Tyrosine Supplement Reference

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.

What is Tyrosine?

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


Tyrosine Sources

  • Meats: Chicken, fish, beef, and really any other form of meat has high levels of tyrosine, up to 1000mg per serving. 3
  • Eggs/Dairy: Eggs and anything dairy related contain decent amounts of tyrosine. Cheese in particular is a great source.3
  • Nuts/Seeds: Most nuts and seeds have natural tyrosine in them. 3
  • Supplementation: Usually sold in 1 gram capsules, or in preworkout powders.

Benefits of Supplementing Tyrosine

  • Cognitive Enhancer WHEN STRESSED: There are tons of studies on the effect of L-Tyrosine on overall cognition. Most studies conclude that tyrosine supplementation does not improve cognition in normal conditions.4 However, tyrosine can improve cognition in times of acute stress (acute physical or mental activity), and the research to back this claim is comprehensive.5678 Acute stress means something that is abnormally stressing - for example, being exposed to extreme cold, physical exhaustion, or severe sleep deprivation. The research shows that tyrosine supplementation before a major stressor allows for better working memory, faster cognition, and deeper thinking. The reasoning behind these results is that during times of acute stress the body demands more dopamine, norepinephrine, and epinephrine, which takes more tyrosine to generate.

Downsides and Safety to Tyrosine Supplementation

There are several known safety issues with tyrosine supplementation.

  • May Increase Skin Cancer Rates: Tyrosine is a key amino acid in the development of melanin, which is skin pigment. Increased melanin production leads to higher incidences of skin cancer generally. There is no causal evidence linking L-Tyrosine supplementation to higher rates of skin cancer, but this is not a well studied topic.
  • Interacts With Thyroid Medication: Tyrosine is also a key precursor for thyroid hormones in the body. L-Tyrosine supplementation may increase thyroid hormone production slightly, which can throw off patients being treated for hypo/hyperthyroidism.
  • May Increase Blood Lipids: Mice treated with L-Tyrosine showed signs of elevated cholesterol and triglycerides. There have been no studies examining this in humans.9
  • Increases Migraine Frequency: Tyrosine supplementation has been linked to higher occurrences of migraines. This mechanism is not well understood.10

Dosages and Timing For Tyrosine

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.

Conclusion and Recommendations

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.

Research / Sources