Supplement

Arginine

Arginine is an amino acid the body uses to build proteins and to make nitric oxide, a molecule that relaxes blood vessels and helps blood flow. People mostly look at it for intermittent claudication, the leg pain that comes on with walking, and one small trial of 39 people found blood flow went up, though the evidence is limited. Results for related symptoms were mixed, so this is early, small-scale work that can't say much yet.

Sources: PMID 9809945

Updated 30 September 2026
How we grade
17 studies cited

Best evidence: Grade C
Conditions studied: 15
Outcomes: 80
Graded outcomes: 00106

Evidence by condition

Strong
Moderate
Limited
Very limited

15 conditions

General Cardiovascular Health

General Cardiovascular Health: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People
	Blood Flow Small Increase	Improves (the measure goes up)	Small effect	1 study	61 people
Studies that measured blood flow Restoring vascular nitric oxide formation by L-arginine improves the symptoms of intermittent claudication in patients with peripheral arterial occlusive diseaseJ Am Coll Cardiol · PMID 9809945
	Asymmetric dimethylarginine (aka ADMA) No effect		NoneNo effect		44 people

Muscle Size Strength

Muscle Size Strength: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Blood Flow Small Increase	Improves (the measure goes up)	Small effect	1 study	17 people
Studies that measured blood flow Restoring vascular nitric oxide formation by L-arginine improves the symptoms of intermittent claudication in patients with peripheral arterial occlusive diseaseJ Am Coll Cardiol · PMID 9809945

Intermittent Claudication

Blood Flow: improves
Nitric Oxide: improves
Intermittent Claudication Symptoms: changes; see studies

Intermittent Claudication: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People
	Blood Flow Small Increase	Improves (the measure goes up)	Small effect	1 study	39 people
Studies that measured blood flow Restoring vascular nitric oxide formation by L-arginine improves the symptoms of intermittent claudication in patients with peripheral arterial occlusive diseaseJ Am Coll Cardiol · PMID 9809945
	Nitric Oxide	Improves (the measure goes up)		4 studies	39 people
Studies that measured nitric oxide Beneficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulin-resistant type 2 diabetic patientsAm J Physiol Endocrinol Metab · PMID 16772327 No effect of short-term arginine supplementation on nitric oxide production, metabolism and performance in intermittent exercise in athletesJ Nutr Biochem · PMID 18708287 Effects of 7 days of arginine-alpha-ketoglutarate supplementation on blood flow, plasma L-arginine, nitric oxide metabolites, and asymmetric dimethyl arginine after resistance exerciseInt J Sport Nutr Exerc Metab · PMID 21813912 Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolismBr J Clin Pharmacol · PMID 17662090
	Intermittent Claudication Symptoms	Changes; see studies			39 people

Peripheral Arterial Occlusive Disease

Blood Flow: improves
Intermittent Claudication Symptoms
Nitric Oxide: improves

Peripheral Arterial Occlusive Disease: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People
	Blood Flow Small Increase	Improves (the measure goes up)	Small effect	1 study	39 people
Studies that measured blood flow Restoring vascular nitric oxide formation by L-arginine improves the symptoms of intermittent claudication in patients with peripheral arterial occlusive diseaseJ Am Coll Cardiol · PMID 9809945
	Intermittent Claudication Symptoms Mixed effect				39 people
	Nitric Oxide	Improves (the measure goes up)		4 studies	39 people
Studies that measured nitric oxide Beneficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulin-resistant type 2 diabetic patientsAm J Physiol Endocrinol Metab · PMID 16772327 No effect of short-term arginine supplementation on nitric oxide production, metabolism and performance in intermittent exercise in athletesJ Nutr Biochem · PMID 18708287 Effects of 7 days of arginine-alpha-ketoglutarate supplementation on blood flow, plasma L-arginine, nitric oxide metabolites, and asymmetric dimethyl arginine after resistance exerciseInt J Sport Nutr Exerc Metab · PMID 21813912 Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolismBr J Clin Pharmacol · PMID 17662090

Muscle Size & Strength

Blood Flow: improves
Heart Rate: changes; see studies
Vascular Function: improves

Muscle Size & Strength: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People
	Blood Flow Small Increase	Improves (the measure goes up)	Small effect	1 study	17 people
Studies that measured blood flow Restoring vascular nitric oxide formation by L-arginine improves the symptoms of intermittent claudication in patients with peripheral arterial occlusive diseaseJ Am Coll Cardiol · PMID 9809945
	Heart Rate	Changes; see studies		1 study	33 people
Studies that measured heart rate Acute L-arginine alpha ketoglutarate supplementation fails to improve muscular performance in resistance trained and untrained menJ Int Soc Sports Nutr · PMID 22510253
	Vascular Function	Improves (the measure goes up)		1 study	17 people
Studies that measured vascular function Hemodynamic and vascular response to resistance exercise with L-arginineMed Sci Sports Exerc · PMID 19276857
	Blood Pressure	Changes; see studies			17 people
	Power Output	Improves (the measure goes up)			16 people

General Athletic Performance

Anaerobic Capacity: improves
Nitric Oxide: improves
Growth Hormone: improves

General Athletic Performance: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People
	Anaerobic Capacity Small Improvement	Improves (the measure goes up)	Small effect		9 people
	Nitric Oxide	Improves (the measure goes up)		4 studies	9 people
Studies that measured nitric oxide Beneficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulin-resistant type 2 diabetic patientsAm J Physiol Endocrinol Metab · PMID 16772327 No effect of short-term arginine supplementation on nitric oxide production, metabolism and performance in intermittent exercise in athletesJ Nutr Biochem · PMID 18708287 Effects of 7 days of arginine-alpha-ketoglutarate supplementation on blood flow, plasma L-arginine, nitric oxide metabolites, and asymmetric dimethyl arginine after resistance exerciseInt J Sport Nutr Exerc Metab · PMID 21813912 Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolismBr J Clin Pharmacol · PMID 17662090
	Growth Hormone	Improves (the measure goes up)		3 studies	36 people
Studies that measured growth hormone Growth hormone responses to varying doses of oral arginineGrowth Horm IGF Res · PMID 15809017 Oral arginine does not stimulate basal or augment exercise-induced GH secretion in either young or old adultsJ Gerontol A Biol Sci Med Sci · PMID 10496544 Influence of chronic supplementation of arginine aspartate in endurance athletes on performance and substrate metabolism - a randomized, double-blind, placebo-controlled studyInt J Sports Med · PMID 15895316
	Blood Flow	Improves (the measure goes up)		1 study	17 people
Studies that measured blood flow Restoring vascular nitric oxide formation by L-arginine improves the symptoms of intermittent claudication in patients with peripheral arterial occlusive diseaseJ Am Coll Cardiol · PMID 9809945
	Heart Rate	Changes; see studies		1 study	33 people
Studies that measured heart rate Acute L-arginine alpha ketoglutarate supplementation fails to improve muscular performance in resistance trained and untrained menJ Int Soc Sports Nutr · PMID 22510253
	Vascular Function	Improves (the measure goes up)		1 study	17 people
	Blood Pressure	Changes; see studies			26 people
	Oxygen Cost of Exercise	Improves (the measure goes up)			9 people
	Power Output	Improves (the measure goes up)			16 people

Type 2 Diabetes

Adiponectin: improves
Nitric Oxide: improves
Plasma Arginine: improves

Type 2 Diabetes: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People
	Adiponectin Small Increase	Improves (the measure goes up)	Small effect		33 people
	Nitric Oxide	Improves (the measure goes up)		4 studies	33 people
Studies that measured nitric oxide Beneficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulin-resistant type 2 diabetic patientsAm J Physiol Endocrinol Metab · PMID 16772327 No effect of short-term arginine supplementation on nitric oxide production, metabolism and performance in intermittent exercise in athletesJ Nutr Biochem · PMID 18708287 Effects of 7 days of arginine-alpha-ketoglutarate supplementation on blood flow, plasma L-arginine, nitric oxide metabolites, and asymmetric dimethyl arginine after resistance exerciseInt J Sport Nutr Exerc Metab · PMID 21813912 Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolismBr J Clin Pharmacol · PMID 17662090
	Plasma Arginine	Improves (the measure goes up)		2 studies	144 people
Studies that measured plasma arginine L-arginine supplementation in peripheral arterial disease: no benefit and possible harmCirculation · PMID 17592080 L-arginine-induced vasodilation in healthy humans: pharmacokinetic-pharmacodynamic relationshipBr J Clin Pharmacol · PMID 9833603
	Blood Flow	Improves (the measure goes up)		1 study	144 people
Studies that measured blood flow Restoring vascular nitric oxide formation by L-arginine improves the symptoms of intermittent claudication in patients with peripheral arterial occlusive diseaseJ Am Coll Cardiol · PMID 9809945
	Blood glucose	Changes; see studies		1 study	144 people
Studies that measured blood glucose Effect of a long-term oral l-arginine supplementation on glucose metabolism: a randomized, double-blind, placebo-controlled trialDiabetes Obes Metab · PMID 22553931
	Insulin	Changes; see studies		1 study	144 people
	Vascular Function	Improves (the measure goes up)		1 study	33 people
	Anti-Oxidant Enzyme Profile	Improves (the measure goes up)			33 people
	Blood Pressure	Changes; see studies			144 people
	Body Fat	Changes; see studies			144 people
	Endothelin-1	Improves (the measure goes up)			33 people
	Glycemic Control	Improves (the measure goes up)			144 people
	HbA1c	Changes; see studies			144 people
	Muscle Mass	Improves (the measure goes up)			144 people

Obesity

Adiponectin: improves
Nitric Oxide: improves
Vascular Function: improves

Obesity: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People
	Adiponectin Small Increase	Improves (the measure goes up)	Small effect		33 people
	Nitric Oxide	Improves (the measure goes up)		4 studies	33 people
Studies that measured nitric oxide Beneficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulin-resistant type 2 diabetic patientsAm J Physiol Endocrinol Metab · PMID 16772327 No effect of short-term arginine supplementation on nitric oxide production, metabolism and performance in intermittent exercise in athletesJ Nutr Biochem · PMID 18708287 Effects of 7 days of arginine-alpha-ketoglutarate supplementation on blood flow, plasma L-arginine, nitric oxide metabolites, and asymmetric dimethyl arginine after resistance exerciseInt J Sport Nutr Exerc Metab · PMID 21813912 Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolismBr J Clin Pharmacol · PMID 17662090
	Vascular Function	Improves (the measure goes up)		1 study	33 people
Studies that measured vascular function Hemodynamic and vascular response to resistance exercise with L-arginineMed Sci Sports Exerc · PMID 19276857
	Anti-Oxidant Enzyme Profile	Improves (the measure goes up)			33 people
	Endothelin-1	Improves (the measure goes up)			33 people

Anaerobic Exercise Performance

Anaerobic Capacity: improves
Nitric Oxide: improves
Oxygen Cost of Exercise: improves

Anaerobic Exercise Performance: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People
	Anaerobic Capacity Small Improvement	Improves (the measure goes up)	Small effect		9 people
	Nitric Oxide	Improves (the measure goes up)		4 studies	9 people
Studies that measured nitric oxide Beneficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulin-resistant type 2 diabetic patientsAm J Physiol Endocrinol Metab · PMID 16772327 No effect of short-term arginine supplementation on nitric oxide production, metabolism and performance in intermittent exercise in athletesJ Nutr Biochem · PMID 18708287 Effects of 7 days of arginine-alpha-ketoglutarate supplementation on blood flow, plasma L-arginine, nitric oxide metabolites, and asymmetric dimethyl arginine after resistance exerciseInt J Sport Nutr Exerc Metab · PMID 21813912 Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolismBr J Clin Pharmacol · PMID 17662090
	Oxygen Cost of Exercise	Improves (the measure goes up)			9 people

Metabolic Health

Ammonia

Metabolic Health: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Ammonia No effect		NoneNo effect		10 people

High Cholesterol

C-Reactive Protein (CRP)
Total cholesterol: changes; see studies
Triglycerides: changes; see studies

High Cholesterol: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People
	C-Reactive Protein (CRP) No effect		NoneNo effect		643 people
	Total cholesterol	Changes; see studies		1 study	643 people
Studies that measured total cholesterol The effect of l-arginine supplementation on lipid profile: a systematic review and meta-analysis of randomised controlled trials.Br J Nutr · PMID 31922465
	Triglycerides	Changes; see studies		1 study	643 people
Studies that measured triglycerides Effect of L-Arginine supplementation on lipid profiles and inflammatory markers: A systematic review and meta-analysis of randomized controlled trials.Pharmacol Res · PMID 31442577
	High-density lipoprotein (HDL)	Improves (the measure goes up)			643 people
	Low-density lipoprotein (LDL)	Changes; see studies			643 people
	TNF-Alpha	Changes; see studies			643 people

Cycling Performance

Ammonia
Nitric Oxide: improves
Growth Hormone: improves

Cycling Performance: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People
	Ammonia No effect		NoneNo effect		10 people
	Nitric Oxide	Improves (the measure goes up)		4 studies	10 people
Studies that measured nitric oxide Beneficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulin-resistant type 2 diabetic patientsAm J Physiol Endocrinol Metab · PMID 16772327 No effect of short-term arginine supplementation on nitric oxide production, metabolism and performance in intermittent exercise in athletesJ Nutr Biochem · PMID 18708287 Effects of 7 days of arginine-alpha-ketoglutarate supplementation on blood flow, plasma L-arginine, nitric oxide metabolites, and asymmetric dimethyl arginine after resistance exerciseInt J Sport Nutr Exerc Metab · PMID 21813912 Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolismBr J Clin Pharmacol · PMID 17662090
	Growth Hormone	Improves (the measure goes up)		3 studies	30 people
Studies that measured growth hormone Growth hormone responses to varying doses of oral arginineGrowth Horm IGF Res · PMID 15809017 Oral arginine does not stimulate basal or augment exercise-induced GH secretion in either young or old adultsJ Gerontol A Biol Sci Med Sci · PMID 10496544 Influence of chronic supplementation of arginine aspartate in endurance athletes on performance and substrate metabolism - a randomized, double-blind, placebo-controlled studyInt J Sports Med · PMID 15895316
	Plasma Arginine	Improves (the measure goes up)		2 studies	10 people
Studies that measured plasma arginine L-arginine supplementation in peripheral arterial disease: no benefit and possible harmCirculation · PMID 17592080 L-arginine-induced vasodilation in healthy humans: pharmacokinetic-pharmacodynamic relationshipBr J Clin Pharmacol · PMID 9833603
	Blood Lactate (Exercise)	Changes; see studies			30 people
	Cortisol	Changes; see studies			30 people
	Glucagon	Changes; see studies			30 people
	Oxygen Cost of Exercise	Improves (the measure goes up)			30 people
	Plasma Nitrate	Improves (the measure goes up)			10 people
	Power Output	Improves (the measure goes up)			10 people
	Testosterone	Improves (the measure goes up)			30 people
	Urea	Improves (the measure goes up)			30 people

Dyslipidemia

C-Reactive Protein (CRP)
Total cholesterol: changes; see studies
Triglycerides: changes; see studies

Dyslipidemia: outcomes studied for Arginine
Outcome	Effect	Size	Studies	People
C-Reactive Protein (CRP) No effect		NoneNo effect		643 people
Total cholesterol	Changes; see studies		1 study	643 people
Triglycerides	Changes; see studies		1 study	643 people
High-density lipoprotein (HDL)	Improves (the measure goes up)			643 people
Low-density lipoprotein (LDL)	Changes; see studies			643 people
TNF-Alpha	Changes; see studies			643 people

Peripheral Arterial Disease

Asymmetric dimethylarginine (aka ADMA)
Nitric Oxide: improves
Plasma Arginine: improves

Peripheral Arterial Disease: outcomes studied for Arginine
Outcome	Effect	Size	Studies	People
Asymmetric dimethylarginine (aka ADMA) No effect		NoneNo effect		133 people
Nitric Oxide	Improves (the measure goes up)		4 studies	38 people
Plasma Arginine	Improves (the measure goes up)		2 studies	133 people
Blood Flow	Improves (the measure goes up)		1 study	133 people
Blood glucose	Changes; see studies		1 study	38 people
Oxidative Stress Biomarkers	Changes; see studies		1 study	38 people
HbA1c	Changes; see studies			38 people
Intermittent Claudication Symptoms	Changes; see studies			133 people
Subjective Well-Being	Improves (the measure goes up)			133 people

Healthy Muscle Aging

Growth Hormone: improves

Healthy Muscle Aging: outcomes studied for Arginine
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Growth Hormone	Improves (the measure goes up)		3 studies	28 people

Key findings

Blood FlowImproves (the measure goes up)
Anaerobic CapacityGeneral Athletic PerformanceImproves (the measure goes up)
AdiponectinType 2 DiabetesImproves (the measure goes up)

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Grade C

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Studies cited

17 studies from PubMed

Effect of a long-term oral l-arginine supplementation on glucose metabolism: a randomized, double-blind, placebo-controlled trialDiabetes Obes Metab · PMID 22553931
Beneficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulin-resistant type 2 diabetic patientsAm J Physiol Endocrinol Metab · PMID 16772327
The effect of oral L-arginine supplementation on fasting glucose, HbA1c, nitric oxide and total antioxidant status in diabetic patients with atherosclerotic peripheral arterial disease of lower extremitiesEur Rev Med Pharmacol Sci · PMID 22530351
A study of growth hormone release in man after oral administration of amino acidsCurr Med Res Opin · PMID 6790230
Growth hormone responses to varying doses of oral arginineGrowth Horm IGF Res · PMID 15809017
No effect of short-term arginine supplementation on nitric oxide production, metabolism and performance in intermittent exercise in athletesJ Nutr Biochem · PMID 18708287
L-arginine supplementation in peripheral arterial disease: no benefit and possible harmCirculation · PMID 17592080
Effects of 7 days of arginine-alpha-ketoglutarate supplementation on blood flow, plasma L-arginine, nitric oxide metabolites, and asymmetric dimethyl arginine after resistance exerciseInt J Sport Nutr Exerc Metab · PMID 21813912
Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolismBr J Clin Pharmacol · PMID 17662090
Hemodynamic and vascular response to resistance exercise with L-arginineMed Sci Sports Exerc · PMID 19276857
L-arginine-induced vasodilation in healthy humans: pharmacokinetic-pharmacodynamic relationshipBr J Clin Pharmacol · PMID 9833603
Effect of L-Arginine supplementation on lipid profiles and inflammatory markers: A systematic review and meta-analysis of randomized controlled trials.Pharmacol Res · PMID 31442577
Oral arginine does not stimulate basal or augment exercise-induced GH secretion in either young or old adultsJ Gerontol A Biol Sci Med Sci · PMID 10496544
Acute L-arginine alpha ketoglutarate supplementation fails to improve muscular performance in resistance trained and untrained menJ Int Soc Sports Nutr · PMID 22510253
Restoring vascular nitric oxide formation by L-arginine improves the symptoms of intermittent claudication in patients with peripheral arterial occlusive diseaseJ Am Coll Cardiol · PMID 9809945
Influence of chronic supplementation of arginine aspartate in endurance athletes on performance and substrate metabolism - a randomized, double-blind, placebo-controlled studyInt J Sports Med · PMID 15895316
The effect of l-arginine supplementation on lipid profile: a systematic review and meta-analysis of randomised controlled trials.Br J Nutr · PMID 31922465