting, is that blood sugar and insulin levels drastically decrease, Caroline Apovian, M.D., director of the Center for Nutrition and Weight Management at Boston Medical Center, tells SELF. SELF, "What You Need to Know Before Trying Intermittent Fasting," 7 Nov. 2018 But within a day or two of returning to their normal activities, their metabolisms usually stabilized and blood-sugar and insulin levels dropped. Gretchen Reynolds, The Seattle Times, "Planning a break from exercise? Think twice," 8 Aug. 2018 Would anyone judge someone with diabetes for taking insulin? Danielle Tcholakian, The Cut, "What It’s Like to Know You’ll Be on Antidepressants for Life," 12 Apr. 2018 Research also has shown that oats may lower blood pressure, increase insulin sensitivity and boost immunity. Ashleigh Spitza, Milwaukee Journal Sentinel, "Oats get your day off to a nutritious, filling start," 9 Jan. 2018 This is supposed to drive down insulin levels, ratchet up calorie burn, and help fat melt away. Julia Belluz, Vox, "Does cutting carbs really help keep weight off? The big new diet study, explained.," 17 Nov. 2018 The standard approach for people with Type 1 diabetes is to match carb intake with insulin. New York Times, "How a Low-Carb Diet Might Aid People With Type 1 Diabetes," 7 May 2018 Iverson, of Joliet, said that along with insulin, Bell requires a regular injection to treat her rheumatoid arthritis. Mike Nolan, Daily Southtown, "Family seeks help locating missing Richton Park woman," 23 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'insulin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of insulin

1914, in the meaning defined above

History and Etymology for insulin

New Latin insula islet (of Langerhans), from Latin, island

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Statistics for insulin

Last Updated

14 Mar 2019

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Time Traveler for insulin

The first known use of insulin was in 1914

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English Language Learners Definition of insulin

medical : a substance that your body makes and uses to turn sugar into energy


in·​su·​lin | \ ˈin-sə-lən How to pronounce insulin (audio) \

Kids Definition of insulin

: a hormone made by the pancreas that helps the cells in the body take up glucose from the blood and that is used to treat diabetes


in·​su·​lin | \ ˈin(t)-s(ə-)lən How to pronounce insulin (audio) \

Medical Definition of insulin

: a protein hormone that is synthesized in the pancreas from proinsulin and secreted by the beta cells of the islets of Langerhans, that is essential for the metabolism of carbohydrates, lipids, and proteins, that regulates blood sugar levels by facilitating the uptake of glucose into tissues, by promoting its conversion into glycogen, fatty acids, and triglycerides, and by reducing the release of glucose from the liver, and that when produced in insufficient quantities results in diabetes mellitus — see iletin

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More from Merriam-Webster on insulin

Spanish Central: Translation of insulin

Nglish: Translation of insulin for Spanish Speakers

Britannica English: Translation of insulin for Arabic Speakers Encyclopedia article about insulin

Comments on insulin

What made you want to look up insulin? Please tell us where you read or heard it (including the quote, if possible).


to boil down or concentrate

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