L-tyrosine is an amino acid that’s often used in supplements to improve cognitive function affected by stress.
Supplements containing L-tyrosine supplements may also help treatphenylketonuria(PKU).
Your body uses L-tyrosine (also known as tyrosine) to produce dopamine and norepinephrine.
Getty Images / Olena Ruban
These neurohormones (catecholamines) are quickly depleted when you’re under stress.
Though L-tyrosine supplements may restore them to healthy levels, they’re not safe for everyone.
Consult your healthcare provider before taking them.
Getty Images / Olena Ruban
Uses
L-tyrosine is made in the body from another amino acid calledphenylalanine.
Then, your body uses tyrosine to make three catecholamines:dopamine,norepinephrine, andepinephrine.
Periods of prolonged or severe stress often deplete these essential substances.
Both cognitive problems were brought on by situational stress, such as intense mental work or extreme weather.
However, this was primarily seen in short-term stressful situations or cognitively demanding scenarios.
Phenylketonuria
Phenylketonuriais an inherited disorder in which the person cannot process phenylalanine appropriately.
Since phenylalanine converts to L-tyrosine, this could lead to low levels.
Three studies evaluated the effect of taking L-tyrosine instead of or together with alow-phenylalanine diet.
In people with PKU, L-tyrosine blood levels significantly increased when taking supplements.
Tyrosine supplements should not be used in place of a low phenylalanine diet or medications to help manage PKU.
ADHD: L-tyrosine may improve some symptoms of ADHD through its role in the production of dopamine.
However, scientific studies supporting a direct link between L-tyrosine supplements and ADHD have yet to be completed.
Additionally, researchers found that 83 children (aged 6-13) with ADHD did not have deficiencies in L-tyrosine.
Depression:Depression is linked with imbalanced neurotransmitters like serotonin and dopamine.
L-tyrosine supplements may improve your mental health by boosting neurotransmitter levels.
Studies in lab animals suggest L-tyrosine may improve depression, but more research is needed in people.
Anxiety:A 2019 study suggests that L-tyrosine may reduce the brains fear response.
Though fear is closely related to anxiety, L-tyrosine’s direct role in anxiety hasnt been studied.
More research is needed to determine if supplements containing L-tyrosine can reduce anxiety.
Side Effects
L-tyrosine is generally recognized as safe (GRAS) by the FDA.
However, as a supplement, the safety of high doses and long-term use remains unknown.
Some have reported nausea, fatigue, and headaches with L-tyrosine supplementation.
Precautions
There is insufficient data on the safety of supplementing L-tyrosine in pregnant or breastfeeding people.
Therefore, sticking to food sources is the safest.
L-tyrosine can also trigger migraine headaches.
Avoid taking supplements if you struggle with migraines.
Most people get enough from their diet unless they’re following a low-protein meal plan.
For adults, the estimated amino acid requirement for phenylalanine and tyrosine combined is 14 mg/kg body weight daily.
The conversion rate of NALT to tyrosine is lower so you may need higher doses of NALT.
Dosage for Supplements
Dosage varies depending on what you’re taking it for and your L-tyrosine levels.
There is not a lot of data on the effects of high doses of L-tyrosine or toxicity.
The possible ill effects of such high doses over the long term are not known.
As a result, some supplement products may not contain the ingredients listed on the label.
Summary
L-tyrosine is a nonessential amino acid that is produced in the body.
It is also easily available in many of the foods we eat.
For this reason, a food-first approach to getting more L-tyrosine is usually preferred.
Speak with a healthcare provider if you are interested in using supplements of any sort.
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