What is Tyrosine

Chemical Name: (S)-2-amino-3-(4-hydroxyphenyl)propanoic acid

Molecular Weight: 181.2

Structrual Formula:

Nitrogen Content: 7.73%

Tyrosine (13, 14)

  • L-Tyrosine is a non-essential (or semi-essential), neutral, genetically coded amino acid. It is very little soluble in water
  • Tyrosine synthesized in the body from phenylalanine
  • As a building block for several important brain chemicals, tyrosine is needed to make epinephrine, norepinephrine, serotonin, and dopamine, all of which work to regulate mood
  • Tyrosine also aids in the production of melanin (pigment responsible for hair and skin color) and in the function of organs in the body responsible for making and regulating hormones, including the adrenal, thryroid, and pituitary glands
  • Tyrosine is also involved in the synthesis of enkephalins, substances that have pain-relieving effects in the body
  • As tyrosine binds unstable molecules (called free radicals) that can potentially cause damage to the cells and tissues, it is considered as a mild antioxidant
  • Thus, tyrosine may be useful for people who have been exposed to harmful chemicals (such as from smoking) and radiation

Tyrosine and Stress (222)

  • Tyrosine acts as an adaptogen, helping the body adapt to and cope with the effects of physical or psychological stress by minimizing the symptoms brought on by stress
  • This is primarily due to the fact that tyrosine is a building block for norepinephine and epinephrine, the body’s two main stress-related hormones
  • Taken ahead of time, tyrosine allows some people to avoid typical bodily reactions and feelings from stressful situations like surgery, emotional upset, and sleep deprivation.

Tyrosine and Anxiety-related Hypertension (197, 198)

Tyrosine and Depression (23, 188, 189, 223, 224)

  • Tyrosine levels are occasionally low in depressed patients
  • A number of studies conducted in the 1970s showed encouraging results regarding the use of tyrosine to ease symptoms of depression, especially when used together with another supplement known as 5-hydroxytryptophan (5-HTP)
  • In one study from 1990, however, tyrosine failed to demonstrate any anti-depressant activity
  • More studies are needed in order to draw firm conclusions about the use of tyrosine to help treat mild to moderate depression

Tyrosine and Parkinson’s (225)

  • In the mid 1980s some researchers speculated that tyrosine may be useful for treating Parkinson’s
  • As Tyrosine can increase dopamine levels. (Diminished dopamine levels cause the symptoms of Parkinson’s disease)
  • However, this has never been proven and there is a question about how well oral tyrosine can get into the brain
  • Some medications for Parkinson’s currently under investigation that incorporate tyrosine along with other chemicals

Deficiencies in tyrosine (226)

Deficiencies in tyrosine would cause the following stmptoms:

  • Depression
  • Low blood pressure
  • Low body temperature
  • An under active thyroid

Tyrosine and Food (13)

Tyrosine can be found in:

  • soy products
  • Chicken
  • Turkey
  • Fish
  • Peanuts
  • Almonds
  • Avocados
  • Bananas
  • Milk
  • Cheese
  • Yogurt
  • Cottage cheese
  • Lima beans
  • Pumpkin seeds
  • Sesame seeds

Tyrosine and Cocaine addition

  • Cocaine addiction causes a deficiency of L-dopamine and causes both catecholamine and serotonin neurotransmitter imbalances
  • Administering both L-tyrosine and L-tryptophan can help increase these neurotransmitters
  • This regimen has been used in chemical dependency units, along with conventional therapies

Best used with Tyrosine (13)

If taking a tyrosine supplement it is best to take it at bedtime, or with a high carbohydrate meal to prevent competition of absorption with other amino acids. Folic acid, copper and vitamin B6 is a good combination to have with this nutrient to maximize absorption and effectiveness.

Precaution of Tyrosine (61)

  • Total amount of tyrosine taken in one day should never exceed 12,000 mg
  • Those who suffer from migraine headaches should avoid tyrosine, as it can trigger migraine headaches and gastrointestinal upset
  • Tyrosine should not be taken at the same time as levodopa, a medication used to treat Parkinson’s disease because levodopa may interfere with the absorption of Tyrosine


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