L-arginine
Three meta-analyses found blood pressure lower with L-arginine, systolic by about 4 to 6 mmHg. In mild to moderate erectile dysfunction, pooled trials found 3.4 times the odds of improvement. Performance results disagree, and a published comment found errors in the main meta-analysis. In a heart attack trial, 6 of 70 on L-arginine died against none on placebo.
Add to Bio HackChecked 2026-11-12
- Status
- Dietary supplement in the US. Arginine is also an ingredient in some toothpastes.
- Also called
- arginine, L-arg, arginine HCl, arginine alpha-ketoglutarate, AAKG, nitric oxide booster, NO booster, pump supplement
- Taken for
- blood flow, pump, nitric oxide, erectile function, blood pressure, exercise performance, strength, growth hormone, height in children, cavities, sensitive teeth
Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on
Shown to help4
- StrongShown to lower blood pressure about 5 to 6 mmHg systolic and 2.6 mmHg diastolic in adults. Doses above 9 g a day and obese participants showed no change.
- ModerateArginine toothpaste was shown to ease tooth sensitivity more than other desensitizing toothpastes at 4 and 8 weeks in adults, with no difference beyond 12 weeks.
- ModerateShown to raise the odds of improvement about 3 times over placebo in men with mild to moderate erectile dysfunction, at 1,500 to 5,000 mg a day.
- LimitedLimited evidence: oral arginine raised growth speed about 0.6 cm a year in children with idiopathic short stature, in low-quality studies.
What people take it for, and what was found
Shown to help4
Blood pressure
Shown to lower blood pressure about 5 to 6 mmHg systolic and 2.6 mmHg diastolic in adults. Doses above 9 g a day and obese participants showed no change.
The numbers and sources
- Effect
- Across 11 trials with 387 participants taking 4 to 24 g a day, systolic pressure fell 5.39 mmHg (95% CI -8.54 to -2.25) and diastolic 2.66 mmHg (95% CI -3.77 to -1.54) [1]. Across 22 RCTs, systolic fell 6.40 mmHg (95% CI -8.74 to -4.05) and diastolic 2.64 mmHg. Doses above 9 g a day, trials longer than 24 days and obese participants showed no significant change [2]. In 5 RCTs with 202 participants using ambulatory monitoring, 24-hour systolic fell 4.23 mmHg (95% CI -5.87 to -2.58) and diastolic 3.04 mmHg [3].
- Population
- Adults with and without hypertension in RCTs [1][2][3].
- Sources
- [1], [2], [3]
- Caveats
- Trials were small. The ambulatory analysis included 5 trials [3].
Tooth sensitivity: arginine toothpaste (topical)
Arginine toothpaste was shown to ease tooth sensitivity more than other desensitizing toothpastes at 4 and 8 weeks in adults, with no difference beyond 12 weeks.
The numbers and sources
- Effect
- Across 18 RCTs (1,423 patients), arginine toothpaste improved touch sensitivity (SMD 1.95, 95% CI 1.14 to 2.76) and air-blast sensitivity (SMD -1.60, 95% CI -2.14 to -1.05) at 4 weeks against toothpastes with other desensitizing ingredients, and both again at 8 weeks (SMD 2.01 and -1.41). Air-blast scores did not differ at days 0 and 3 or week 2, and neither test differed beyond 12 weeks [4]. Across 14 RCTs, arginine toothpaste reduced sensitivity more than placebo, potassium and strontium toothpastes, reported as p values below 0.05 [5]. A third review found a potential role from small trials without medium or long-term follow-up [6].
- Population
- Adults with dentin hypersensitivity in RCTs [4][5][6].
- Sources
- [4], [5], [6]
- Caveats
- This is toothpaste applied to the teeth, not oral arginine. GRADE quality was moderate against placebo and potassium and low against strontium [5]. Samples were small [6].
Erectile function
Shown to raise the odds of improvement about 3 times over placebo in men with mild to moderate erectile dysfunction, at 1,500 to 5,000 mg a day.
The numbers and sources
- Effect
- In 10 RCTs with 540 men with mild to moderate erectile dysfunction, 1,500 to 5,000 mg of arginine raised the odds of improvement over placebo or no treatment (OR 3.37, 95% CI 1.29 to 8.77, I² 44%). IIEF erectile function, orgasmic function and satisfaction scores improved, and sexual desire did not change [7].
- Population
- Men with mild to moderate erectile dysfunction [7].
- Sources
- [7]
- Caveats
- Doses and durations varied. The analysis included arginine combined with other substances alongside arginine alone [7].
Height growth in children with short stature
Limited evidence: oral arginine raised growth speed about 0.6 cm a year in children with idiopathic short stature, in low-quality studies.
The numbers and sources
- Effect
- Oral arginine for 6 or 12 months raised growth velocity (SMD 0.66, 95% CI 0.21 to 1.12), equal to 0.59 cm a year (95% CI 0.19 to 1.00). The effect was not significant in studies giving it for 12 months only [14].
- Population
- Prepubertal children with idiopathic short stature, in clinical trials and cohort studies [14].
- Sources
- [14]
- Caveats
- The authors found only low-quality studies [14]. Growth hormone levels were not reported in the abstract.
Mixed results3
Cavities: arginine toothpaste (topical)
Mixed results: one review found arginine toothpaste with fluoride lowered early cavities, and another found the evidence insufficient.
The numbers and sources
- Effect
- Sources disagree. A meta-analysis of 7 studies found that arginine with fluoride lowered early coronal and root cavities more than placebo or fluoride alone, and the abstract reports no effect sizes [8]. A second review found the evidence insufficient for a cavity-preventing effect of adding arginine to toothpaste. It drew no conclusions on children's studies because of conflicts of interest, and noted that control children in several studies used non-fluoride toothpaste [9].
- Population
- 10 studies with 15,546 participants [8]. RCTs in children, adults and older adults [9].
- Sources
- [8], [9]
- Caveats
- This is toothpaste applied to the teeth, not oral arginine. The first review downgraded its evidence for risk of bias and possible publication bias, and called for trials not supported by industry [8].
Exercise performance
Limited evidence: one review reported better aerobic and anaerobic performance but was found to contain errors, and strength trials found no effect.
The numbers and sources
- Effect
- A meta-analysis of 15 studies reported improved aerobic performance (SMD 0.84, 95% CI 0.12 to 1.56, I² 89%) and anaerobic performance (SMD 0.24, 95% CI 0.05 to 0.43) [10]. A 2025 published comment identified errors in that analysis, including outlier effect sizes, effect estimates that needed recalculating with standard deviations, and one included study that appeared to compare arginine with citrulline rather than placebo [11]. A meta-analysis of 3 trials of acute arginine alone in strength training found no effect on muscular endurance (0.26, 95% CI -0.13 to 0.65) or peak torque [12]. In a crossover trial of 4 days at 3.2 to 9.6 g a day, total biceps curl repetitions, volume load, fatigue and plasma nitric oxide did not differ from placebo [13].
- Population
- Athletes and active adults [10][12]. 16 recreationally trained young men [13].
- Sources
- [10], [11], [12], [13]
- Caveats
- Sources disagree. Aerobic results had very high heterogeneity [10].
Growth hormone and muscle growth
Mixed results: small trials found oral arginine raised resting growth hormone but blunted its rise after lifting, and lean mass did not change in athletes over 45 days.
The numbers and sources
- Effect
- In 8 healthy men, 5 g and 9 g of oral arginine raised the growth hormone area under the curve over placebo at rest, while 13 g did not and caused stomach upset in most [16]. In 8 men, 7 g of arginine before resistance exercise gave a smaller growth hormone response than exercise alone [17]. In 14 strength-trained men, arginine before lifting blunted growth hormone (area under the curve 288.4 against 487.9 on placebo, p < 0.05), with no difference in IGF-1 [18]. In 56 male soccer players, 2 g a day for 45 days did not change lean body mass, fat mass or BMI against placebo [19].
- Population
- Healthy young men [16][17]. Strength-trained men [18]. Male soccer players aged 16 to 35 [19].
- Sources
- [16], [17], [18], [19]
- Caveats
- Small, short trials in men. Growth hormone was measured for hours after a single dose, and no trial measured muscle growth over a training program [16][17][18].
Doses studied
Blood pressure trials used 4 to 24 g a day [1]. In the 2022 analysis, systolic reductions appeared from 4 g a day, and doses above 9 g showed no significant change [2]. Erectile dysfunction trials used 1,500 to 5,000 mg a day [7]. The performance meta-analysis described acute doses of 0.15 g/kg body weight 60 to 90 minutes before exercise, and chronic doses of 1.5 to 2 g a day for 4 to 7 weeks or 10 to 12 g a day for 8 weeks [10]. The heart attack trial targeted 3 g three times a day for 6 months [15].
Risks
Reported risks2
Deaths after heart attack
One trial was stopped early after 6 people on L-arginine died against none on placebo, in patients after a first heart attack.
The numbers and sources
- How common
- Common: between 1 in 100 and 1 in 10 people.
- Effect
- In 153 patients after a first ST-elevation heart attack, adding L-arginine at a goal of 3 g three times a day to standard care did not improve vascular stiffness or ejection fraction over 6 months. Six participants (8.6%) on L-arginine died against none on placebo (p = 0.01), and the safety committee closed enrollment [15].
- Population
- Heart attack patients, 77 aged 60 or older [15].
- Sources
- [15]
- Caveats
- One trial stopped early. Supported by the NHLBI [15].
Side effects in erectile dysfunction trials
Shown to raise side effects to 8.3% against 2.3% on placebo in men with erectile dysfunction, none severe.
Checked, no increase found1
Side effects of arginine toothpaste (topical)
No specific side effects of arginine toothpaste were identified across 10 cavity studies of 15,546 people.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- No specific side effects related to arginine were identified across 10 cavity studies with 15,546 participants [8].
- Population
- Children and adults using arginine toothpaste [8].
- Sources
- [8]
- Caveats
- Topical use only. The abstract does not describe how side effects were collected.
Claims tested and not found
- That L-arginine improves strength training performance. Acute arginine alone did not change muscular endurance or peak torque across 3 trials [12], and 4 days of use did not change biceps curl repetitions [13].
- That L-arginine improves heart function after a heart attack. Ejection fraction and vascular stiffness did not change over 6 months [15].
- That arginine raises sexual desire. The IIEF sexual desire score did not change in pooled trials [7].
Sources
- Dong JY, Qin LQ, Zhang Z, et al. Effect of oral L-arginine supplementation on blood pressure: A meta-analysis of randomized, double-blind, placebo-controlled trials. American Heart Journal. 2011. https://doi.org/10.1016/j.ahj.2011.09.012
- Shiraseb F, Asbaghi O, Bagheri R, et al. Effect of L-Arginine Supplementation on Blood Pressure in Adults: A Systematic Review and Dose-Response Meta-analysis of Randomized Clinical Trials. Advances in Nutrition. 2022. https://doi.org/10.1093/advances/nmab155
- Shi Y, Liu Y, Zhou Z, et al. Reassessment of the effect of oral L-arginine on blood pressure: A systematic review and meta-analysis based on ambulatory blood pressure monitoring. Nitric Oxide. 2026. https://doi.org/10.1016/j.niox.2026.07.004
- Yang ZY, Wang F, Lu K, et al. Arginine-containing desensitizing toothpaste for the treatment of dentin hypersensitivity: a meta-analysis. Clinical, Cosmetic and Investigational Dentistry. 2016. https://doi.org/10.2147/CCIDE.S95660
- Yan B, Yi J, Li Y, et al. Arginine-containing toothpastes for dentin hypersensitivity: systematic review and meta-analysis. Quintessence International. 2013. https://pubmed.ncbi.nlm.nih.gov/23878846/
- Sharif MO, Iram S, Brunton PA. Effectiveness of arginine-containing toothpastes in treating dentine hypersensitivity: a systematic review. Journal of Dentistry. 2013. https://doi.org/10.1016/j.jdent.2013.01.009
- Rhim HC, Kim MS, Park YJ, et al. The Potential Role of Arginine Supplements on Erectile Dysfunction: A Systemic Review and Meta-Analysis. Journal of Sexual Medicine. 2019. https://doi.org/10.1016/j.jsxm.2018.12.002
- Li J, Huang Z, Mei L, et al. Anti-Caries Effect of Arginine-Containing Formulations in vivo: A Systematic Review and Meta-Analysis. Caries Research. 2015. https://doi.org/10.1159/000435894
- Ástvaldsdóttir Á, Naimi-Akbar A, Davidson T, et al. Arginine and Caries Prevention: A Systematic Review. Caries Research. 2016. https://doi.org/10.1159/000446249
- Viribay A, Burgos J, Fernández-Landa J, et al. Effects of Arginine Supplementation on Athletic Performance Based on Energy Metabolism: A Systematic Review and Meta-Analysis. Nutrients. 2020. https://doi.org/10.3390/nu12051300
- Trexler ET. Common Errors in Sports Nutrition Meta-Analyses Lead to Distortion of Pooled Effect Estimates. Comment on Viribay et al. Effects of Arginine Supplementation on Athletic Performance Based on Energy Metabolism: A Systematic Review and Meta-Analysis. Nutrients. 2025. https://doi.org/10.3390/nu17142375
- Pasa C, Godinho de Oliveira R, da Rosa Lima T, et al. Effectiveness of acute L-arginine supplementation on physical performance in strength training: a systematic review and meta-analysis. F1000Research. 2022. https://doi.org/10.12688/f1000research.73905.2
- Borges CC, Alves da Silva W, de Sá Filho AS, et al. Effect of Arginine Supplementation on Vasodilation and Muscular Performance in Young Men: A Randomized, Double-Blind, Crossover Study. International Journal of Sport Nutrition and Exercise Metabolism. 2026. https://doi.org/10.1123/ijsnem.2025-0125
- Virú-Loza MA, Chávez-Nomberto RE, Hernandez AV. Efficacy of Oral Arginine as Treatment to Improve Height in Prepubertal Children With Idiopathic Short Stature: A Systematic Review and Meta-Analysis. Sage Open Pediatrics. 2026. https://doi.org/10.1177/30502225261433767
- Schulman SP, Becker LC, Kass DA, et al. L-Arginine Therapy in Acute Myocardial Infarction: The Vascular Interaction With Age in Myocardial Infarction (VINTAGE MI) Randomized Clinical Trial. JAMA. 2006. https://doi.org/10.1001/jama.295.1.58
- Collier SR, Casey DP, Kanaley JA. Growth hormone responses to varying doses of oral arginine. Growth Hormone & IGF Research. 2005. https://doi.org/10.1016/j.ghir.2004.12.004
- Collier SR, Collins E, Kanaley JA. Oral arginine attenuates the growth hormone response to resistance exercise. Journal of Applied Physiology. 2006. https://doi.org/10.1152/japplphysiol.00285.2006
- Forbes SC, Harber V, Bell GJ. Oral L-arginine before resistance exercise blunts growth hormone in strength trained males. International Journal of Sport Nutrition and Exercise Metabolism. 2014. https://doi.org/10.1123/ijsnem.2013-0106
- Pahlavani N, Entezari MH, Nasiri M, et al. The effect of l-arginine supplementation on body composition and performance in male athletes: a double-blinded randomized clinical trial. European Journal of Clinical Nutrition. 2017. https://doi.org/10.1038/ejcn.2016.266