Learn all about L-Arginine
What is L-Arginine?
Improve blood flow & workout performance with L-arginine. This helps your body make nitric oxide, which supports heart health & muscle pump. Feel stronger!
Benefits of L-Arginine
"L-arginine connects sports nutrition and blood vessel health. Helping make nitric oxide makes it interesting for performance, but the best results are seen in specific situations, like high-power activities or in people with less-than-ideal blood vessel function, rather than all healthy young athletes. How well it works varies a lot based on a person's starting arginine levels, fitness, and how their body handles nitric oxide. For heart health uses, higher doses than found in typical pre-workout drinks are usually needed."
- Dr. Stuart Phillips, Professor of Kinesiology and Director of the Physical Activity Centre of Excellence at McMaster University (source)
How to use L-Arginine
Dosage
Usually 3-6 grams daily, split into 2-3 doses. For specific health issues, doses might be 6-18 grams daily, but only under medical advice.
Timing
Best taken on an empty stomach, 30-60 minutes before exercise if using for performance. Taking it at bedtime might help those using it for heart health.
Notes
Powder mixes well with water or juice. Slow-release capsules might cause fewer stomach issues. L-citrulline (2-3g daily) is sometimes used instead, as it converts to L-arginine in the body and might be absorbed better.
Who should take L-Arginine?
- Athletes wanting better performance, especially for power or high-intensity workouts
- People with mild to moderate heart concerns seeking extra support
- Men with mild to moderate erection problems who can't or prefer not to use standard treatments
- Those recovering from surgery, injury, or with slow wound healing (with medical guidance)
How does L-Arginine work?
L-arginine mainly works by helping the body make nitric oxide (NO), a chemical messenger that relaxes blood vessel muscles. This relaxation (vasodilation) widens blood vessels, increasing blood flow and delivering more oxygen and nutrients to tissues. L-arginine also triggers the release of growth hormone, insulin, and other substances involved in tissue repair. It helps remove ammonia waste from the body through the urea cycle. It's used to build proteins and is especially important for making creatine, which helps power muscles during high-energy activities. L-arginine also plays a role in the immune system by affecting certain immune cells.
Frequently asked questions
Natural sources of L-Arginine
L-arginine is found in many foods, especially animal proteins like red meat (venison, bison), poultry (turkey, chicken), and dairy (milk, yogurt, cheese). Plant sources include pumpkin seeds (very high), walnuts, almonds, other nuts, soybeans, chickpeas, and lentils. Whole grains also have some. Most diets provide 3-6 grams daily, which might not be enough for the specific effects targeted by supplements.
Potential side effects & risks
Warnings
Avoid or use carefully if you have herpes, as it might trigger outbreaks. Not recommended after a heart attack without medical advice. People with kidney or liver problems should talk to a doctor first. Stop taking it 2 weeks before surgery.
Side effects
Often causes stomach upset, bloating, and diarrhoea at higher doses. Can cause temporary headaches due to widened blood vessels. May cause low blood pressure and dizziness, especially if taken with other substances that widen blood vessels.
Interactions
May increase the effects of medicines for high blood pressure, erection problems (like sildenafil/Viagra), or blood thinners. May make lysine supplements less effective. Should NOT be taken with certain erection medicines (PDE5 inhibitors) due to risk of dangerously low blood pressure.