Tyrosine is an amino acid, (a building block of proteins) that itself is converted from another amino acid, Phenylalanine, in the body and can be found in the diet in higher doses in dairy products, meats, fish, eggs nuts and beans.
Tyrosine has a stimulatory effect on the brain and body and is metabolised to produce the likes of dopamine and adrenaline. Forms of Tyrosine are supplemented in sports and functional nutrition for Energy, Cognitive Performance, Fat Loss, Libido, Stress Reduction and Mood Improvement. Whilst is commonly taken to treat Depression, ADD, ADHD, Narcolepsy, Parkinsons, Chronic Fatigue and a plethora of other disorders.
The two most common types of Tyrosine found in nature and in supplementation are L-Tyrosine and N-Acetyl L-Tyrosine (NALT).
NALT is a form of L-Tyrosine and while it appears L-Tyrosine and NALT trigger the same outcomes in the body once absorbed, the addition of the acetyl group in NALT means that NALT is water-soluble and is thought to cross the blood-brain barrier more efficiently than L-Tyrosine.
- Tyrosine appears to effectively improve cognition during acute stressors (altitude and cold being tested most)- https://www.ncbi.nlm.nih.gov/pubmed/2736402
- Perceptions of stress during acute stressors, as well as related symptoms of acute stress, appear to be reduced following tyrosine ingestion - https://www.ncbi.nlm.nih.gov/pubmed/10230711
- There appears to be an increase in subjective well being during stress when tyrosine is preloaded
- It appears to preserve working memory during acute stressors - https://www.ncbi.nlm.nih.gov/pubmed/8029265
Clinical studies and research have indicated that Tyrosine can be consumed in amounts up to 12 grams per day. However, a typical serving in a functional supplement will be in the region of 200-500mg.
Tyrosine is often combined with Carnitine due to their perceived synergistic effects. Acetyl L-Carnitine has serotonergic and cholinergic effects whilst L-Tyrosine has dopaminergic effects.
N-Acetyl L-Tyrosine is an active ingredient in Vi-Brain Nootropic Supplement.