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Updated: May 5, 2026
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Characterization of Metabolic Status in Nonhuman Primates with the Intravenous Glucose Tolerance Test
Published on: November 13, 2016
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Plasma acetone metabolism in the fasting human
The Journal of Clinical Investigation
|April 1, 1979
Summary
Acetone metabolism in humans during starvation ketosis shows that while some is excreted, most is metabolized in vivo. This metabolic fate shifts with prolonged fasting, impacting glucose and lipid synthesis.
Area of Science:
- Human metabolism
- Ketosis
- Biochemistry
Background:
- Starvation ketosis leads to elevated acetone levels.
- Understanding acetone's metabolic fate is crucial for human physiology.
Purpose of the Study:
- To investigate acetone metabolism in lean and obese humans during starvation ketosis.
- To quantify acetone production, excretion, and in vivo utilization.
Main Methods:
- Measurement of acetone concentrations in plasma, urine, and breath.
- Determination of endogenous production, breath and urinary elimination, and in vivo metabolism rates.
- Use of [(14)C]acetone to trace metabolic pathways.
Main Results:
- A direct relationship exists between plasma acetone turnover and concentration.
- Acetone excretion via breath and urine accounts for only 2-30% of production.
- In vivo metabolism, primarily oxidation, accounts for the majority of acetone utilization, decreasing with prolonged fasting.
Conclusions:
- Acetone is primarily metabolized in vivo during starvation ketosis, with oxidation being a major pathway.
- The contribution of acetone oxidation to overall CO2 production is minimal.
- Acetone may serve as a precursor for glucose and lipid synthesis during prolonged fasting.
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