Tyrosine Fights Stress

Stress is an unavoidable part of modern life, and an enormous amount of research has been directed at stress and how it affects the human body, especially the mind. Being under stress has major effects on the brain, including deficits in short-term memory.

What goes on in the brain of someone under intense or chronic stress? Earlier research using animals under stress demonstrated a significant drop in brain chemicals called catecholamines. These include two major neurotransmitters: dopamine and norepinephrine.

Norepinephrine makes you more alert, helps focus attention, and plays an important role in memory. We remember things better that excite us. When stress reduces catecholamine levels, it has several effects, including depression, loss of motivation, and increased difficulty focusing attention.

Studies using normal young women found that purposely depleting tyrosine and then exposing them to stress greatly increased their anxiety and irritability, and worsened their mood.

This occurred within five hours of lowering tyrosine blood levels. (For more information on ways to treat stress and anxiety, read my report "Anxiety, Panic Disorder & Migraines: Fight Back Using Nature’s Elixier’s.")

Another study, which looked at how low tyrosine affects memory, found that it impaired spatial memory — that is, remembering the locations of objects on tests. It appeared that the major effect was on frontal lobe function — that is, executive functions such as being able to plan ahead and shifting one’s focus from one thought to another.

Low tyrosine in the diet affects brain levels of dopamine which impairs mood and motivation and puts a person at risk for Parkinson’s disease. Several studies have shown that oral ingestion of tyrosine (100 mg per kilogram of weight per day) could double blood and spinal fluid levels of tyrosine and increase brain levels of norepinephrine and dopamine.

But can tyrosine improve depression, insulate us against stress, and reduce the symptoms of Parkinson’s? In fact, it appears that tyrosine may be able to do all of these things.

One of the most stressful situations a person can experience is military combat. Several studies examined the effect of tyrosine supplementation on combat stress or other forms of intense stress in soldiers. Most of these studies found that tyrosine supplementation significantly improved resistance to stress, including better sleep, mental focus, and memory, along with more energy.

Again, tyrosine improved these behavioral functions only when a person was under stress — it had no effect under non-stressful situations.

More recent evidence suggests that stress — especially the extreme effects of chronic stress (post-traumatic stress syndrome) — is caused by prolonged brain inflammation combined with immunoexcitotoxicity. (For a detailed discussion on inflammation and its role in many diseases, see my newsletter "Inflammation: The Real Cause of Most Diseases.")

How does tyrosine help immunoexcitotoxicity? Recent studies found that when the brain’s norepinephrine levels are low, it becomes more inflamed because one function of norepinephrine is to protect the brain from inflammation. While I would caution against taking high doses of tyrosine, doses in the range of 500 mg to a gram three times a day appear to be safe. Take on an empty stomach, about 45 minutes before a meal.

It is also a good idea to have a urine test for tyrosine to see if you are deficient before starting supplementation. Tyrosine supplements should not be given to infants or children, as it can show some toxicity in rare instances.