Tyrosine is one of the amino acids, which are the building blocks of protein. The body makes tyrosine from another amino acid called phenylalanine. Tyrosine can also be found in dairy products, meats, fish, eggs, nuts, beans, oats, and wheat.
Supporting research & information
Tyrosine is used in protein supplements to treat an inherited disorder called phenylketonuria (PKU). People who have this problem can't process phenylalanine properly, so as a result they can't make tyrosine. To meet their bodies' needs, supplemental tyrosine is given.
People take tyrosine for depression, attention deficit disorder (ADD), attention deficit-hyperactivity disorder (ADHD), the inability to stay awake (narcolepsy), and improving alertness following sleep deprivation. It is also used for stress, premenstrual syndrome (PMS), Parkinson's disease, Alzheimer's disease, chronic fatigue syndrome (CFS), alcohol and cocaine withdrawal, heart disease and stroke, ED (erectile dysfunction), loss of interest in sex, schizophrenia, and as a suntan agent and appetite suppressant.
Some people also apply tyrosine to the skin to reduce age-related wrinkles.
Heathline: Tyrosine is a popular dietary supplement used to improve alertness, attention and focus.
It produces important brain chemicals that help nerve cells communicate and may even regulate mood.
Despite these benefits, supplementing with tyrosine can have side effects and interact with medications. Tyrosine is an amino acid that is naturally produced in the body from another amino acid called phenylalanine.
It’s found in many foods, especially in cheese, where it was first discovered. In fact, “tyros” means “cheese” in Greek.
It is also found in chicken, turkey, fish, dairy products and most other high-protein foods.
Tyrosine helps make several important substances, including :
Dopamine: Dopamine regulates your reward and pleasure centers. This important brain chemical is also important for memory and motor skills.
Adrenaline and noradrenaline: These hormones are responsible for the fight-or-flight response to stressful situations. They prepare the body to “fight” or “flee” from a perceived attack or harm.
Thyroid hormones: Thyroid hormones are produced by the thyroid gland and primarily responsible for regulating metabolism.
Melanin: This pigment gives your skin, hair and eyes their color. Dark-skinned people have more melanin in their skin than light-skinned people.
It’s also available as a dietary supplement. You can purchase it alone or blended with other ingredients, such as in a pre-workout supplement.
Supplementing with tyrosine is thought to increase levels of the neurotransmitters dopamine, adrenaline and norepinephrine.
By increasing these neurotransmitters, it may help improve memory and performance in stressful situations.
SUMMARY: Tyrosine is an amino acid that the body produces from phenylalanine. Supplementing with it is thought to increase important brain chemicals, which affect your mood and stress response.
Studies show that tyrosine can help maintain your mental capacity when taken before a stressful activity. However, there is no evidence that supplementing with it can improve your memory. Tyrosine is “generally recognized as safe” (GRAS) by the Food and Drug Administration.
It has been supplemented safely at a dose of 68 mg per pound (150 mg per kg) of body weight per day for up to three months.
The Bottom Line
Tyrosine is a popular dietary supplement used for a variety of reasons.
In the body, it’s used to make neurotransmitters, which tend to decrease under periods of stressful or mentally demanding situations.
There is good evidence that supplementing with tyrosine replenishes these important neurotransmitters and improves mental function, compared to a placebo.
Supplementing with it has been shown to be safe, even in high doses, but has the potential to interact with certain medications, warranting caution.
While tyrosine has many benefits, their significance remains unclear until more evidence is available.
In dopaminergic cells in the brain, tyrosine is converted to L-DOPA by the enzyme tyrosine hydroxylase (TH). TH is the rate-limiting enzyme involved in the synthesis of the neurotransmitter dopamine. Dopamine can then be converted into other catecholamines, such as norepinephrine (noradrenaline) and epinephrine (adrenaline). Tyrosine is a precursor to neurotransmitters and increases plasma neurotransmitter levels (particularly dopamine and norepinephrine (noradreniline), but has little if any effect on mood in normal subjects. The effect on mood is noted in humans subjected to stressful conditions (see below).
A number of studies have found tyrosine to be useful during conditions of stress, cold, fatigue, prolonged work and sleep deprivation, with reductions in stress hormone levels, reductions in stress-induced weight loss seen in animal trials, and improvements in cognitive and physical performance seen in human trials.
Tyrosine does not seem to have any significant effect on cognitive or physical performance in normal circumstances, but does help sustain working memory better during multitasking.
Thomas JR, Lockwood PA, Singh A, Deuster PA (1999). "Tyrosine improves working memory in a multitasking environment". Pharmacol. Biochem. Behav. 64 (3): 495–500. doi:10.1016/S0091-3057(99)00094-5. PMID 10548261.