- What Is
- What is L-citrulline?
- Where to Get
- Where can you get L-citrulline?
- How It Works
- How does L-citrulline work?
- Benefits and Uses
- L-citrulline benefits and uses
- Can You Take It Every Day?
- Can you take L-citrulline every day?
- Side Effects
- L-citrulline side effects
- Talk to Your Doctor
- L-citrulline and you
- Comments
- **COMMENTSTAGLIST**
- More
- **OTHERTAGLIST**
What is L-citrulline?
L-citrulline also improves nitrogen homeostasis through its crucial role in the urea cycle. L-citrulline has cardiovascular and gastrointestinal benefits.
As the use of supplements for exercise and overall health benefits increases, L-citrulline is one supplement that is rising in popularity. L-citrulline is an amino acid that naturally occurs in the body and is recognized for its numerous health benefits. It is consumed through various foods and can also be taken as a supplement.
This amino acid can potentially alleviate a variety of health issues, but how exactly can you use it? And how often should you take it?
L-citrulline is classified as an amino acid, a molecule that forms proteins. Amino acids also function as an energy source for the body. L-citrulline is a nonessential amino acid. This simply means our bodies will produce it even if we don’t directly consume it.
Specifically, L-citrulline assists with the urea cycle, when our bodies convert toxic ammonia into urea in urine. It has also gained attention from the medical field as a potential biomarker in the intestine for various conditions.
L-citrulline is also popular because it converts into nitric oxide and L-arginine, two substances that can expand arteries and assist with blood flow.
Where can you get L-citrulline?
You can add L-citrulline to your diet by consuming certain foods and supplements.
The food source highest in L-citrulline is watermelon. This includes red, yellow, and orange watermelon, both seeded and seedless. Many of the L-citrulline benefits listed in the sections below can be achieved through eating this nutrient-rich fruit.
Along with watermelon, L-citrulline is also present in the following fruits and vegetables:
- Cucumber
- Zucchini squash
- Calabaza squash
- Yellow squash
- Other melons
It is present in members of the plant family Cucurbitaceae, the gourd family — which includes watermelon.
You can also consume L-citrulline as a supplement. Numerous brands sell this supplement in different dosage amounts. L-citrulline supplements are taken to enhance exercise and bodybuilding, immune system function, and overall cardiovascular wellness.
How does L-citrulline work?
L-citrulline’s benefits stem from its ability to become nitric oxide and L-arginine.
Nitric oxide serves a role in many bodily processes by dilating blood vessels and increasing blood flow. It works within the body’s cardiovascular system, nervous system, lungs, intestines, kidneys, and immune system.
L-arginine is necessary for blood pressure control and immune system regulation. Through eating watermelon, one of the highest sources of L-citrulline, some studies demonstrated that the body successfully converts L-citrulline into L-arginine.
L-citrulline benefits and uses
By converting into nitric oxide and L-arginine, L-citrulline’s benefits are numerous and affect a variety of the body’s vital functions.
Cardiovascular benefits
Since L-citrulline enhances blood flow and blood vessel function, consuming it can decrease and regulate blood pressure. In one study, young men who took 6 grams of L-citrulline for 4 weeks experienced a decrease in systolic blood pressure. More research has confirmed L-citrulline’s benefits on systolic blood pressure in participants of a wide age range.
Another way that L-citrulline benefits the heart is through reducing endothelial dysfunction — a coronary artery disease causing the heart’s blood vessels to constrict. L-citrulline alleviates endothelial dysfunction by converting into nitric oxide, a necessary component in artery function. These benefits will strengthen the heart as the body ages.
Through relaxing blood vessels, L-citrulline can assist with the treatment of various diseases by boosting the body's immune system.
Taking L-citrulline can also improve exercise. One study found that L-citrulline’s effect on blood pressure benefited exercise performance in young adults. Once again, this was made possible through the amino acid’s conversion to L-arginine and nitric oxide.
L-citrulline’s role in increasing blood flow can also assist with bodybuilding by helping blood reach muscles more effectively.
L-citrulline can be used as an alternative treatment for erectile dysfunction to increase genital blood flow in men. One study resulted in fewer erectile dysfunction symptoms for patients after they took 1.5 grams of L-citrulline per day for 1 month.
As a result of the benefits mentioned above, L-citrulline is used for conditions such as:
- Short bowel syndrome
- Sickle cell anemia
- Erectile dysfunction
- Cancer chemotherapy
- Urea cycle issues
- Alzheimer’s disease
Biomarkers and the gastrointestinal system
L-citrulline also improves nitrogen homeostasis — or balance — through its crucial role in the urea cycle. Urea is the biggest source of nitrogen in urine, so its effective creation regulates the body's nitrogen balance.
L-citrulline levels are also now used as biomarkers for certain diseases. One study found that low levels of citrulline signaled small bowel disease, intestinal failure, and bowel inflammation among 500 patients. Medical professionals have become increasingly interested in the benefits of L-citrulline because of its role as a biomarker for these intestinal issues as well as other conditions.
Can you take L-citrulline every day?
Most health professionals agree that it's safe to take L-citrulline every day in recommended dosage amounts.
Based on current research, a balanced dose would be 3 to 6 grams of L-citrulline per day. Studies have demonstrated that the minimum effective dose is 3 grams of L-citrulline per day, while the maximum effective dose is 10 grams.
Exceeding 10 grams of L-citrulline in one dose could prove dangerous, as this can cause arginine oversaturation. This oversaturation can result in symptoms like:
- Increased asthma or allergy issues
- Nausea
- Bloating
- Headaches
- Lung inflammation
It’s best to consult your doctor before beginning L-citrulline supplements. Your primary physician can ensure that you know the best dosage for your desired results, whether they be for exercise or general wellness. They will also make sure that the supplement will not negatively interact with any other pre-existing health conditions or current medications.
L-citrulline side effects
If your doctor approves L-citrulline for you, you will most likely not experience any side effects. This is especially true if you stick to the recommended dosage and don't have certain underlying health conditions.
Many studies have demonstrated that there aren’t any L-citrulline side effects if you are healthy and following recommended dose amounts. L-citrulline supplements can actually be safer than prescription medications, such as those taken to combat erectile dysfunction.
Those at risk for side effects are:
- People who exceed the recommended L-citrulline dose
- People who have pre-existing health conditions that can be exacerbated by L-citrulline
You should avoid consuming L-citrulline if you have low blood pressure, kidney issues, or a condition that requires medicine to expand blood vessels. L-citrulline can negatively impact these pre-existing problems due to its effect on the cardiovascular system.
Exceeding the recommended L-citrulline dose can cause side effects to the digestive system, cardiovascular system, and renal system — specifically, the kidneys.
In one study, participants who continually took a large L-citrulline dose (over 10 grams) were at risk of developing gastrointestinal problems.This was due to a toxic oversaturation of nitric oxide in the small intestine.
L-citrulline doses exceeding the recommended amount can also detrimentally affect the kidneys. This supplement can overload the kidneys' creatine production, which can lead to kidney dysfunction.
Taking an L-citrulline dose that is too large can result in low blood pressure. If blood vessels become too dilated, then a person’s blood pressure can reach dangerously low levels, especially if that person regularly experiences low blood pressure.
As with any supplement, following your doctor’s recommendations about the most appropriate dose amount for you will guard against potential L-citrulline side effects.
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L-citrulline and you
Overall, L-citrulline is a safe, effective amino acid that can be absorbed by eating foods like watermelon or taking a supplement. It can result in many health benefits, especially for blood vessels and overall blood flow.
Be sure to speak with your doctor before beginning an L-citrulline supplement. These steps will help you know if L-citrulline is right for you and ensure that you’re taking the correct dosage.
Medically Reviewed on 9/20/2022
References
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