L-Tyrosine is an amino acid (building block of protein) that is “conditionally essential,” as generally it must be supplied by the diet, although it can be produced from the essential amino acid L-Phenylalanine (a process dependent upon vitamin B-6). (L-tyrosine is essential for individuals with phenoketonuria, who cannot produce L-Tyrosine from L-Phenylalanine.) L-Tyrosine is the precursor to the thyroid hormones, as well the catecholamines, dopamine, norepinephrine and epinephrine. As such, deficiency can have far-reaching affects on metabolic rate and neural regulation of the sympathetic nervous system(1-3), including central effects on mood and memory(4, 5). In particular, supplementing with L-Tyrosine may enhance arousal and therefore performance during high intensity exercise, such as weight training (6). During a fat-loss regimen that includes thermogenic supplements such as ephedrine or Green Tea Extract, L-Tyrosine may enhance the anorectic (appetite suppressing) actions of these supplements(7).
L-Tyrosine (5-10g / day) can be used to enhance cognitive performance during times of stress, high-intensity and possibly endurance exercise. L-Tyrosine can be taken to ensure optimal thyroid function when attempting to lose body fat with diet and exercise, as well as enhance the appetite-suppressant effects of thermogenics. L-Tyrosine might also be combined with with DL-Phenylalanine to treat depression. Individuals with phenylketonurics should refer to their physician if attempting to use this supplement.
As a dietary supplement, take 1 Serving (500mg) up to 20-40 times daily, spread evenly throughout the day or as advised by a medical professional.
Packaged in heat-sealed foil pouches.
If you are currently pregnant or nursing, consult a physician prior to use. Keep out of the reach of children.
This product is free from all forms of shell fish, tree nuts, yeast, gluten, salt, preservatives, lactose, and soy. This product is manufactured in a facility that handles soy, gluten, and milk products. Products ordered using Premium Flavor Systems will contain artificial flavoring and sweeteners. This product is manufactured in a facility that handles milk, soy, egg, peanut, nut, tree, fish, crustaceans/shellfish, and wheat products.
Use the table below to approximate the gram equivalent weight for a given level measuring spoon (US Standard). Please note that accurate dosing should only be done with a recommended calibrated scale.
|Measuring Spoon (level)
DISCLAIMER: The above description is provided for information only and does not constitute medical advice. Please consult your physician or the appropriately licensed professional before engaging in a program of exercise or nutritional supplementation. No information in this site has been reviewed by the FDA. No product is intended to treat, diagnose, or cure any disease.
1. Tahara, Y., et al., Primary hypothyroidism in an adult patient with protein-calorie malnutrition: a study of its mechanism and the effect of amino acid deficiency. Metabolism, 1988. 37(1): p. 9-14. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=3121981
2. Schweiger, U., et al., Brain tyrosine availability and the depression of central nervous norepinephrine turnover in acute and chronic starvation in adult male rats. Brain Res, 1985. 335(2): p. 207-12. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=4005550
3. Elkin, R.G., et al., Effects of dietary phenylalanine and tyrosine on circulating thyroid hormone levels and growth in the chick. J Nutr, 1980. 110(1): p. 132-8. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=7354377
4. McTavish, S.F., et al., Lack of effect of tyrosine depletion on mood in recovered depressed women. Neuropsychopharmacology, 2005. 30(4): p. 786-91. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15702140
5. Roiser, J.P., et al., The subjective and cognitive effects of acute phenylalanine and tyrosine depletion in patients recovered from depression. Neuropsychopharmacology, 2005. 30(4): p. 775-85. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15688090
6. Meeusen, R., et al., The brain and fatigue: new opportunities for nutritional interventions? J Sports Sci, 2006. 24(7): p. 773-82. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=16766505
7. Hull, K.M. and T.J. Maher, L-tyrosine fails to potentiate several peripheral actions of the sympathomimetics. Pharmacol Biochem Behav, 1991. 39(3): p. 755-9.