L Tyrosine Benefits Side Effects

Spread the love


L-Tyrosine is a naturally occurring amino acid with a lot of terrific benefits for our brains, stress, and mood and is the precursor for dopamine, adrenaline, and norepinephrine. [1]  These neurotransmitters are three of the most important we have.  Today is all about L Tyrosine Benefits and Side Effects.

Dopamine is involved in pleasure and reward and in playing an important roll in our mood and motivation.  Adrenaline is our drive and focus, and norepinephrine muscle recovery and blood flow. l tyrosine benefits side effects

 These last two together modulate our blood pressure, heart rate and even blood sugar.

Our body produces L-Tyrosine from another amino acid called L-Phenylalanine and you can find L-Tyrosine in foods like dairy products, fish meat, eggs, and dairy.  Since our body does produce it in proper amounts taking it as a supplement isn’t really necessary for our normal basic health.

There is research that says taking L-tyrosine as a supplement can increase our energy, boost our mood, enhance cognition, and increase our motivation.  Because we don’t need this amino acid in extra amounts when at a normal healthy state, it is more beneficial when we are under either physical or environmental stress.

One study found that military personnel who were exposed to cold and altitude stressors were able to withstand these much better after taking L-tyrosine [2].

Another study found a reduction in blood pressure along with preservation of the cognitive ability of military while engaged in combat training.[3]

l tyrosine benefits side effects

Benefits of L-tyrosine


Mental Sharpness and Sleep Deprivation

A study on the effectiveness of L-tyrosine on lack was conducted.  Participants were given L-tyrosine during an all-nighter where they had to stay awake all night.  The participants stayed awake for a total of 24 hours with no sleep.  Mental tests and mood tests were conducted throughout the study.  Halfway into the test, half of the participants were given tyrosine and the other half were given a placebo.  The result of the study was that those given tyrosine were able to maintain their brain power while those taking the placebo were not. [4]

A single dose of it helped people who lost a night’s sleep stay alert for three hours longer than they otherwise would (5).

Cognitive Enhancement Under Stress

L-Tyrosine has been studied over again for many years now and has shown I can significantly boost our cognition while under stressful conditions.  It basically offsets the expected deficits caused by environmental stress situations in the working memory and processing of information.

There was a small study done where military cadets who were doing combat training were given a protein drink that contained tyrosine 5 times/day.  Others were given the same protein drink with a placebo.  The participants were tested before being administered the tyrosine and then six days following taking the tyrosine.  What was found was that tyrosine was linked to better performance on memory and tracking tests and reduced the effects of stress and fatigue on their mental performance.  Those who took the protein drink containing the placebo showed no differences.

Cognitive Flexibility

Cognitive flexibility is described as the mental ability to switch between thinking about two different concepts and to think about multiple concepts simultaneously.

Our working memory plays a big part in our concentration and ability to follow instructions.

In a study of 22 women who were given tyrosine, the results showed that their working memory improved when during a mentally demanding task.  Not for those taking a placebo.[5]

Similarly, another study where 22 volunteers were given tyrosine or a placebo prior to completing a cognitive flexibility test.  Results showed that those who took tyrosine had an improvement in their cognitive flexibility. The group taking the placebo did not. [6]

If you thought that maybe l-tyrosine may help your physical performance, it does not as shown here. [7]

There is absolutely no research done to say taking tyrosine without being stressed can improve your mental performance.

Lastly, no research suggests that supplementing with tyrosine in the absence of a stressor can improve mental performance. In other words, it won’t increase your brainpower.


Working Memory

It does appear that L-tyrosine does boost our working memory as tasks become increasingly more challenging.  This is likely because the level of stress is amped up where L-tyrosine works.

In a study on adult volunteers engaged in a mental task that gets progressively challenging found the ones taking the tyrosine did much better on the more difficult levels, but not on the easier levels. [8]


L-Tyrosine to Treat Depression

Tyrosine has been shown to help certain people suffering from depression in a few clinical trials.  One placebo-controlled case involving only one subject, a 30-year-old woman suffering from depression.  It was observed that she showed significant improvement after being treated with L-tyrosine. [9]

Once she stopped the tyrosine treatment and began a placebo treatment her symptoms resumed.  When once again she was put on a tyrosine treatment her improvement returned. [10]

A larger clinical trial using 65 depression patients did not support that tyrosine can be used as an antidepressant [11].

L-tyrosine works because it is a precursor for dopamine, adrenaline, and norepinephrine.  However, we know that depression is caused by many things, not just a lack of dopamine or norepinephrine.  This may be why tyrosine has not been effective in all studies.


L Tyrosine A Treatment for ADHD

In young people with ADHD, it is not uncommon to find they lack proper levels of tyrosine.  Studies have been performed to see if supplementing with L-tyrosine could potentially be an adjunct treatment for ADHD.

In 2011 a study was performed on both pediatric and adults suffering from ADHD.  The treatment with L-tyrosine showed 77% of patients showed a significant improvement over a period of 10 weeks. [12]


Improving Mood During Winter Months

During stressful situations such as cold weather or elevated altitudes, an increase in tyrosine levels improved mood by lowering the intensities of symptoms from the cold and lowered oxygen levels [13].In a long-term study, patients in Antarctica were given tyrosine supplements daily over the summer and winter. However, during only stressful conditions in the winter months did the tyrosine supplements help to improve mood (by 47%) [14]. Summer conditions were not harsh enough to elicit a response [15].


Side Effects of Tyrosine

The com on side effects associated with l-tyrosine tend to be short, mild and appear as a headache, digestive upsets, gastrointestinal upset, and indigestion.

Do not take L-tyrosine if you are taking HTN (high blood pressure) medication, Levadopa, MAO inhibitors, thyroid meds, or stimulants.

Never take it if you have thyroid disease, melanoma, or Graves’ disease.

I always say unless otherwise stated these supplements should not be given to children or pregnant or nursing women.  Studies have not been done to sufficiently say otherwise.


Dose of L-tyrosine

Tyrosine supplements are around 500 to 1500 mg daily, in tablets and capsules

N-Acetyl-L-Tyrosine (NALT) is a stronger form, so dosage may be lower


To Wrap it Up

This amino acid has been studied extensively and there is plenty of evidence that does what it states it does.  These include enhancing our cognitive ability and of course maintain or improve our mental performance when put under acute stress either mental or physical.

Taking L-Tyrosine when you have a normal healthy brain will not improve anything for you.  However, it will under the conditions I have laid out above.

When you are under elevated stress, L-tyrosine can be your best friend and by all accounts, it does just that.

13 thoughts on “L Tyrosine Benefits Side Effects”

  1. Thanks for this most interesting article, Stew.  

    What it points up for me is that even though we do get enough amino acids (in the natural course of things) to keep our bodies running well, using the natural properties of these substances to boost and bolster our body systems when needed is very possible and apparently comes at a lower cost (less unpleasant side effects) than some other stuff meant to deal with the same problems.  

    This is fascinating.

  2. Anything with lots of health benefits I’m interested in and this is something I’ve not really heard of before. I especially like the thought of it boosting my mood during winter months! That’s definitely needed sometimes.

    Do you get enough of it from foods or would you recommend taking a supplement?? I never like taking supplements and try to get all nutrients from my food as much as possible.

    • We do get enough of it when healthy.  When stressed a lot because of being out in cold weather or just plain stressed, this is when it will help

  3. I am constantly working under very high pressure  and I have  been trying to find supplements that will lower amount of stress that comes with my line of work to honest  it’s not that easy that was antill ifound out  about nootropic  and the way I take manage to lower amount of stress that I go through since then I have really changed and I doing well with my nootropic.

  4. Hello Stew,This the information that i have been looking for a long time.  My work is consisting of loading, unloading, driving and talking to customers the whole day.  My work entails me to work 6 days a week.  I very stressful job indeed and i have been looking for my mental alertness and health.  Im glad that i have found this website.  I will surely make an order for my myself and recommend to other people who have stress related workload.Here in Canada the winter is very depressing and you have mentioned that L Tyrosine will help.Thank you for a great resource

  5. This article about L Tyrosine was very interesting to me for its effect on mental performance and memory recall support in times of stress. As I continue to age these facets of my health have deteriorated. In addition I have a condition brought on by low dopamine levels. This has also affected my mood, tending toward depression.

    However, you say that L Tyrosine should not be used when taking Levodopa which is what I am taking for my condition. What would happen if I took both?



    • If you took both together the L-tyrosine lower the effectiveness of the Levodopa.  Sources say you can take them 2 hours apart but for that, I would talk to your physician

  6. Hi, Stew.  I really liked your post on Tyrosine.  It brought up a question to my mind.  Have you found any information on if the amino acid can be used to improve mental function in the elderly?  I’m wondering if as we age our body’s ability to produce tyrosine naturally diminishes or not, and if an older person with degraded abilities to think and reason normally would benefit from taking the supplement.  Have you found any studies on that?  Thanks for the great post.


  7. This is interesting piece of article. Though I’m not conversant with health related discussion because it’s not my line, but with what I’ve just read about Mental awareness right here base given me some clue. Thanks to this wonderful writing But I need to the author to shed more light for me on this substance L-tyrosine. Ice only read the huge advantage the great product but what I haven’t been cleared about is the side effect or it disadvantage if it has any? Thumbs up to the writer. Thank you. Expecting your reply

    • Normally when we are stress-free and comfortable, we don’t need this, however, if we are going to be out in bad weather (cold) and stressed because of it, then it is beneficial.  If we are stressed out physically then it would be beneficial as well

Leave a Comment