ketosis

American  

[ki-toh-sis] / kɪˈtoʊ sɪs /

noun

Pathology.

1. the accumulation of excessive ketones in the body, as in diabetic acidosis.

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ketosis British  

/ kɪˈtəʊsɪs /

noun

1. Also called: acetonaemia.  pathol a high concentration of ketone bodies in the blood

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Etymology

Origin of ketosis

First recorded in 1915–20; ket- + -osis

Compare meaning

How does ketosis compare to similar and commonly confused words? Explore the most common comparisons:

• ketogenesis vs. ketosis

Explanation

When the body runs out of carbohydrates to burn for energy, it burns fat instead and goes through a process called ketosis. When someone is fasting, it's not uncommon for their body to enter a state of ketosis. The process has been studied by scientists and found to be useful in treating some kinds of diabetes and epilepsy. Sometimes people eliminate certain kinds of carbohydrates from their diet in order to put their body into ketosis, as a way of burning fat. Ketosis adds the medical -osis suffix, meaning "a state of disease," to ketone, the chemical name for the molecules produced by the liver during ketosis.

Example Sentences

By sharply reducing carbohydrates, the diet pushes the body into a state known as ketosis, in which fat is broken down into ketone bodies that serve as an alternative fuel for the brain.

From Science Daily • Jan. 27, 2026

The crux of a keto diet is ketosis, which is "a metabolic adaptation to allow the body to survive in a period of famine," per dieticians from the University of Chicago Medicine.

From Salon • Mar. 12, 2023

The popular keto diet is a low-carb, high-fat diet that puts your body into ketosis, the process in which your body burns fat, rather than carbohydrates, for fuel.

From Fox News • Jan. 5, 2022

“It’s not humanly possible to remain in ketosis in a healthy way until you are 100 years old,” Sperling says.

From Washington Post • Aug. 12, 2021

The odor is caused by ketones, chemicals produced when the body begins to burn fat instead of glucose for energy, a metabolic state known as ketosis.

From New York Times • Jul. 11, 2021