Overview

L-citrulline is a naturally occurring amino acid. It is found in some foods like watermelons and is also produced naturally by the body.

L-citrulline is used by mouth for heart failure and improving athletic performance. It is also used for sickle cell disease, erectile dysfunction, high blood pressure in the lungs, and many other conditions. But there is limited scientific research to support these other uses.

Classification

Is a Form of:

Amino acid

Primary Functions:

Heart failure

Also Known As:

Citrulline Malate, L-Citrulina, L-Citrulline AKG, L-Citrulline-Alpha Ketoglutaric Acid

How Does It Work?

L-citrulline is a naturally occurring amino acid found in food, such as watermelon. It is also made naturally in the body. The body changes L-citrulline into another amino acid called L-arginine and also to a chemical called nitric oxide. L-citrulline might help increase the supply of ingredients the body needs to make certain proteins. It might also help open up veins and arteries to improve blood flow and reduce blood pressure.

Uses

• Athletic performance. Taking L-citrulline by mouth might be effective for improving some types of exercise performance when taken for up to 7 days. L-citrulline may help some athletes work harder, lift weights longer, and go faster on an exercise bike. But it does not seem to help people run for longer distances. Also, taking L-citrulline for up to 8 weeks does not seem to increase muscle size or strength.
• Heart failure. L-citrulline can help people with heart failure who are already treated with standard medications. Taking L-citrulline by mouth seems to reduce blood pressure in the lungs in these patients. This helps the heart work better, allowing people with heart failure to walk farther.

Recommended Dosing

The following doses have been studied in scientific research:

ADULTS

BY MOUTH:

• For athletic performance: 2.4 grams or 5 grams daily for 7 days. A single dose of 8 grams just before exercise has also been used. L-citrulline maleate 2 grams daily for up to 8 weeks has also been used.
• For heart failure: 3 grams daily for 2-4 months.

L-Citrulline Supplements Frequently Asked Questions

Does L citrulline really work?

Prehypertension raises your risk for high blood pressure and heart disease. L-citrulline supplements may ease symptoms of mild-to-moderate erectile dysfunction (ED). Scientists say L-citrulline does not work as well as ED drugs such as Viagra. However, it appears to be a safe option.

What is L citrulline good for?

L-citrulline is used for Alzheimer's disease, dementia, fatigue, muscle weakness, sickle cell disease, erectile dysfunction, high blood pressure, and diabetes. It is used for heart disease, body building, increasing energy, and for improving athletic performance.

How much citrulline should you take a day?

How Much Should You Take? Based on current research, a recommended dose is 3–6 grams per day of L-citrulline or approximately 8 grams per day of citrulline malate. The dose varies depending on form because 1.75 grams of citrulline malate provides 1 gram of L-citrulline.

What are the side effects of citrulline?

L-citrulline is POSSIBLY SAFE when used orally and appropriately by adults. It is POSSIBLY SAFE when used orally and intravenously in children. Although side effects are rare, some people have reported stomach upset, heartburn, cough, changes in urination, and swelling when taking L-citrulline by mouth.

Can I take L citrulline every day?

How Much Should You Take? Based on current research, a recommended dose is 3–6 grams per day of L-citrulline or approximately 8 grams per day of citrulline malate. Blood pressure: For improving blood pressure, the daily dose of L-citrulline used in research is typically 3–6 grams per day.

Can you overdose on L citrulline?

Too Much of a Good Thing. Many athletes take L-Citrulline to improve their workout by increasing blood flow to muscle mass. However, taking too much of the nonessential amino acid can be dangerous. Because of that, doctors recommend not exceeding the recommended dose of any amino acid, including L-Citrulline.

Which is better l arginine or L citrulline?

Though research has found both arginine and citrulline to boost levels of nitric oxide in the body, most recent research—like this The Journal of Nutrition study—shows that citrulline actually delivers the most benefit. “Citrulline expands blood vessels to a greater extent than arginine,” says Spano.

Can I take arginine and citrulline together?

The combination of amino acids L-citrulline and L-arginine have been shown to have anti-atherosclerotic effects in previous research, but a new animal study suggests the combination may also rapidly increase nitric oxide (NO) bioavailability after short-term supplementation.

Is L citrulline bad for kidneys?

Another potential problem of taking too much L-Citrulline is the damaging effects it has on the body's kidneys. While the damage is not directly caused by L-Citrulline, the nonessential amino acid can increase creatinine levels to a dangerous point.

When should you take L citrulline?

When Should You Take Citrulline? Citrulline is most commonly added to pre-workout supplements. To see the best results, take a supplement that contains Citrulline about 30 minutes before your workout. Many people like to take these supplements on an empty stomach to promote better absorption.

Does L citrulline help with erectile dysfunction?

The body converts L-citrulline to L-arginine, another type of amino acid. L-arginine improves blood flow. ... The same effect on blood vessels helps improve symptoms of erectile dysfunction (ED). The L-citrulline to NO path increases blood flow to a man's genitals.

What happens if you take too much citrulline?

However, taking too much of the nonessential amino acid can be dangerous. This is because the medication is known to increase nitric oxide levels and dilate blood vessels that lower the body's blood pressure. Another potential problem of taking too much L-Citrulline is the damaging effects it has on the body's kidneys.

Does L citrulline increase testosterone?

The amino acids in L-Citrulline help in building lean muscle - boost strength and endurance by increasing protein synthesis. Testosterone is something the human body naturally understands, using it to push energy and give your body the burst of strength needed when lifting heavy weights.

How long does it take for citrulline to work?

It May Reduce Blood Pressure

What's more, in a small study examining 12 adults with normal blood pressure, researchers found that citrulline reduced blood pressure by 6–16% after 7 days ( 17 ).

What is L Arginine and L citrulline good for?

L-citrulline is an amino acid normally made by the body. The body converts L-citrulline to L-arginine, another type of amino acid. L-arginine improves blood flow. L-arginine has been shown to help people with heart disease or clogged arteries because of its vessel-widening abilities.

What is L Arginine and L citrulline used for?

The body changes L-citrulline into another amino acid called L-arginine and also to a chemical called nitric oxide. L-citrulline might help increase the supply of ingredients the body needs to make certain proteins. It might also help open up veins and arteries to improve blood flow and reduce blood pressure.

How much citrulline is in a cup of watermelon?

"That is a good question," Patil says. Unfortunately, "I don't have an answer for that." He does know that a typical 4-ounce serving of watermelon (about 10 watermelon balls) has about 150 milligrams of citrulline. But he can't say how much citrulline is needed to have Viagra-like effects.

Is L citrulline a blood thinner?

L-citrulline is a naturally occurring amino acid found in food, such as watermelon. L-citrulline might help increase the supply of ingredients the body needs to make certain proteins. It might also help open up veins and arteries to improve blood flow and reduce blood pressure.

Can citrulline cause insomnia?

What are the potential side effects? The evidence to support its use is thin on the ground, and it has been linked to side effects including insomnia, prostate issues, and lowering “good” cholesterol.

Clinical Studies

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• ^ Oral L-Citrulline Supplementation Improves Erection Hardness in Men With Mild Erectile Dysfunction.
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