Nutrient Database

L-Citrulline

amino acid

Approved

General information about nutrients. No diagnosis, no medical advice. If you take medication, are pregnant or have a medical condition, talk to your doctor before taking supplements.

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Overview

Amino acid converted to L-arginine in the kidneys, a precursor to nitric oxide.

Interactions

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Citrulline sustains Arginine/NO

Citrulline bypasses liver arginase (which breaks down oral arginine) and is converted to arginine in the kidneys, providing a sustained arginine supply for NO synthase.

Research status

More bioavailable NO precursor than arginine.

Top 5 food sources

Watermeloncucumberspumpkinsquashcantaloupe
Expert consensus: Moderate

More effective than L-arginine for raising arginine levels. Well-tolerated at 3–6g daily.