Tyrosine (N-Acetyl L-Tyrosine) is a non-essential amino acid that acts as a dopamine precursor and hence produces profound effects on memory and mental flexibility.
This amino acid is capable of enhancing many aspects of cognitive abilities, especially under stress. Several studies showed that military personnel and astronauts exposed to cold and altitude stressors were able to withstand these much better with increased tyrosine intake. Tyrosine has also been shown to increase concentration and attention as well as memory formation.
Other Common Names
N-Acetyl-L-Tyrosine, Tyrosine, L-Tyrosine, NALT.
Supports working memory, mental flexibility, and information processing
Supports adaptation to stressful circumstances
What Is Tyrosine?
Despite the reliance of nootropics enthusiasts on new synthetic research chemicals, often the most profound cognitive enhancing drugs are none other than amino acids and nutrients. Tyrosine is a non-essential amino acid, which is essential for the function of numerous cognitive features.
Tyrosine is most often used as a reliable dopamine precursor in addition to other brain chemicals like epinephrine and adrenaline . N-acetyl-L-tyrosine (NALT) is an acetylated form of the amino acid L-tyrosine. NALT (as well as L-tyrosine) is used as a nootropic because it acts as a precursor for the critical brain neurotransmitter dopamine. Dopamine has a significant role in brain activities linked to reward, motivation, and pleasure, and plays a crucial part in modulating focus, motivation, cognitive flexibility, and emotional resilience. In addition to these creative-productive capacities and states, dopamine is one of the primary regulators of motor control and coordination of body movements, so it is also essential for exercise and muscle performance. Supplying NALT (or other sources of L-tyrosine) for cognitive support may be especially useful when participating in more demanding or stressful tasks . Oral NALT has increased brain levels of L-tyrosine .
Tyrosine was found to enhance mental performance with greater benefits recorded as tasks progressed from easier (1-BACK) to more difficult (2-BACK) .
Marco’s Grounds Tyrosine Sourcing
N-acetyl-L-tyrosine (NALT) is an acetylated form of the amino acid L-tyrosine; it has better solubility in water, so it is a more functional form than L-tyrosine for use in liquids.
N of 1, i.e., individual response, subjective feedback in the community of users suggests that NALT is experienced somewhat differently, and often at much lower doses than the more commonly used L-tyrosine.
Marco’s Grounds uses a NALT that is sourced from family-owned organic farm and is non-GMO, gluten-free, and vegan.
Tyrosine Dosing Principles and Rationale
N-acetyl-l-tyrosine (NALT) seems to be experienced somewhat differently (and often at lower doses) than L-tyrosine. NALT is interesting because real-world experience of people taking it in the community of users does not match up with the bioavailability data. Marco’s Grounds believes it’s essential to consider bioavailability data, but not place too much weight on it. Especially, with ingredients like NALT, where almost all of the bioavailability studies have been either in animals, non-oral dosing (i.v, i.p. etc.), and usually both. During our formulation and testing process, the NALT form has been additive in the context of an overall formula at doses that are typically much lower than would be expected based on bioavailability data and research on L-tyrosine. We also believe that the supplementation of tyrosine, no matter which form is used, is subject to threshold responses (see Marco’s Grounds Dosing Principles). This is due to the tyrosine-induced increase in dopamine synthesis being regulated by end-product inhibition, i.e., once the optimal level is reached, higher levels of tyrosine will no longer increase dopamine synthesis) .
Tyrosine Key Mechanisms
Supports working memory [14–20]
Supports cognitive flexibility 
Supports logical reasoning 
Supports mathematical processing 
Supports convergent (“deep”) thinking—a component of creativity 
Supports perceptual-motor task performance [16,23]
Supports inhibition of behavioral responses—a cognitive control function 
Precursor for catecholamine synthesis (dopamine, noradrenaline, and adrenaline) 
Supports the rate of dopamine synthesis and release upon neuronal activation [6–11]
Supports norepinephrine synthesis and release upon neuronal activation [11–13]
Protects from neurotransmitter (DA, NE) depletion due to increased brain activity 
Protects from performance decline during cognitively demanding tasks 
Protects from the adverse effects of stress on cognitive performance [16–19,23]
Protects from adverse behavioral responses to environmental stress 
Protects from stress-induced decreases in norepinephrine levels 
Protects from stress-induced increases in blood pressure [16,23]
Supports global mood 
Citicoline, Mucuna Pruriens, Phenylalanine, Phenylethylamine, Hordenine, Phosphatidylserine, Rhodiola Rosea, Vitamin C
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