Table of Contents
What is Phenylalanine ?
L-Phenylalanine is an essential amino acid, which means that the body needs this ingredient and cannot be produced naturally.
Phenylalanine (which is converted to phenylethylamine) must be obtained through dietary supplements or through food sources including meat and dairy products, oat and wheat germ products.
For this supplement to be most effective, the body also needs vitamins B3, B6, C, copper and iron.
L-Phenylalanine as an amino acid helps to produce proteins in the body. There are also several different forms of this supplement: L-phenylalanine, D-phenylalanine, and DL-phenylalanine (the last combination of the two closest forms).
This dietary supplement is important for the normal functioning of the central nervous system.
It is also used for the formation and synthesis of various neurotransmitters such as epinephrine, dopamine and norepinephrine. All these chemicals are very important for the proper functioning of the nervous system.
Although the specific mechanisms of action are still not fully understood, this dietary supplement is known to cross the blood-brain-barrier and enter the central nervous system.
This “barrier” is a protective function of red blood cells and the brain that prevents the entry of toxins, bacteria or viruses into the brain and nervous system. However, this barrier also retains many potentially useful compounds. The ability of it to cross the blood brain barrier is integral to its effectiveness as a cognitive enhancer.
One of the most important ways this dietary supplement works is thought to be the synthesis of neurotransmitters, especially dopamine, norepinephrine and epinephrine. Recent studies also show that it helps to produce melatonin (which is vital for controlling and regulating sleep and wake cycles).
This supplement is for tyrosine, another amino acid. Tyrosine itself is thought to be beneficial in anxiety and depression. It is also important for proper metabolic function and can help in reducing body fat.
Signals that transmit information from the neuron to the neuron are executed faster and more efficiently.
This essential amino acid found in protein-rich foods: dairy products, eggs, meat, fish, legumes, and more.
However, the source of phenylalanine, which needs to be restricted so for people with phenylketonuria, is any food product sweetened with aspartame, usually protein-free, such as a carbonated drink.
Phenylketonuria is used to label food products with information on the source of phenylalanine (even where it is not expected) and special labeling.
Phenylalanine appears to have a fairly wide range of effective doses.
Clinical trials used anywhere from 100 mg to 5000 mg daily. Typical users follow a dose of 1000 to 2000 mg per day.
It is also common to take a L-Phenylalanine supplement with hordenin, which is a compound that prevents the breakdown of this nootropic. The result is a longer exposure to phenylalanine and a marked improvement in mood.
Phenylalanine Side Effects
While this dietary supplement is generally considered safe and very well tolerated, there are some associated side effects. This is nausea, headache. This information should also not be used by people who are currently using antispirers and specific antidepressants (monoamine oxidase inhibitors – MAOIs). Always consult your doctor or a qualified medical professional before using this or any other dietary supplement.
- Tumilty L, Davison G, Beckmann M, Thatcher R. Acute oral administration of a tyrosine and phenylalanine-free amino acid mixture reduces exercise capacity in the heat. Eur J Appl Physiol. 2013
- Bjork JM, Grant SJ, Chen G, Hommer DW. Dietary tyrosine/phenylalanine depletion effects on behavioral and brain signatures of human motivational processing. Neuropsychopharmacology. 2014
- Linssen AM, Riedel WJ, Sambeth A. Effects of tyrosine/phenylalanine depletion on electrophysiological correlates of memory in healthy volunteers. J Psychopharmacol. 2011
- Ramdani C, Carbonnell L, Vidal F, BÃ©ranger C, Dagher A, Hasbroucq T. Dopamine precursors depletion impairs impulse control in healthy volunteers. Psychopharmacology (Berl). 2015
- ten Hoedt AE, de Sonneville LM, Francois B, ter Horst NM, Janssen MC, Rubio-Gozalbo ME, Wijburg FA, Hollak CE, Bosch AM. High phenylalanine levels directly affect mood and sustained attention in adults with phenylketonuria: a randomised, double-blind, placebo-controlled, crossover trial. J Inherit Metab Dis. 2011
- Opladen T, Okun JG, Burgard P, Blau N, Hoffmann GF. Phenylalanine loading in pediatric patients with dopa-responsive dystonia: revised test protocol and pediatric cutoff values. J Inherit Metab Dis. 2010
- Sano H, Murakami S, Sasaki S, Al-Mamun M. Effects of dietary energy intake and cold exposure on kinetics of plasma phenylalanine, tyrosine and protein synthesis in sheep. Arch Anim Nutr. 2010
- Kravitz HM, Sabelli HC, Fawcett J. Dietary supplements of phenylalanine and other amino acid precursors of brain neuroamines in the treatment of depressive disorders. J Am Osteopath Assoc. 1984
- Moats RA, Moseley KD, Koch R, Nelson M Jr. Brain phenylalanine concentrations in phenylketonuria: research and treatment of adults. Pediatrics. 2003
- Hardman CA, Herbert VM, Brunstrom JM, MunafÃ² MR, Rogers PJ. Dopamine and food reward: effects of acute tyrosine/phenylalanine depletion on appetite. Physiol Behav. 2012
- Okusaga O, Muravitskaja O, Fuchs D, Ashraf A, Hinman S, Giegling I, Hartmann AM, Konte B, Friedl M, Schiffman J, Hong E, Reeves G, Groer M, Dantzer R, Rujescu D, Postolache TT. Elevated levels of plasma phenylalanine in schizophrenia: a guanosine triphosphate cyclohydrolase-1 metabolic pathway abnormality? PLoS One. 2014
- Wissmann P, Geisler S, Leblhuber F, Fuchs D. Immune activation in patients with Alzheimer's disease is associated with high serum phenylalanine concentrations. J Neurol Sci. 2013
- Akimitsu O, Wada K, Noji T, Taniwaki N, Krejci M, Nakade M, Takeuchi H, Harada T. The relationship between consumption of tyrosine and phenylalanine as precursors of catecholamine at breakfast and the circadian typology and mental health in Japanese infants aged 2 to 5 years. J Physiol Anthropol. 2013
- Vrshek-Schallhorn S, Wahlstrom D, White T, Luciana M. The effect of acute tyrosine phenylalanine depletion on emotion-based decision-making in healthy adults. Pharmacol Biochem Behav. 2013
- JukiÄ‡ T, Rojc B, Boben-Bardutzky D, Hafner M, Ihan A. The use of a food supplementation with D-phenylalanine, L-glutamine and L-5-hydroxytriptophan in the alleviation of alcohol withdrawal symptoms. Coll Antropol. 2011
- Hildebrand P, KÃ¶nigschulte W, Gaber TJ, Bubenzer-Busch S, Helmbold K, Biskup CS, Langen KJ, Fink GR, Zepf FD. Effects of dietary tryptophan and phenylalanine-tyrosine depletion on phasic alertness in healthy adults - A pilot study. Food Nutr Res. 2015
- Kapatos G, Zigmond M. Dopamine biosynthesis from L-tyrosine and L-phenylalanine in rat brain synaptosomes: preferential use of newly accumulated precursors. J Neurochem. 1977