L-TYROSINE

L-Tyrosine is an amino acid naturally produced by the body and can be found in various foods such as cheese, chicken, turkey, fish, and more. It is known for its ability to help improve alertness, attention, and focus, but at higher doses also physical performance. These improvements are mostly observed when physically or mentally stressed (see the “How?” section below to learn why that is). This may include mentally challenging work, lack of sleep, physical exercise, and even cold environments. For example, when individuals with sleep deprivation supplemented with L-Tyrosine, they were able to focus on cognitive demanding tasks for 3 hours longer than those that didn’t supplement [14].

Cognitive flexibility is your ability to switch between tasks quickly. Have you every had a stack of tasks that needed to get done and you find yourself exhausted switching between them? Each time you switch between tasks, you incur a cost to switch your thinking & attention. L-Tyrosine supplementation helps reduce this cost making it easier to handle multi-tasking [13].

L-Tyrosine has been extensively studied for short-term stressful situations, but there’s also research showing significant mood improvement when supplemented during a long-term stressful environment [1]. A fascinating study on individuals in the Antarctic tested the effect of L-Tyrosine supplementation on mood during the winter (~138 days), which is a major stressor due to the cold environment. They found mood ratings increased by 47% when supplementing with L-Tyrosine and decreased by 136% without [1].

How?

Have you ever given a presentation or been put on the spot and suddenly forget everything? Or maybe you crammed for a test all night and have trouble remembering everything from a lack of sleep? When we’re placed in stressful conditions or working on cognitive demanding tasks, our catecholamines dopamine and norepinephrine can quickly deplete and result in cognitive decline [4]. These catecholamines play a vital role in working memory and attention [2]. L-Tyrosine easily passes the blood-brain barrier to produce more of these catecholamines when needed to reverse the stress-induced cognitive decline. Interestingly, it seems this production exclusively happens for active neurons [3], meaning your current cognitive tasks & memory recall are likely prioritized.

The transporter used by L-Tyrosine to pass the blood-brain barrier is shared with other amino acids [4]. It’s not required to be fasted to get the benefits of this supplement, but this research indicates you may have a higher percent of your dosage utilized in the brain if taken while fasted due to no competition for using the transporter from any other amino acids.

Many brands use N-Acetyl L-Tyrosine (NAT) because it’s cheaper, but it’s far less effective. Regular L-Tyrosine raises blood levels by 130%-276% [9, 10, 11, 12] depending on the dosage and method, while NAT only provides a 0-25% increase [6, 7]. Worse yet, up to 60% of NAT is flushed out without any benefit [7, 8]! A research study concluded that the usefulness of NAT as a means for increasing your levels of L-Tyrosine was “not apparent” [6].

Dosage

L-Tyrosine is typically taken as 500-2000 mg before experiencing a stressor (like cognitive demanding tasks, exercise, a presentation, or cold weather). However, taken in excess can cause irritability or headaches in some. High doses can also cause gastrointestinal distress, but can be alleviated by splitting it up into two half-doses taken 30 minutes apart from each other.

It takes about 1-2 hours after ingestion for it to hit peak levels, afterwards it lasts up to 8 hours [9].

As with all ingredients, ANOO aims to provide the optimal effective dosage based on the latest research. At the same time we also don’t unnecessarily increase dosages since that can increase the chance of side effects. Fewer premium ingredients dosed at their most researched amounts is not only a lot safer, but also more likely to give you your intended result.

Benefits

• Improved working memory during stressors [5, 15, 16]
• Improved cognitive performance during stressors [4, 15, 16]
• Improved cognitive flexibility (task switching) [13]
• Stay focused for longer [14]
• Improved mood during stressor [1, 15]

References

[1] https://pubmed.ncbi.nlm.nih.gov/18274206/
[2] https://pubmed.ncbi.nlm.nih.gov/26790349/
[3] https://pubmed.ncbi.nlm.nih.gov/17513421/
[4] https://pubmed.ncbi.nlm.nih.gov/26424423/
[5] https://pubmed.ncbi.nlm.nih.gov/24379768/
[6] https://pubmed.ncbi.nlm.nih.gov/2507878/
[7] https://pubmed.ncbi.nlm.nih.gov/1996632/
[8] https://pubmed.ncbi.nlm.nih.gov/14621123/
[9] https://pubmed.ncbi.nlm.nih.gov/481129/
[10] https://pubmed.ncbi.nlm.nih.gov/9579151/
[11] https://pubmed.ncbi.nlm.nih.gov/8523192/
[12] https://pubmed.ncbi.nlm.nih.gov/2463918/
[13] https://pubmed.ncbi.nlm.nih.gov/25598314/
[14] https://pubmed.ncbi.nlm.nih.gov/7794222/
[15] https://pubmed.ncbi.nlm.nih.gov/17585971/
[16] https://pubmed.ncbi.nlm.nih.gov/25797188/