L-arginine is an amino acid (building block of proteins) that is found naturally in food and can also be taken as a dietary supplement. L-arginine is known for its role in nitric oxide synthesis, which is thought to improve blood flow, helping bring nutrients and oxygen to muscle tissues. It is also used to help promote wound healing and increase blood flow to cold hands and feet in people with diabetes.
A high-quality, randomized clinical trial is needed to determine if L-arginine supplements can help increase muscle mass. However, it does seem to help enhance the body’s ability to perform exercise by increasing blood flow, which may increase strength and speed.
Arginine is an important building block of protein and helps the body produce other important substances such as ornithine, agmatine, creatine, glutamine, guanine, alanine, valine, and proline. In addition, it is involved in various metabolic processes, including regulation of blood sugar and blood pressure, immune function, muscle growth, fat metabolism, and cell division.
It is available as a dietary supplement under several different brand names, including L-arginine and RGene-10. Arginine is often combined with antioxidants and other nutritional supplements such as omega-3 fish oil, vitamin C, and folic acid, to promote heart health. Several studies have shown that arginine can improve insulin sensitivity in people with diabetes and lower blood sugar levels. It is also useful in reducing the effects of chronic inflammation and raising the activity of the immune system.
Other uses for arginine include treatment of chest pain caused by narrowing of blood vessels (angina), erectile dysfunction, and a serious disease in premature infants called necrotizing enterocolitis. However, evidence for these uses is limited. arginine is likely safe to take in short-term doses up to 9 grams per day, but it can cause gastrointestinal side effects and interact with some medications.
Talk to your doctor before taking arginine. If you have a history of heart disease, it is not recommended to take arginine because it might raise your risk for a heart attack. Similarly, it should not be used by people with herpes who are taking a medicine to treat the infection because it might trigger herpes outbreaks. If you have diabetes, high doses of arginine may interfere with blood glucose control. Arginine is generally safe to use in people with other medical conditions, but it’s important to discuss any new medication or supplements with your doctor.