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Citrulline

L-Citrulline is an amino acid. It is turned into L-arginine in the kidneys after supplementation, which means L-citrulline supplementation is a more effective method of increasing L-arginine levels in the body than L-arginine supplementation.

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Summary of Citrulline

Primary Information, Benefits, Effects, and Important Facts

What is Citrulline?

L-Citrulline is one of the three dietary amino acids in the urea cycle, alongside L-arginine and L-Ornithine. Taking L-Citrulline increases plasma levels of ornithine and arginine and improves the ammonia recycling process and nitric oxide metabolism. Consequently, it is used in areas where nitric oxide is relevant, namely erectile dysfunction caused by high blood pressure, athletic performance, and cardiovascular health. There are very few foods that have notable amounts of citrulline.

What are Citrulline's benefits?

Limited research suggests that it results in reduced fatigue and improved endurance for both aerobic and anaerobic exercise. There isn't enough evidence to support the claim that L-citrulline supplementation improves power output during exercise. More research for erectile dysfunction and blood pressure is needed, but a small amount of research is supportive of a beneficial effect.

What are Citrulline's side effects and drawbacks?

It's not known to have notable side-effects, though more research is needed to confirm its long-term safety when taken in high doses. Unlike L-arginine and L-ornithine, very high doses don't seem to result in gastrointestinal upset.

Is arginine or citrulline better?

A small amount of research suggests that taking citrulline will lead to higher and more consistent arginine levels than taking arginine. Citrulline is very readily converted to arginine as needed, and it is also better absorbed than arginine, which not only makes it a better source of arginine for the body but can mean a lower rate of gastrointestinal upset than arginine when taken in high doses.

What is citrulline malate?

Citrulline bound to malate, an organic salt of malic acid, an intermediate in the citric acid cycle. It is the most researched form of citrulline, and there is speculation about an independent role of malate in producing performance benefits, but there's insufficient research to compare citrulline malate to L-citrulline directly. Citrulline malate can be taken in the dose used in studies, but it's important to keep in mind that 1.76 g of citrulline malate is needed to about 1 g of citrulline.

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Things To Know & Note

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Primary Function:

Also Known As

L-Citrulline, Stimol (Brand Name), Watermelon extract

How to Take Citrulline

Recommended dosage, active amounts, other details

To supplement L-citrulline for circulatory health or to alleviate erectile dysfunction, take 1,000 mg of citrulline, three times a day with meals, for a total daily dose of 3,000 mg. L-citrulline does not need to be taken with meals, however.

To supplement for circulatory health with a citrulline malate supplement, take 1.76 g of citrulline malate for every 1 gram of citrulline you would normally take.

To supplement L-citrulline to enhance sports performance, take 6,000 – 8,000 mg of citrulline malate about an hour before exercise.

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