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

Many patients consider the keto diet, which emphasizes high fat and very low carbohydrate intake to trigger a metabolic state called ketosis, where the body burns fat instead of carbs for energy.

From Science Daily • Oct. 19, 2025

"These feelings have often been attributed to ketosis," he wrote, "the production of ketone bodies which can replace glucose as an energy source for the brain."

From Salon • Mar. 13, 2022

“The question is: How do you get there?” asks Freeman about ketosis, the metabolic state your body is in when it burns fat instead of carbs.

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

"I was absolutely wrong. The moment I got into full ketosis my milk increased."

From Fox News • Jan. 31, 2019