Tyrosine

Background

Tyrosine, also known as L-tyrosine, is a potent fragrant amino acid and a building block for proteins. Tyrosine is found in many high-protein foods such as cheese, chicken, and eggs. While supplementing, Tyrosine is a precursor to neurotransmitters, and is converted into L-DOPA and then into active catecholamines (adrenaline/epinephrine, noradrenaline/norepinephrine, and dopamine). These catecholamines are used in many different cognitive functions. Being an adaptogen, and having nootropic properties, Tyrosine supplements help with performance during times of stress. Many people also report that it helps significantly with fatigue from stress. Tyrosine can cause an increase in norepinephrine and dopamine in the brain, which can lead to increased energy, memory, attention, alertness, wakefulness, and improved moods, thus relieving depression.[1]

Benefits

Tyrosine is an amino acid which is naturally produced in the body from another amino acid known as phenylalanine. It is most commonly used in protein supplements to relieve of an inherited disorder called phenylketonuria (PKU). People having this disorder can’t process phenylalanine properly, and they fail to make tyrosine. So, supplemental tyrosine can relieve this. Tyrosine is also commonly used to improve learning, memory, and alertness, especially during stressful situations.[2]

  • Improves mental performance in stressful situations [3]
  • Improves cognitive performance and reduces blood pressure [4]
  • Enhances working memory [5]
  • Helps those with phenylketonuria [6]
  • Reduces depression [7]
  • Is a building block of thyroid hormones [8]
  • Helps people who have Parkinson’s disease [9]
  • Improves mood [10]
  • Enhances physical and exercise performance [11][12]
  • Increases dopamine levels in the brain [13]
  • Helps with attention-deficit/hyperactivity disorder (ADHD) [14]
  • Reduces stress levels [15]
  • Improves alertness [16]
  • Improves sleep [17]

The most interesting potential benefits of Tyrosine may be that it is effective at reducing stress levels. And it is believed to be connected with the production of stress hormones Epinephrine and Norepinephrine. The supplement can also benefit those who are sleep deprived. A study shows that Tyrosine can significantly improve working memory in women during a mentally demanding task, compared to a placebo. Working memory is something that plays an important role in concentration and following instructions.[18]

How it works

Tyrosine is used by the body to make chemical messengers that are involved in conditions involving the brain such as mental alertness.
Tyrosine is produced in cells by hydroxylating the essential amino acid phenylalanine. This relationship is much like that between cysteine and methionine. Half of the phenylalanine required goes into the production of tyrosine; if the diet is rich in tyrosine itself, the requirements for phenylalanine are reduced by about 50%. The mechanism of L-tyrosine’s antidepressant activity can be accounted for by the precursor role of L-tyrosine in the synthesis of the neurotransmitters Norepinephrine and Dopamine. Elevated brain Norepinephrine and Dopamine levels are thought to be associated with antidepressant effects.[19]
Moreover, by increasing the levels of the neurotransmitters like Epinephrine, Norepinephrine, and Dopamine, Tyrosine can be able to impact a wide range of processes and functions within your body, especially, the functions that are related to alertness, attention and focus in the brain. Tyrosine helps in the functioning of organs responsible for the making and regulation of hormones all over the body, for example, the adrenal, pituitary, and thyroid glands.

Considerations

Tyrosine supplements are generally considered safe and well-tolerated. It may be safe when taken by the adults for a short time or when applied to the skin. However, some users may experience some adverse effects such as nausea, headache, fatigue, and heartburn. Other side effects may be upset stomach and intestinal discomfort.
Lack of enough information about the safety of Tyrosine, don’t give this supplement to the children and pregnant and breast-feeding. Tyrosine is used by the body to make thyroxine, a thyroid hormone. Since taking extra tyrosine may increase thyroxine levels too much, it may make hyperthyroidism and Graves disease worse. So, if you have one of these conditions, don’t take tyrosine supplements. It is always wise to consult a doctor before starting any supplement.

Recommendations

There is a wide range of doses of Tyrosine used for different purposes. A general dosage range of 500-2000 mg approximately 30-60 minutes before any acute stressor or exercise is taken.
Similarly, for mental performance a single dose of 100-300 mg/kg, for memory 150-300 mg/kg, and for improving alertness following the loss of sleep, 150 mg/kg of Tyrosine in a split dose can be used. For phenylketonuria (PKU), Foods and medical foods providing 4-6 grams of tyrosine daily may be recommended.
You are suggested to consult your physician or healthcare provider to determine an appropriate dose for you.

Sources