L-Tyrosine

    Written by:
    Bill Willis

    Fact-checked

    by:

    Nick Milazzo
    Last Updated: July 16, 2024

    L-Tyrosine is an amino acid that is used as a precursor for the synthesis of the catecholamines dopamine (DA) and norepinephrine (NE). DA and NE are depleted under stressful conditions, which can compromise cognitive function. L-Tyrosine supplementation may help alleviate acute stress-induced cognitive decline by restoring catecholamine levels in the brain.

    28 references on this page
    546 participants in 27 trials

    Overview

    Dosage information

    Anecdotally, L-Tyrosine tends to be taken in doses of 500–2000 mg approximately 30–60 minutes before any acute stressor (this tends to be exercise).

    Studies in humans showing most anti-stress promise for acute supplemental L-Tyrosine use a dosage range of 100–150 mg/kg of bodyweight which can be taken 60 minutes before exercise; this is a dosage range of 9–13.5 g for a 200 lb person and 7–10 g for a 150 lb person.

    If using higher doses and finding digestive issues, this may be split into two doses separated by half an hour (30 and 60 minutes prior to acute stress).

    Frequently asked questions

    Update History

    Research Breakdown

    Examine Database References

    1. Heart Rate - A B Dollins, L P Krock, W F Storm, R J Wurtman, H R LiebermanL-tyrosine ameliorates some effects of lower body negative pressure stressPhysiol Behav.(1995 Feb)
    2. Body Temperature - James A Lang, Alex C Krajek, Kelsey S Schwartz, Joel E RandOral L-Tyrosine Supplementation Improves Core Temperature Maintenance in Older AdultsMed Sci Sports Exerc.(2020 Apr)
    3. Processing Accuracy - Thomas J, Lockwood P, Singh, A, Patricia, DTyrosine Improves Working Memory in a Multitasking EnvironmentPharmacol Biochem.()
    4. Reaction Time - Catherine O'Brien, Caroline Mahoney, William J Tharion, Ingrid V Sils, John W CastellaniDietary tyrosine benefits cognitive and psychomotor performance during body coolingPhysiol Behav.(2007 Feb 28)
    5. Working Memory - Deijen JB, Orlebeke JFEffect of tyrosine on cognitive function and blood pressure under stressBrain Res Bull.(1994)
    6. Working Memory - Ondine van de Rest, Mirjam Bloemendaal, Rianne de Heus, Esther AartsDose-Dependent Effects of Oral Tyrosine Administration on Plasma Tyrosine Levels and Cognition in AgingNutrients.(2017 Nov 23)
    7. Working Memory - Shurtleff D, Thomas JR, Schrot J, Kowalski K, Harford RTyrosine reverses a cold-induced working memory deficit in humansPharmacol Biochem Behav.(1994 Apr)
    8. Working Memory - Deijen JB, Wientjes CJ, Vullinghs HF, Cloin PA, Langefeld JJTyrosine improves cognitive performance and reduces blood pressure in cadets after one week of a combat training courseBrain Res Bull.(1999 Jan 15)
    9. Working Memory - Neri DF, Wiegmann D, Stanny RR, Shappell SA, McCardie A, McKay DLThe effects of tyrosine on cognitive performance during extended wakefulnessAviat Space Environ Med.(1995 Apr)
    10. Alertness - Nicole A Coull, Samuel L Watkins, Jeffrey W F Aldous, Lee K Warren, Bryna C R Chrismas, Benjamin Dascombe, Alexis R Mauger, Grant Abt, Lee TaylorEffect of tyrosine ingestion on cognitive and physical performance utilising an intermittent soccer performance test (iSPT) in a warm environmentEur J Appl Physiol.(2015 Feb)
    11. Rating of Perceived Exertion - Les Tumilty, Nicholas Gregory, Manfred Beckmann, Rhys ThatcherNo Influence of Low-, Medium-, or High-Dose Tyrosine on Exercise in a Warm EnvironmentMed Sci Sports Exerc.(2020 Jun)
    12. Rating of Perceived Exertion - Les Tumilty, Glen Davison, Manfred Beckmann, Rhys ThatcherFailure of oral tyrosine supplementation to improve exercise performance in the heatMed Sci Sports Exerc.(2014 Jul)
    13. Rating of Perceived Exertion - Les Tumilty, Glen Davison, Manfred Beckmann, Rhys ThatcherOral tyrosine supplementation improves exercise capacity in the heatEur J Appl Physiol.(2011 Dec)
    14. Dopamine - D D Rasmussen, B Ishizuka, M E Quigley, S S YenEffects of tyrosine and tryptophan ingestion on plasma catecholamine and 3,4-dihydroxyphenylacetic acid concentrationsJ Clin Endocrinol Metab.(1983 Oct)
    15. Dopamine - Li J, Zie FEffects of tyrosine supplementation ration on anaerobic sports capacity and plasma catecholamine levels in soccer athletesBiomed Res.()
    16. Renin Activity - C R Benedict, G H Anderson, M J SoleThe influence of oral tyrosine and tryptophan feeding on plasma catecholamines in manAm J Clin Nutr.(1983 Sep)
    17. Heart Rate - James A Lang, Kevin A SmallerOral l-tyrosine supplementation augments the vasoconstriction response to whole-body cooling in older adultsExp Physiol.(2017 Jul 1)
    18. Heart Rate - Troy D Chinevere, Robert D Sawyer, Andrew R Creer, Robert K Conlee, Allen C ParcellEffects of L-tyrosine and carbohydrate ingestion on endurance exercise performanceJ Appl Physiol (1985).(2002 Nov)
    19. Blood glucose - Erin E Sutton, M Regina Coill, Patricia A DeusterIngestion of tyrosine: effects on endurance, muscle strength, and anaerobic performanceInt J Sport Nutr Exerc Metab.(2005 Apr)
    20. Working Memory - Banderet LE, Lieberman HRTreatment with tyrosine, a neurotransmitter precursor, reduces environmental stress in humansBrain Res Bull.(1989 Apr)
    21. Fatigue Symptoms - Harris R Lieberman, Lauren A Thompson, Christina M Caruso, Philip J Niro, Caroline R Mahoney, James P McClung, Gregory R CaronThe catecholamine neurotransmitter precursor tyrosine increases anger during exposure to severe psychological stressPsychopharmacology (Berl).(2015 Mar)
    22. Heart Rate - Joanne DiFrancisco-Donoghue, Ely Rabin, Eric M Lamberg, William G WernerEffects of Tyrosine on Parkinson's Disease: A Randomized, Double-Blind, Placebo-Controlled TrialMov Disord Clin Pract.(2014 Oct 23)
    23. Schizophrenia symptoms - Deutsch SI, Rosse RB, Schwartz BL, Banay-Schwartz M, McCarthy MF, Johri SKL-tyrosine pharmacotherapy of schizophrenia: preliminary dataClin Neuropharmacol.(1994 Feb)
    24. Impulse Control - Lorenza S Colzato, Bryant J Jongkees, Roberta Sellaro, Wery P M van den Wildenberg, Bernhard HommelEating to stop: tyrosine supplementation enhances inhibitory control but not response executionNeuropsychologia.(2014 Sep)
    25. Narcolepsy Symptoms - R D Elwes, H Crewes, L P Chesterman, B Summers, P Jenner, C D Binnie, J D ParkesTreatment of narcolepsy with L-tyrosine: double-blind placebo-controlled trialLancet.(1989 Nov 4)
    26. Heart Rate - M J Sole, C R Benedict, M G Myers, F H Leenen, G H AndersonChronic dietary tyrosine supplements do not affect mild essential hypertensionHypertension.(Jul-Aug 1985)
    27. Depression Symptoms - A J Gelenberg, J D Wojcik, W E Falk, R J Baldessarini, S H Zeisel, D Schoenfeld, G S MokTyrosine for depression: a double-blind trialJ Affect Disord.(1990 Jun)