ketosis

noun

ke·​to·​sis kē-ˈtō-səs 

: an abnormal increase of ketone bodies in the body

ketotic

kē-ˈtä-tik 

adjective

Examples of ketosis in a Sentence

Recent Examples on the Web

With these hormonal changes plus a shift toward ketosis, even though the body is challenged with the same caloric intake and lack of exercise as before starting intermittent fasting, there will be a reduction in body fat. —Bryant Stamford, The Courier-Journal, 1 Aug. 2025

There’s another, less dangerous reason the liver might pump out ketones: ketosis. —Betsy Andrews, Saveur, 17 July 2025

During ketosis, the body breaks down fat into ketones and uses them for fuel. —Chelsea Rae Bourgeois, Rdn, Health, 24 Apr. 2025

The simplest definition of ketosis is a metabolic state in which the body begins using fat for its energy instead of carbohydrates. —Bestreviews, Chicago Tribune, 16 June 2025

Word History

Etymology

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."

First Known Use

1917, in the meaning defined above

Rhymes for ketosis

• cirrhosis
• fibrosis
• gliosis
• hypnosis
• ichthyosis
• kurtosis
• lordosis
• meiosis
• miosis
• mitosis
• mycosis
• narcosis

Medical Definition

ketosis

noun

ke·​to·​sis kē-ˈtō-səs 

plural ketoses -ˌsēz 

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

ketotic

-ˈtät-ik 

adjective