Tyrosine
Also known as L-tyrosine
Tyrosine is a conditionally essential amino acid the body makes from phenylalanine. It is the raw material for dopamine, norepinephrine, and adrenaline, as well as thyroid hormones and the pigment melanin.
Why it matters
What it does in your body
- Precursor to dopamine, norepinephrine, and adrenaline
- Building block of thyroid hormones
- Precursor to melanin (skin and hair pigment)
- Building block of protein
Intake guidance
How much you need
There is no separate requirement, because the body makes tyrosine from the essential amino acid phenylalanine, and both are counted together as the aromatic amino acids. It becomes conditionally essential in people with PKU, who cannot make it from phenylalanine.
What affects it
What affects your intake
Phenylalanine supply
The body converts phenylalanine into tyrosine, so adequate phenylalanine covers tyrosine for most people.
PKU
People with phenylketonuria cannot make tyrosine normally, so it becomes essential and is added to their medical diet.
Stress and stimulation
Because it feeds stress-response neurotransmitters, tyrosine is studied for demanding, sleep-deprived conditions.
In practice
Good to know
Good to know: tyrosine supplements are marketed to sharpen focus and stress resilience, and the evidence suggests they may help maintain mental performance during acute stress or sleep loss, but not in everyday rested conditions. Because tyrosine feeds dopamine and adrenaline, it is a target of interest for mood and attention, though food supplies plenty for normal needs.
Where to get it
Best food sources
The bottom line
Tyrosine is made from phenylalanine and comes from protein foods, so healthy people get enough. Supplements mainly help under acute stress or sleep deprivation.
Track tyrosine automatically
Tyrosine is one of the 92 nutrients Vora reads from a photo of your meal, so you can see where you stand without weighing or logging by hand.
Sources and method
The classification, roles, and guidance on this page come from the references below, drawing on the Institute of Medicine (now the National Academies) Dietary Reference Intakes and reputable nutrition science.
- Institute of Medicine (2005), Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids
- National Library of Medicine, MedlinePlus
This page is for general education, not medical advice. Reference intakes are population averages for healthy people and do not replace guidance from your doctor or a registered dietitian, especially if you are pregnant, managing a health condition, or considering supplements.