L-arginine is a conditionally essential amino acid that plays a role in building the proteins in our body. Although arginine is synthesized in the body, it is not made in sufficient quantities to meet the metabolic requirements during certain health conditions. In such cases, l-arginine supplements may help. It has been studied extensively as a precursor of nitric oxide (a compound that relaxes blood vessels in humans). An individual’s body naturally produces l-arginine though there are cases where it is supplemented. People who are under certain medications are prescribed this amino acid in the form of oral medication.
This nutritionally essential amino acid has many health benefits and has been used to treat several ailments. It may treat heart disease, reduce high blood pressure, ease inflammation in the digestive tract, aid diabetes treatment, heal wounds, and boost immune health.
Help Treat Heart Disease
In a study, long-term oral administration of l-arginine for 6 months improved the symptoms of non-obstructive coronary artery disease. L-arginine helps in the treatment of coronary abnormalities caused by high blood cholesterol levels. L-arginine enhances blood flow in coronary arteries. This may help in treating various cardiovascular conditions. L-arginine is the precursor of nitric oxide. Nitric oxide plays a role in various physiological effects in the cardiovascular system. The oral administration of l-arginine could improve symptoms of cardiovascular disease. Dietary supplementation of l-arginine, along with regular physical exercise, was also found to benefit patients with chronic heart failure.
Reduce High Blood Pressure
Oral administration of l-arginine could significantly lower both systolic and diastolic blood pressure levels. External l-arginine had also rapidly reduced systolic and diastolic blood pressure levels in both healthy humans and patients with hypertension. In one study, l-arginine supplemented at 4 grams per day could significantly lower blood pressure in women with gestational hypertension. The supplement also reduced the need for an anti-hypertensive therapy. L-arginine supplementation in pregnant women with chronic hypertension could reduce their blood pressure levels. The supplement could also offer protection in high-risk pregnancy.
Ease Inflammation Of The Digestive Tract In Premature Infants
L-arginine may ease the inflammation of the digestive tract in premature infants. In a study, dietary supplementation of l-arginine enhanced the intestinal growth and eased inflammation in weaning piglets. Similar outcomes could be expected in human babies too, though more research is warranted. In another study, plasma l-arginine concentrations were lower in premature infants diagnosed with necrotizing enterocolitis (NEC). NEC is a disease that destroys intestinal walls in premature infants. L-arginine supplementation was found to reduce the incidence of all stages of NEC.
Treat Gastrointestinal Tract Problems
Mice studies reveal that l-arginine can improve colonic motility. It also has the potential to alleviate GI discomfort. However, more long-term research is needed to understand this effect of l-arginine in humans.
Help Prevent Diabetes And Related Complications
L-arginine may help prevent diabetes and related complications. Diabetes is associated with reduced plasma levels of arginine. Evidence suggests that l-arginine supplementation may be an effective way to improve endothelial function in individuals with diabetes mellitus. L-arginine may also counteract cell damage and reduce the long-term complications of type 2 diabetes. It also improves insulin sensitivity. L-arginine supplementation was also found to reduce the risk of diabetes mellitus.
Boost Immune Health
L-arginine may boost immune health by stimulating lymphocytes (white blood cells). Intracellular l-arginine levels directly impact the metabolic fitness and survival capacity of T cells (a type of white blood cell) that are crucial for anti-tumor responses. L-arginine is an essential amino acid that is fundamental for the function of T lymphocytes (T-cells). Patients with cancer usually have an impaired T‐cell response that can decrease the potential therapeutic benefit of cancer vaccines and other forms of immunotherapy. L-arginine may regulate T-cell function in the case of chronic inflammatory diseases and cancer. L-arginine metabolism plays a major role in autoimmune and neoplastic (tumor-related) diseases. L-arginine supplementation inhibits the growth of breast cancer by enhancing innate and adaptive immune responses.
Help Treat Erectile Dysfunction
L-arginine may help treat sexual dysfunction. Arginine is required for normal spermatogenesis. Oral administration of 500 mg of arginine–HCl per day to infertile men for 6–8 weeks markedly increased their sperm counts. Oral administration of l-arginine in high doses lead to significant improvement in sexual function. Long-term oral administration of pharmacological doses of l-arginine was found to improve erectile responses in an aging rat.
May Improve Blood Flow
L-arginine infusion was found to promote regional cerebral blood flow in hypertensive rats (27). It also could improve vasodilation (dilation of blood vessels that reduces blood pressure) in hypercholesterolemic (high levels of cholesterol in blood) humans. L-arginine infusion in healthy subjects could inhibit platelet aggregation and blood viscosity and also promoted leg blood flow. L-arginine administration in rats could also improve post-traumatic cerebral blood flow.
Aid Weight Loss
L-arginine has been proven to stimulate fat metabolism. This may help in weight loss. The amino acid alters the balance of energy intake and expenditure in favor of fat loss. It also regulates brown adipose tissue and reduces the accumulation of white fat in the body. However, more long-term research is needed to understand this benefit of l-arginine in humans.
May Heal Wounds
Dietary l-arginine has been shown to improve collagen deposition and wound healing in both humans and animals. L-arginine may improve wound immune cell function by decreasing the inflammatory response at the wound site.
L-arginine administration during burn injuries was found to boost cardiac performance. It also could prevent bacterial translocation. L-arginine supplementation during the early stage of burns was found to help with the resuscitation of the burn shock. Oral dietary l-arginine supplementation of 100–400 mg/kg/day could accelerate the synthesis of reparative collagen in burned rats.
Improve Kidney Function In People With Congestive Heart Failure
Nitric oxide deficiency contributes to cardiovascular events and the progression of kidney damage. Low plasma levels of l-arginine is one of the major causes of nitric oxide deficiency. Supplementation of l-arginine was found to improve kidney function. Oral administration of l-arginine also had beneficial effects in renal function in patients with congestive heart failure. In another study, a moderate increase in l-arginine supplementation significantly lowered blood pressure. It also had improved renal function in healthy individuals.