Citrulline is a naturally occurring non-protein amino acid found initially in watermelon (Citrullus vulgaris), hence its name. It has important physiological functions in the human body, especially in the urea cycle, which plays a key role.
Main sources:
1. Natural food source.
* Watermelon: Watermelon is the leading natural source of citrulline, containing about 0.1-0.2 grams of citrulline per 100 grams.
* Other melons, such as melon and balsam pear, also contain a certain amount of citrulline, but the content is relatively low.
* Cucumber: contains small amounts of citrulline.
* Pumpkin: Also a source of citrulline.
* Nuts and seeds, such as almonds and sunflower seeds, contain small amounts of citrulline.
2. Dietary supplement.
* Citrulline powder: pure citrulline powder that can be added to beverages or foods.
* Citrulline capsules or tablets: a convenient oral supplement.
3. In the urea cycle, carbamyl phosphate reacts with Ornithine to form citrulline, an essential metabolic process in the liver. Arginine metabolism: Arginine is produced as citrulline during Nitric Oxide synthesis.
Conclusion: citrulline can be obtained from natural foods and dietary supplements and synthesized in the body. Watermelon is the most abundant natural source, and some other melons, nuts, and seeds also contain small amounts of citrulline. For those needing additional support, a dietary supplement is a convenient and effective way. The human body’s urea cycle and arginine metabolism can also synthesize citrulline, ensuring its supply in the body.
Physiological function
1. Urea cycle:
* Citrulline is an intermediate in the urea cycle, an essential biological process in the liver that converts ammonia into urea for excretion from the body.
* in the urea cycle, citrulline is produced from Carbamoyl phosphate and Ornithine and then converted to Arginine.
2. Synthesis of Nitric Oxide (NO) :
* Citrulline can be converted to Arginine through a series of reactions, and Arginine is the precursor of NO synthesis.
* NO is a vital cell signal molecule in physiological processes such as vasodilatation, immune response, and nerve transmission.
Main benefits:
1. Improved performance
* Reduced fatigue: Citrulline can dilate blood vessels by increasing the production of Nitric Oxide (No), improving blood flow, increasing the supply of oxygen and nutrients, and reducing fatigue during exercise.
* Increased Endurance: studies have shown that citrulline supplementation increases Arginine and NO levels, muscle endurance, and performance.
* Promote muscle recovery: citrulline supplementation after exercise helps speed muscle recovery and reduce delayed onset muscle soreness (DOMS).
2. Increases cardiovascular health.
* Lowers blood pressure: citrulline helps blood vessels dilate by increasing NO production, which lowers blood pressure and improves circulation.
* Improve arterial function: No protective effects on arterial endothelial cells help maintain healthy arterial function and prevent arteriosclerosis.
3. Supporting the immune system.
* Enhances the immune response: citrulline and Arginine play an essential role in immune cells, helping to strengthen the immune system’s ability to respond and improve the body’s ability to fight infections and disease.
4. Improved cognitive function.
* Promotes cerebral blood flow: by increasing NO production, citrulline helps improve blood flow to the brain, thereby supporting cognitive function and brain health.
5. Supporting the role of a healthy liver in the urea cycle: Citrulline is an essential intermediate in the urea cycle that helps convert ammonia into urea, thereby contributing to liver detoxification and amino acid metabolism balance.
6. Enhanced sexual function improves erectile function: by increasing NO production, citrulline helps improve blood flow to the sexual organs, thereby improving erectile function in men.
7. Help manage the potential for blood sugar regulation: some studies suggest that citrulline may have a role in regulating blood sugar levels, helping to maintain blood sugar balance.
8. Antioxidant protection: citrulline has specific antioxidant properties that help neutralize free radicals and protect cells from oxidative damage.
Conclusion: citrulline, an essential non-protein amino acid, brings multiple health benefits by increasing Arginine and Nitric Oxide levels. Citrulline has been widely used to improve exercise performance, support cardiovascular health, and enhance immune and cognitive function. Citrulline supplementation in moderation can have a significant positive effect on overall health.
Potential side effects:
1. Stomach upset
* Abdominal distention and pain: some people may experience abdominal distention or pain after taking citrulline supplements. This may be due to the gastrointestinal response to citrulline. * Diarrhoea: high doses of citrulline may cause diarrhea, especially in sensitive populations.
2. Low blood pressure: because citrulline increases the production of Nitric Oxide (No), which dilates blood vessels, excessive use can cause low blood pressure, dizziness, fatigue, and other symptoms.
3. Vasodilation: Increased nitric Oxide can cause vasodilation, which can cause headaches in some people, especially those sensitive to No.
4. Allergic reactions to rash and pruritus: although rare, some people may develop allergic reactions to citrulline, such as rash, pruritus, or other skin problems.
5. Other potential problems.
* Drug interaction: Citrulline may interact with certain drugs, such as blood pressure drugs or vasodilators, leading to increased drug effects or side effects. Therefore, people with related health problems or who are taking medication should consult their doctor before using it.
* Effects on kidney health: although there is no clear evidence that citrulline hurts the kidney, it should be used cautiously in patients with kidney disease or dysfunction because of its role in the urea cycle. Consult a medical professional.
Citrulline, a dietary supplement, is generally safe in moderate doses with relatively few side effects. But people who overuse or are sensitive to it may experience side effects such as gastrointestinal discomfort, headaches, or changes in blood pressure. It is best to consult a medical professional before starting citrulline supplements, especially if you have health problems or are taking medication.
