L-Tyrosine boosts your mood, working memory, and cognition.

Especially in stressful situations.

See, Tyrosine replenishes your catecholamine neurotransmitters, including dopamine, norepinephrine, and epinephrine.

All of these get depleted when you’re under stress.

By restoring these brain chemicals, Tyrosine helps you maintain cognitive performance under pressure.

This includes cold water immersion, intense exercise, loud noise over 90 decibels, and sleep deprivation.

Overall, L-Tyrosine is highly effective at:

  • Reducing ADHD: Tyrosine can be of great help for battling ADHD symptoms, including lack of focus, irritability, and poor memory. It works very well with ADHD pharmaceuticals such as Adderall. ADHD drugs typically block the re-uptake of dopamine, but if there’s not enough dopamine available, these drugs are inefficient. That’s where L-Tyrosine helps, by boosting levels of the available dopamine in the brain.
  • Keeping your brain sharp under stress: Stress robs your brain of energy. It depletes the brain’s neurotransmitters, including dopamine, epinephrine, and norepinephrine. Low levels of these neurotransmitters lead to poor memory, focus, and mood. L-Tyrosine replenishes your neurotransmitters to maintain peak brain performance. (1)
  • Elevating mood and productivity: L-Tyrosine is a key building block for adrenaline, noradrenaline, and dopamine. With higher dopamine levels, your focus, productivity, mood, and mental clarity will improve.

What is L-Tyrosine

L-Tyrosine is a non-essential amino acid.

Amino acids are building blocks of protein. And besides helping you to build muscle, amino acids such as L-Tyrosine also serve as building blocks for your neurotransmitters:

  • Dopamine
  • Epinephrine (Adrenaline)
  • Norepinephrine (Noradrenaline)

These three are commonly referred to as “catecholamine” neurotransmitters.

As a nootropic, Tyrosine will improve certain parts of your prefrontal cortex linked to memory, flow states, creativity, executive function, and self-control.

In addition, L-Tyrosine helps with the production of certain thyroid hormones. Which are essential for both cognitive and physical health.

Foods that contain Tyrosine include fish, nuts, avocados, dairy, bananas, and turkey.

How it Works

Tyrosine improves your mood and cognitive performance in two main ways:

#1 Increases Neurotransmitter Levels

As a nootropic, Tyrosine converts into L-DOPA, which is used to build dopamine in the brain.

  • Dopamine is critical for both your physical and mental health. It helps control physical movements and plays a key role in attention, mood, memory, and logic.

Your brain converts the unused dopamine into noradrenaline and adrenaline. The other two catecholamine neurotransmitters.

Adrenaline, or epinephrine, is your main “flight-or-fight” response hormone. It’s what makes you act in emergent, stressful, or dangerous situations.

Noradrenaline, or norepinephrine, regulates your learning, emotions, attention, and sleep.

#2 Improves Mental Performance Under Stress

More often than not, stress negatively affects your ability to think clearly.

Any kind of stress can do this: from extreme sports, cold showers, exams, to arguing with your friend.

When you’re stressed, your brain quickly runs out of catecholamines.

A disbalance in these brain chemicals can lead to even more stress in the body. This is vicious cycle which leads to poor mental performance.

A study from the UK tested if L-Tyrosine can help combat the negative effects of stress.

The researchers measured cognitive performance in 8 soccer players. These players did a 90-minute soccer simulation task in a high-heat chamber to stimulate a high-stress environment.

Before exercise, these soccer players received either a Tyrosine pill or a placebo.

The study found that soccer players who supplemented with Tyrosine prior to high-stress exercise had a significantly higher cognitive and reaction time scores compared to the placebo group. (2)

The researchers found that when under high-heat conditions, the L-Tyrosine group were able to maintain peak cognitive performance despite the exposure to stressful conditions.

N-Acetyl L-Tyrosine vs. L-Tyrosine: Which One is Better?

N-Acetyl L-Tyrosine, also called NALT, is L-Tyrosine with the addition of an acetyl group.

In your kidneys, NALT converts back to L-Tyrosine.

Which in theory means that both L-Tyrosine and N-Acetyl L-Tyrosine have the same effects.

Some neurohackers report that NALT is more effective for them. Others say there’s no difference between the two.

Some research suggests that NALT is the less effective form of L-Tyrosine. Because it’s excreted in urine before your body can fully convert it to the active form – L-Tyrosine. (3)

Personally, I’ve found NALT and L-Tyrosine to be equally effective.

But it’s hard to say which one will work best for you. Because everyone’s body chemistry is different.

For this reason, I suggest trying both NALT and L-Tyrosine to see which gives you best results. This video done by the research team at Mind Lab Pro illustrates the comparison.

Effects of L-Tyrosine on the Brain

Part of the reason why stress negatively affects cognition is that it depletes your brain chemicals and Tyrosine that is used to synthesize them.

Low levels of dopamine and other catecholamines make your brain even more susceptible to the damaging effects of stress. This, in turn, drives your neurotransmitters in a downward spiral.

When your catecholamine levels are out of whack, all kinds of cognitive problems ensue. Including neurodegeneration and attention issues.

Supplementing with L-Tyrosine prior to stressful situations can easily counter this problem.

Research suggests that Tyrosine supplementation helps:

  • Improve learning and memory during cold exposure
  • Maintain peak cognition even when sleep deprived
  • Enhance brain performance during loud sound exposure (above 80 dB’s)
  • Support working memory during demanding cognitive tasks

Now, let’s proceed and look at which brain pathways Tyrosine affects:

Brain Cell Protection

In animal studies, L-Tyrosine is shown to protect the brain from the damaging effects of stress.

It does this by inhibiting the release of stress hormones such as cortisol. Along with supporting your brain chemicals to protect your neurons from free radical damage. (4)


Animal studies show that supplementing with Tyrosine prevents the depletion of dopamine, epinephrine, and norepinephrine that usually happens during stress.

L-Tyrosine also helps directly promote catecholamine production. Especially dopamine which your brain needs for mood, cognition, focus, and memory. (5)

Clinical Evidence of L-Tyrosine’s Benefits

Tyrosine Helps You Adapt to Novel Situations

L-Tyrosine will improve your cognitive flexibility.

In other words, it will help your brain adapt to new stimuli, environments, and situations.

New situations are often stressful, and they deplete your brain of resources. They also cause stress in the form of cortisol.

But L-Tyrosine helps counter this by replenishing your catecholamine brain chemicals.

The researchers measured these people’s cognitive flexibility by assigning them a task switching procedure.

The result?

People that took L-Tyrosine prior to the test had higher scores in terms of cognitive flexibility.

By contrast, the placebo group had no improvements.

The study concluded that L-Tyrosine helps supports cognitive flexibility by replenishing mental resources. (6)

Tyrosine Reduces ADHD

The efficacy of Tyrosine for ADHD is clearly supported by clinical evidence. As we’ll show you in a minute.

However, a number of users report building a tolerance to L-Tyrosine after a week or two of supplementing it.

One informal study from the 1980s supports this claim.

The study showed that L-Tyrosine provided a short-term reduction in ADHD symptoms. But over time, it lost is effects due to built-up tolerance.

This is something to keep in mind. Regardless if you’re suffering from ADHD or are in perfect cognitive health. By looking at anecdotal evidence, L-Tyrosine appears to affect each person differently.

However, peer-reviewed research shows that the positive effects of Tyrosine are long-term.

  • A 2011 study tested the effects of using amino-acid precursors to enhance dopamine and serotonin levels in the brain. 

The study used 5-HTP as the precursor for serotonin, and L-Tyrosine for dopamine.

The researchers recruited 85 young people between the ages of 4-18 for the trial. All of them had ADHD.

The trial lasted 8-10 weeks.

After 4 weeks, the participants gave their urinary samples so the researchers could measure their dopamine and serotonin levels.

If the levels weren’t adequate, the participants received higher doses of precursors until their ADHD symptoms reduced.

Ultimately, the study showed that Tyrosine and 5-HTP produced similar benefits to pharmaceutical ADHD drugs – and these benefits lasted. (7)

Tyrosine Maintains Healthy Blood Pressure Under Stress

Your blood pressure and cognitive function are very much interlinked.

When you’re under stress, your blood pressure goes up.

This brings about the inability to concentrate, focus, or think ahead.

How many times did you find yourself frozen when facing extreme stress, anxiety, or perhaps a panic attack?

The good news is, supplementing with L-Tyrosine can help you prevent rises in blood pressure during stress, along with helping you maintain your cognitive performance.

  • This study from Amsterdam looked into the task performance of volunteers after acute stress.

Now, acute stress can be anything.

From participating in an extreme sport, closing a business deal, having an argument, exercising, or hearing a loud noise. Which means this study is applicable to you, me, and everyone else who’s experienced stress in their lives.

Now, here’s the interesting thing: the participants in the study received L-Tyrosine 15 minutes prior to experiencing acute stress.

The study showed that people’s blood pressure reduced within 15 minutes after ingesting L-Tyrosine.

These results suggest that Tyrosine helps promote healthy blood pressure during stress. Which in turn, helps with the cognitive performance. (8)

L-Tyrosine Dosage

The optimal dosage of L-Tyrosine is 500-2,000mg per day.

As always, start with the lower end of the dosage to see how your body reacts.

You might get better results from taking smaller dosages. More isn’t always better.

Also, it’s important to take L-Tyrosine on an empty stomach. You should take it 2 hours after, or 1 hour prior to eating food. Otherwise, it won’t work.

If you’re curious why it wouldn’t work, it’s because Tyrosine competes for absorption with other amino acids in foods. Taking it alone allows Tyrosine to enter your system undisturbedly.

Side note: Long-term supplementation with Tyrosine can lower your serotonin levels. Symptoms range from fatigue to anxiety and depression. The best way to counter this is by taking a low-dose serotonin precursor, such as 5-HTP (25-50mg daily).

Is L-Tyrosine Safe?

L-Tyrosine is shown to be safe and non-toxic. Most people won’t experience any side effects from taking it.

That said, there are several occasions where L-Tyrosine might produce side effects:

  • If taking doses higher than 2,000mg per day. In this case, Tyrosine can cause migraines.
  • People with hyperthyroidism should avoid Tyrosine since it can raise thyroid hormones.
  • If you’re taking MAO inhibitors. These enhance dopamine levels in the brain. Stacking them with L-Tyrosine can raise your dopamine levels too high. This can make your blood pressure shoot up, cause severe digestive issues and headaches, and induce anxiety episodes and panic attacks.

L-Tyrosine FAQ

Does L-Tyrosine make you sleepy? According to WebMD, L-Tyrosine won’t make you sleepy – it will in fact make you more alert and boost cognitive function. Therefore, supplementing with Tyrosine before bed may not be a great idea.

Can L-Tyrosine cause weight gain? It’s been shown that Tyrosine increases adrenaline and noradrenaline, hormones which speed up your metabolism. Therefore, Tyrosine shouldn’t cause weight gain; on the contrary, it can help you lose weight.

Is L-Tyrosine an appetite suppressant? In theory, yes, Tyrosine is an appetite suppressant because it increases epinephrine and norepinephrine, two hormones that can reduce hunger.

How long does it take for L-Tyrosine to work? The answer to this question depends on the individual, their metabolism, and other factors, such as when was the last time they ate. That said, research suggests it takes around 15 minutes for L-Tyrosine to work and show its first effects.


When ingested, L-Tyrosine converts to L-DOPA, which your brain then uses to create dopamine.

The unused dopamine is then used to synthesize other catecholamine neurotransmitters: epinephrine and norepinephrine.

L-Tyrosine will help boost your motivation, memory, focus, and cognitive performance. Especially if you’re often bombarded with stress.

See, Tyrosine is the most effective when you take it prior to a stressful situation.

Stress normally depletes your brain of catecholamine neurotransmitters, such as dopamine and epinephrine. Which are crucial for mood and cognition.

  • Tyrosine negates the effects of stress on your mental performance by replenishing these essential brain chemicals.

As a result, you maintain peak brain performance during any type of stress; be it an extreme sport, loud noise, an argument with your friend, or an intense gym workout.

Overall, Tyrosine is a safe and well-tolerated nootropic which can help you:

  • Boost memory
  • Reduce ADHD symptoms (lack of focus, irritability, poor concentration)
  • Improve Mood
  • Enhance motivation to get things done

That said, if you take MAO inhibitors, or have a hyperthyroid condition, talk with your doctor before taking L-Tyrosine.


  1. Behavioral and cognitive effects of tyrosine intake in healthy human adults. (source)
  2. Effect of tyrosine ingestion on cognitive and physical performance utilizing an intermittent soccer performance test (iSPT) in a warm environment. (source)
  3. N-acetyl-L-tyrosine and N-acetyl-L-cysteine as tyrosine and cysteine precursors during intravenous infusion in humans. (source)
  4. Working memory reloaded: tyrosine repletes updating in the N-back task. (source)
  5. People are different: tyrosine's modulating effect on cognitive control in healthy humans may depend on individual differences related to dopamine function. (source)
  6. Tyrosine promotes cognitive flexibility: evidence from proactive vs. reactive control during task switching performance. (source)
  7. Treatment of attention deficit hyperactivity disorder with monoamine amino acid precursors and organic cation transporter assay interpretation. (source)
  8. Effect of tyrosine on cognitive function and blood pressure under stress. (source)

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