I’m a big advocate of science-backed supplements to optimize mental and physical performance. These articles represent my own distilled research on effectiveness, risk, and other things to consider before supplementing. To see what supplements I am currently taking, definitely check out the “My Current Supplements” article at the top of this section. Most of the sources are dervived from Examine.com, which is a great resource, but my intent is to distill it down and add my own research + anecdotes.
Tyrosine (also known as L-Tyrosine) is a non-essential amino acid that is found in pretty much any food that contains protein. It is the precursor compound to several neurotransmitters (namely: dopamine), thyroid hormones, and melanin (skin pigment). All three of these pathways are highly regulated by the body, which typically means having more precursor does not result in increases in any of those three functions. The big exception is due to dietary deficiency and stress, whereby tyrosine has shown to be somewhat effective as a supplement. Dietary deficiency is extremely rare due to how plentiful it is in almost all diets.1
L-Tyrosine is a pretty common supplement due to being included in most preworkout powders, but is also popular among the nootropics community as well. As you’ll find in my writeup below, I don’t believe that regular L-Tyrosine supplementation is effective, and may even cause health issues long term.
The below diagram from Wikipedia shows the pathways that tyrosine touches from a neurotransmitter perspective.2
There are several known safety issues with tyrosine supplementation.
L-Tyrosine should be taken in the morning, usually in the 1 gram to 2 gram dosing range.
Supplementation should only occur an hour or two before an acute stressor for maximum effectiveness. Intense physical exercise, mental demands, or other acute stressors would qualify. It can also promote wakefulness when combined with caffeine.
I do not recommend taking L-Tyrosine every day.
L-Tyrosine is at best a good cognitive enhancer in stressful situations, but at worst may be unsafe to take regularly. The benefits of daily supplementation are not worth the cost or risk associated with the supplement, so I would recommend supplementing only when required.
L-Tyrosine is relatively expensive at $0.27 per dose (assuming 1.5g) when buying from a brand like Doctor’s Best.