L-citrulline is an amino acid that may play an important role in testosterone production and sexual health in men. Here's an overview of the current research on L-citrulline and testosterone:
- Multiple studies have shown that supplementing with L-citrulline can significantly increase plasma L-arginine levels more effectively than supplementing with L-arginine itself. L-arginine is a precursor for nitric oxide production, which supports healthy blood flow.
- In one placebo-controlled study, L-citrulline supplementation (3 grams per day) for 2 weeks increased plasma L-arginine levels by 28% and nitric oxide production by 33%. This led to a significant improvement in mild erectile dysfunction in men.
- By increasing nitric oxide and improving blood flow, L-citrulline has been shown to enhance physical performance - increasing endurance, muscle protein synthesis, and growth hormone levels during exercise.
- Only a few studies have directly measured the effects of L-citrulline on testosterone levels specifically. However, many experts believe that the nitric oxide-enhancing and performance-improving effects of L-citrulline should also lead to increased testosterone production.
- One study found that taking L-citrulline one hour before resistance training led to higher levels of growth hormone and testosterone in the bloodstream following exercise.
- Research also shows many similarities between erectile dysfunction (ED) and low testosterone. Enhancing blood flow through increased nitric oxide levels may help alleviate symptoms of both low testosterone and ED.
Overall the research is promising when it comes to L-citrulline and testosterone. By enhancing nitric oxide production, L-citrulline supplementation appears to:
- Increase blood flow and nutrient delivery to tissues
- Improve physical performance and recovery
- Optimize growth hormone response
- Support erectile function
All of these effects should aid testosterone production and testosterone function throughout the body.
The physicians at Renewal Hormone Center can help determine if L-citrulline supplementation makes sense for optimizing your testosterone levels as part of a customized treatment plan. Reach out today to learn more.
Some key points on dosing and safety:
- The most common supplemental L-citrulline dose in studies ranges from 3-6 grams per day, often split into multiple doses throughout the day
- L-citrulline is considered very safe, with few side effects. Minor digestive upset is occasionally reported.
- No upper limit has been set for safe L-citrulline intake, but most studies use doses of 6 grams per day or less
- L-citrulline can amplify the blood pressure-lowering effects of medications for hypertension
- It's best to consult with your doctor before beginning supplementation if you have liver or kidney issues
The bottom line is that L-citrulline shows significant potential to become part of an evidence-based regimen to increase nitric oxide, blood flow, athletic performance, sexual health, and testosterone function. But more quality human trials are still needed to conclusively demonstrate effects on testosterone.
Some key future research that would help clarify the testosterone and L-citrulline relationship includes:
- Placebo-controlled, double-blind RCTs directly measuring changes in total and free testosterone levels in men following L-citrulline supplementation
- Studies on athletes/weightlifters to determine impacts on testosterone during intensive training periods
- Investigating underlying mechanisms - LH, FSH, growth hormone, estradiol changes
- Exploring dosage amount and timing for optimizing testosterone
- Longer-term studies tracking changes beyond 2 weeks
As the research continues to emerge,
L-citrulline remains a safe and promising option for supporting various aspects of men's health, including testosterone production.