L-citrulline is a substance called a non-essential amino acid. Your kidneys change L-citrulline into another amino acid called L-arginine and a chemical called nitric oxide.
These compounds are important to your heart and blood vessel health. They may also boost your immune system.
As a supplement, some people use NAC to try to protect the liver. There's evidence it can help prevent liver damage caused by some cancer drugs.
Some animal studies have shown that NAC may help protect against some cancers. However, we don't know if it would have anti-cancer benefits in people.
There's mixed evidence about whether NAC helps with other conditions, like infertility, the flu, cystic fibrosis, liver disease, angina, HIV, and some eye conditions. More research is needed.
Optimal doses of NAC as a supplement have not been set for any condition. Quality and active ingredients in supplements may vary widely from maker to maker. This makes it very hard to set a standard dose.
There are standard doses for prescription uses of NAC. These depend on the condition that is being treated. Ask your doctor for advice.
Can you get NAC naturally from foods?
NAC is not in foods.
What are the risks?
Tell your doctor about any supplements you're taking, even if they're natural. That way, your doctor can check on any potential side effects or interactions with medications.
Side effects. NAC may cause:
Risks. Extremely high doses -- 60 to 100 times the normal amount -- have caused liver damage in animals. NAC may not be safe for people with asthma or with severe liver or kidney disease.