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Better Brain Chemistry with Tryptophan

May 2013

By Travis Harding

Tryptophan Relieves Premenstrual Symptoms

Tryptophan Relieves Premenstrual Symptoms  

No discussion of irritability and “grumpiness” would be complete without mention of premenstrual syndrome and its more disruptive cousin, premenstrual dysphoric disorder. In both syndromes, a reduction in brain serotonin levels is to blame for the dysphoria (state of unease, the opposite of euphoria), mood swings, tension, and irritability that define them.51 Standard drug treatment consists of selective serotonin reuptake inhibitors, with their attendant side effects.52,53

Studies of tryptophan depletion reveal a worsening of premenstrual symptoms, especially aggression, while a small number of studies have now appeared suggesting that tryptophan supplementation is effective at reducing symptoms.54-56 In one study of premenstrual dysphoria, a dose of 6 grams/day produced a significant reduction in dysphoria, mood swings, tension, and irritability, when started on the day of ovulation and continued until the third day of menstruation.55

Consequences of Abnormal Serotonin Function

Abnormalities of Serotonin Function Are Related To:1,2,6

  • Behavioral disorders in geriatric patients
  • Aggressive and self-injurious behavior
  • Sleep disorders
  • Depression and seasonal affective disorder (SAD)
  • Mania
  • Anxiety
  • Obsessive compulsive disorder
  • Eating disorders
  • Schizophrenia
  • Movement disturbances (tardive dyskinesia, akathesia, dystonia)
  • Familial tremor
  • Restless legs syndrome
  • Gilles de la Tourette’s syndrome
  • Multiple sclerosis
  • Parkinson’s disease
  • Huntington’s disease
  • Dementia
  • Substance abuse
  • Hypersexuality


One of the greatest heartbreaks of aging is its association with short tempers, easy frustration, and irritability, resulting in the sometimes accurate stereotype of the “grumpy old man” (or woman).

Today, we recognize that the chronic inflammation that’s part of the aging process eats away at our bodies’ supply of tryptophan, the amino acid needed to produce the “happiness neurotransmitter,” serotonin.

Loss of adequate serotonin in the brain is associated with more than just grumpiness, however. Age-related changes in serotonin levels are responsible for troubling sleep disturbances and for the manifestations of many mental health problems such as depression, anxiety, and post-traumatic stress disorder. Even premenstrual syndrome is now recognized as a consequence of transiently low serotonin levels.

Studies reveal the intimate relationships between tryptophan levels in the blood and serotonin levels in the brain. Tryptophan depletion can replicate symptoms of irritability, mood disorders, anxiety, and stress, while tryptophan supplementation is proving capable of reversing many of these symptoms.

Instead of taking an expensive pharmaceutical drug to boost your synaptic serotonin levels, consider daily tryptophan supplementation to achieve similar results at less cost and greater safety.

If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.

Tryptophan: A Word of Caution

Low to moderate doses of tryptophan (less than about 30 milligrams per pound of body weight, or about 4.5 grams in an average 165-pound adult) are safe and generally free of side effects. However, at higher doses tremor, nausea, and dizziness may occur.

Special caution is called for in those taking anti-depressant drugs called selective serotonin reuptake inhibitors (SSRIs), because these drugs delay normal degradation of serotonin within nerve synapses. Excessive tryptophan in combination with such drugs can produce the “serotonin syndrome,” consisting of delirium, involuntary muscle contractions, high fever, and coma.8

In 1989, a dangerous new syndrome, eosinophilia myalgia syndrome, was traced to contaminated tryptophan supplements, leading the US government to ban tryptophan imports.8 Since that time, tryptophan supplies in the US have been carefully monitored and are safe. Eosinophila myalgia syndrome is entirely unrelated to tryptophan itself, and should not be considered a side effect of supplement use.


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