Should You Take Citrulline Supplements? Exploring the Benefits and Risks

Citrulline, a naturally occurring amino acid, has gained popularity as a dietary supplement for its potential health and exercise performance benefits. While it can be produced by the body and found in certain foods like watermelon, citrulline supplements offer a way to increase its levels beyond typical amounts. In this article, we'll delve into what citrulline is, how it works, its potential health benefits, and the recommended dosages to help you decide if it's the right supplement for you.

Understanding Citrulline: Citrulline is an amino acid, originally discovered in watermelon, that the body can produce on its own. However, you can augment your citrulline levels by consuming foods rich in citrulline or by taking dietary supplements. This amino acid plays a vital role in the urea cycle, which helps eliminate harmful compounds from the body, particularly ammonia. Additionally, citrulline can widen blood vessels, potentially aiding in muscle building.

How Citrulline Works: One of the primary ways citrulline works is by increasing vasodilation, which refers to the widening of arteries and veins. This action is associated with lower blood pressure and enhanced blood flow. After consumption, citrulline can be converted into another amino acid called arginine, which further converts into nitric oxide—a molecule that relaxes smooth muscle cells in blood vessels, leading to vasodilation.

Moreover, citrulline can stimulate protein synthesis, contributing to muscle building, and reduce the liver's uptake of certain amino acids, preventing their breakdown. By stimulating protein synthesis and reducing amino acid breakdown, citrulline aids in maintaining or increasing muscle mass.

Citrulline in Foods: Citrulline can be found in various foods, with watermelon being a well-known source. Other foods containing citrulline include pumpkins, cucumbers, bitter melon, and gourds. However, the exact citrulline content of most foods has not been thoroughly analyzed.

Types of Citrulline Supplements: Citrulline supplements come in two main forms: L-citrulline and citrulline malate. L-citrulline is citrulline in its pure form, while citrulline malate is a combination of citrulline and malate, a compound important for energy production. Citrulline malate is more common in sports supplements, but it is not always clear which effects are due to citrulline and which are due to malate.

Health Benefits of Citrulline: Citrulline has been studied for its potential health benefits, particularly in relation to blood vessels, blood pressure, and exercise performance. It may help widen blood vessels, improving blood flow and potentially reducing blood pressure. However, its impact on blood vessel widening may be more significant with prolonged use rather than a single dose.

Studies have shown that citrulline supplements can reduce blood pressure, especially in individuals with high blood pressure or heart conditions. It may also increase growth hormone levels after exercise and potentially improve erectile function in men with erectile dysfunction.

Exercise Performance and Citrulline: Citrulline's ability to increase blood flow has prompted research into its effects on both endurance and strength-based exercise. Studies on endurance exercise using L-citrulline and strength-based research using citrulline malate have shown positive outcomes.

While a single dose of citrulline may not significantly improve endurance exercise performance, taking supplements for longer periods can improve oxygen usage in the exercising muscles and potentially enhance endurance. For weight training, citrulline malate has been found to improve performance, with participants able to perform more repetitions and experience reduced muscle soreness.

Recommended Dosages: Based on current research, a recommended daily dose is 3–6 grams of L-citrulline or approximately 8 grams of citrulline malate. Citrulline malate is preferred for weight training, while L-citrulline may be more effective for increasing oxygen content in muscles. Doses of at least 10 grams do not typically cause upset stomach, making citrulline well-tolerated.

Safety of Citrulline Supplements: Preliminary information suggests that citrulline is safe at higher doses. Even at the highest doses studied (15 grams of L-citrulline), no side effects were reported, and blood analysis showed no negative changes to normal body functions or blood pressure. However, doses greater than 10 grams are likely unnecessary, as they may not significantly increase arginine in the blood.

The Verdict: Citrulline supplements offer potential benefits for cardiovascular health, exercise performance, and muscle building. Its safety profile appears favorable, with no known side effects at recommended dosages. If you're looking to improve your exercise performance or promote heart health, citrulline supplements may be worth considering. As with any supplement, it's essential to consult with a healthcare professional before incorporating citrulline into your routine, especially if you have any pre-existing health conditions or take other medications.

In conclusion, citrulline is an amino acid that has shown promising effects on blood vessels, blood pressure, and exercise performance. While it can be obtained from certain foods, supplements offer a convenient way to increase citrulline levels. Consider adding citrulline supplements to your regimen if you are looking to enhance your exercise performance or promote heart health. Always remember to consult with a healthcare professional before starting any new supplement to ensure it aligns with your individual health needs and goals. With proper use and guidance, citrulline supplements could be a valuable addition to your health and fitness journey.