ke·​to·​sis | \ kē-ˈtō-səs How to pronounce ketosis (audio) \

Definition of ketosis

: an abnormal increase of ketone bodies in the body

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Other Words from ketosis

ketotic \ kē-​ˈtä-​tik How to pronounce ketosis (audio) \ adjective

Examples of ketosis in a Sentence

Recent Examples on the Web Unlike other low-carbohydrate diets — like the Atkins diet, which exclusively focus on cutting carbs — the keto diet emphasizes the body entering a state of ketosis. Stefanie Gordon, Woman's Day, "How to Start the Keto Diet, Because It's Not As Simple As Cutting Carbs," 11 Dec. 2020 During ketosis, the body becomes better at turning fat into energy. Jean Chen Smith, The Enquirer, "Keto? Fasting? Vegan? How all those fad diets stack up," 4 Nov. 2020 By eliminating or reducing carbs, this allows your body to go into ketosis. Jean Chen Smith, The Enquirer, "Keto? Fasting? Vegan? How all those fad diets stack up," 4 Nov. 2020 In another episode in 2018, a brand known as the Honest Keto Diet tried seeking investment for a supplement that supposedly helped Keto dieters maintain ketosis without strictly observing required sugar limitations that the diet is famous for. Zee Krstic, Good Housekeeping, "There’s a Major 'Shark Tank' Keto Pill Scam You Need to Know About," 16 Oct. 2020 The diet's main principle is maintaining ketosis, a metabolic state that pushes your body to burn fat for daily fuel rather than glucose sourced from carbohydrates. Zee Krstic, Good Housekeeping, "What You Can (and Can’t) Eat on a Keto Diet," 23 June 2020 Once in ketosis, the body has to burn fat (rather than sugar) for energy. Corey J. Maloney,, "A Type 2 Diabetes Diagnosis Prompted This Woman to Try the Keto Diet to Get the Disease Under Control," 30 June 2020 Eating a lot of protein and few carbs forces your body into ketosis, when your system begins to burn fat cells for energy. Sandee Lamotte, CNN, "Bad breath behind that coronavirus mask? 10 reasons -- and remedies -- for your halitosis," 5 May 2020 For those of you who don't know, manipulating your body into ketosis requires you to vastly restrict almost all sources of lean protein and almost all carbohydrates (fruits, veggies, and legumes included). Zee Krstic, Good Housekeeping, "The Best (And Worst!) Diets of 2020, According to a Registered Dietitian," 2 Mar. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ketosis.' 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 ketosis

1917, in the meaning defined above

History and Etymology for ketosis

ket(one) + -osis (after acidosis)

Note: The word ketosis was apparently introduced, somewhat hesitantly, by the American physician Frederick Madison Allen (1879-1964) in "The Role of Fat in Diabetes," American Journal of the Medical Sciences, series 2, vol. 153, no. 3 (March, 1917), p. 335: "The second basis of definition [of acidosis] is that of need and distinctiveness. Diminished alkalinity, increased hydrogen ion concentration, lowering of carbon dioxide, decrease of buffer salts, and (for the symptoms of these changes) acid intoxication—all these terms have definite meanings, and to appropriate the name acidosis for any one of them is merely to create a useless synonym. No other name but acidosis exists for the metabolic process which it denotes. Ketonuria and ketonemia have their accurate place but do not cover the ground. Possibly the word ketosis might be suggested and used for special purposes, but the change of established usage would be difficult and seems unnecessary."

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Time Traveler for ketosis

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The first known use of ketosis was in 1917

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Last Updated

7 Jan 2021

Cite this Entry

“Ketosis.” Dictionary, Merriam-Webster, Accessed 1 Mar. 2021.

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More Definitions for ketosis


ke·​to·​sis | \ kē-ˈtō-səs How to pronounce ketosis (audio) \
plural ketoses\ -​ˌsēz How to pronounce ketosis (audio) \

Medical Definition of ketosis

1 : an abnormal increase of ketone bodies in the body in conditions of reduced or disturbed carbohydrate metabolism (as in uncontrolled diabetes mellitus) — compare acidosis, alkalosis
2 : a nutritional disease of cattle and sometimes sheep, goats, or swine that is marked by reduction of blood sugar and the presence of ketone bodies in the blood, tissues, milk, and urine and is associated with digestive and nervous disturbances

Other Words from ketosis

ketotic \ -​ˈtät-​ik How to pronounce ketosis (audio) \ adjective

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