Stressed Out? L-Tyrosine Can Help You Feel Better and Get More Done

L-tyrosine is an amino acid (the building block of a protein) with some pretty cool benefits for your brain, focus, stress management and more. Getting plenty of tyrosine, either through diet or from a supplement, can make a major difference in your brain function. Keep reading to learn how it works, how to take it and all the bonuses it offers.

How tyrosine works

Tyrosine is essential when you’re under stress or need to power through something requiring a lot of focused attention. If you run out, you might start to feel like you’ve hit a mental wall. That’s because tyrosine is a precursor to some of the most important neurotransmitters in your brain. Without tyrosine, your body can’t make:^[1]

• Dopamine for mood and motivation
• Norepinephrine for muscle recovery and blood flow
• Adrenaline for focus and drive

When you’re under physical or mental stress, your neurotransmitter bank account can start to run low. But if you have plenty of tyrosine in your bloodstream, that extra stash will replenish the neurotransmitters before stress can deplete them, allowing you to stay sharp for longer without getting burned out.^[2]

And because tyrosine is a building block for so many major brain chemicals, it benefits you in a lot of different ways. Let’s take a look at the main benefits of tyrosine, and how you can make sure your brain gets plenty of it.

L-tyrosine benefits for stress, mood and more

Relieves stress and helps you focus

Stress depletes your brain’s norepinephrine stores, and when norepinephrine runs low, your memory, focus, and general cognition all suffer.

If you’re dealing with a lot of stress, tyrosine can help. Tyrosine keeps your brain performing at its best during stress and improves your focus with tasks that demand mental endurance.^[3] In this way, tyrosine is a nootropic — it helps your brain tackle challenges, without getting burned out.

Related: If you’re feeling overwhelmed, check out these self-care tips to bounce back when life has you down.

May improve mood

If you’re feeling blue, tyrosine may be able to help. That’s because tyrosine turns into dopamine, a central neurotransmitter that controls pleasure and motivation. Dopamine also influences serotonin, and together, the two are thought to play a central role in regulating your mood.^[4]

A 2016 rodent study found that tyrosine is involved in the body’s stress response and restores normal levels of noradrenaline (norepinephrine) in the brain.^[5] However, other research suggests that tyrosine does not have an effect on mood disorders like depression.^[6]

That said, there aren’t any notable risks or side effects to taking tyrosine. If managing stress helps boost your mood, give it a try.

Should you take tyrosine for your thyroid?

Tyrosine is also a precursor to levothyroxine, a thyroid hormone that’s low in people with hypothyroidism or Hashimoto’s thyroiditis. It seems reasonable to think that tyrosine would be great for you if you have an underactive thyroid, but that might not be true.

In mice, tyrosine replenished thyroid hormones that were low due to stress.^[7] But in humans, there’s no evidence that tyrosine improves thyroid function. In fact, some hormone doctors report that patients who take tyrosine see a further decrease in thyroid function. In theory, that could happen because tyrosine boosts norepinephrine, which regulates thyroid hormones and is already often too high in people with hypothyroidism.^[8]

If you have concerns, talk to your doctor before taking tyrosine.

How to use tyrosine supplements

You can get tyrosine from foods like chicken, turkey, fish and cheese, but if you want the cognitive benefits of tyrosine, you’re better off taking a supplement.

Purified tyrosine gets pushed directly to neurotransmitter synthesis, while tyrosine in food ends up going to your muscles, along with all the rest of the amino acids you eat.^[9]

Fortunately, tyrosine supplements are inexpensive and very effective.

Tyrosine side effects

Tyrosine supplements are quite safe. There are no major reported side effects of tyrosine, even when people took it three times a day at higher doses.^[10]

• Does tyrosine give you energy? Yes, but it comes in the form of endurance. It might not make you feel like jumping up and going for a long run, but if you’re doing a 5k, it could help you push yourself to beat your personal best. A study of eight cyclists riding in the heat found that tyrosine gave the participants a boost of endurance that helped them go further before they bonked.^[11]
• Does tyrosine make you sleepy? It may help with fatigue. One study found that when comparing levels of tyrosine in patients, those with lower levels overall felt more fatigue than those with elevated tyrosine. Those with increased tyrosine levels also felt they had a higher quality of life.^[12] That said, some people say tyrosine can make them sleepy. Keep reading to learn about how much tyrosine to take and how to experiment with your dosage.

Tyrosine dosage and sourcing

• What type of tyrosine should I buy? You can get tyrosine on its own, or in special blends designed to amplify its brain-boosting effects. Bulletproof Smart Mode contains a patent-pending blend of ingredients, including tyrosine, rosemary and artichoke leaf extract.
• How much should I take? Take one serving of Smart Mode in the morning or whenever you need a mental boost.
• When should I take tyrosine? Some sources suggest taking it first thing in the morning with a breakfast of complex carbohydrates and protein. But you can take tyrosine anytime you need it, especially if you’re stressed.

This is an updated version of an article originally published October 2018.