Tyrosine – an answer for a better mind, memory, mood and sleep

The amino acid supplement tyrosine, sold in health food stores, can help improve mood, sleep and alertness, according to some research. Tyrosine has been called the ‘anti-depressant amino acid’ because of its ability to boost our mood. It is used to make adrenaline, noradrenaline and dopamine – chemicals called neurotransmitters, which all affect our mind. Can taking a tyrosine supplement benefit you?

What is tyrosine and how does it work?
Can we buy tyrosine as a supplement?
Which foods are good sources of tyrosine?
What is tyrosine taken for?
What evidence is there that tyrosine works?
Does tyrosine have any side effects?
What medications can tyrosine interact with?
Who should avoid taking tyrosine?

What is tyrosine and how does it work?

Tyrosine is an amino acid. Amino acids are the building blocks of proteins. Tyrosine is a building block for the body’s two main stress hormones adrenaline and noradrenaline, which are also neurotransmitters. Neurotransmitters are vital chemicals that affect mood and help nerve cells communicate with each other. A neurotransmitter imbalance can cause a range of mental health problems, including depression and anxiety.

Our body makes tyrosine from the amino acid phenylalanine. According to WebMD, tyrosine is used in protein supplements to treat an inherited disorder called phenylketonuria (PKU). People with this problem can’t process phenylalanine properly, so they can’t make tyrosine. They take tyrosine to meet their bodies’ needs.

The University of Maryland Medical Center (UMMC) says tyrosine helps make melanin. This is the pigment that gives skin and hair its color.

Tyrosine helps several organs make and regulate hormones, such as the adrenal, thyroid and pituitary gland.

Can we buy tyrosine as a supplement?

Yes, we can buy tyrosine as a supplement. It is sold in tablet, capsule and powder form. In Australia we can buy it from health food stores.

Which foods are good sources of tyrosine?

Many foods contain tyrosine. Good sources include:

• meat (including poultry)
• fish
• eggs
• beans
• dairy products
• soy products
• nuts
• pumpkin seeds
• sesame seeds

What is tyrosine taken for?

Tyrosine has been taken as a supplement for many things such as:

• helping reduce stress
• depression
• anxiety
• attention deficit hyperactivity disorder (ADHD)
• schizophrenia
• improving memory and mental function
• improving alertness after lack of sleep and those tired with jet lag
• suppressing appetite
• the inability to stay awake (narcolepsy)
• improving sports performance
• premenstrual syndrome (PMS)
• Parkinson’s disease
• Alzheimer’s disease
• chronic fatigue syndrome (CFS)
• alcohol and cocaine withdrawal
• heart disease and stroke
• impotence
• low sex drive
• a sun tanning agent
• applying to the skin to reduce age-related wrinkles

What evidence is there that tyrosine works?

Nutritionist Patrick Holford, in his book Optimum Nutrition for the Mind, says tyrosine works well for dopamine-dependent depression. A pilot study on 12 hospital patients in France found 3,200mg of tyrosine a day significantly improved mood and sleep on the very first day.

Holford also writes that the military knows tyrosine improves mental and physical performance under stress. Twenty-one cadets in the Netherlands went on a demanding one-week military combat training course. Ten cadets were given a drink with 2 grams of tyrosine a day, and the remaining 11 were given an identical drink without tyrosine. Those on tyrosine were better at memorising tasks and tracking the tasks they had done.

There is no scientific proof that tyrosine works for many of the problems it is taken for. This is because no studies have been done on the effect of tyrosine on the problems, or more research is needed to see if tyrosine is helpful as, for example, there is inconclusive or mixed evidence for how well tyrosine works.

Does tyrosine have any side effects?

The Swedish Medical Center in USA says tyrosine is generally safe, but in high doses some people might:

• have nausea
• get diarrhea
• vomit
• feel nervous

WebMD says side effects can include:

• headache
• fatigue
• heartburn
• joint pain

What medications can tyrosine interact with?

The UMMC says if you take any of the following medication, talk to your doctor before taking tyrosine. The amino acid can interact with the following drugs to cause health problems:

• the antidepressants Monoamine Oxidase Inhibitors (MAOIs), including Isocarboxazid (Marplan), Phenelzine (Nardil), Tranylcypromine (Parnate) and Selegiline
• thyroid hormone
• Levodopa (L-dopa) for Parkinson’s disease

Who should avoid taking tyrosine?

Not enough is known about how safe taking tyrosine is during pregnancy and breast feeding, so do not take tyrosine if this applies to you.

People with an overactive thyroid (hyperthyroidism) or Graves disease should not take tyrosine. The body uses tyrosine to make the thyroid hormone thyroxine. Taking extra tyrosine might increase thyroxine levels too much, making these health problems worse.

The UMMC says there is no dietary recommendation for tyrosine for children. Talk to your doctor before giving a child a tyrosine supplement.

People who have migraine headaches should avoid tyrosine, as it can trigger migraines and upset the stomach.

People with PKU should talk to their doctor before taking tyrosine. This is because taking tyrosine greatly increases the risk of bad side effects in people with this health problem.

written by Nyomi Graef

References:
Holford, P, 2003, Optimum Nutrition for the Mind, London, UK: Piatkus

Monson, K et al., 2008, L-Tyrosine Safety, eMedTV,
http://depression.emedtv.com/l-tyrosine/l-tyrosine-safety.html

Monson, K et al., 2008, Tyrosine and Pregnancy, eMedTV,
http://mental-health.emedtv.com/tyrosine/tyrosine-and-pregnancy.html

Tyrosine, 2009, WebMD,
http://www.webmd.com/vitamins-supplements/ingredientmono-1037-TYROSINE.aspx?activeIngredientId=1037&activeIngredientName=TYROSINE&source=3

Tyrosine, 2010, Natural Medicines Comprehensive Database,
http://naturaldatabase.therapeuticresearch.com/nd/Search.aspx?cs=&pt=100&id=1037&&AspxAutoDetectCookieSupport=1

Tyrosine, 2010, Swedish Medical Center,
http://healthlibrary.epnet.com/GetContent.aspx?token=af362d97-4f80-4453-a175-02cc6220a387&chunkiid=21794

Tyrosine, 2010, University of Maryland Medical Center,
http://www.umm.edu/altmed/articles/tyrosine-000329.htm

Tyrosine, 2010, Wikipedia,
http://en.wikipedia.org/wiki/Tyrosine

Winter Griffith, H, 1995, The Vitamin Fact File, London, UK: Diamond Books