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  Tryptophan / 5 HTP  
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An essential amino acid, tryptophan is the least abundant amino acid found in foods. It is used by the brain to produce serotonin; it is a natural relaxer, helps alleviate insomnia, reduces anxiety and depression and helps treat migraine headaches. The richest dietary sources include fish, meat, dairy, eggs, nuts and wheat germ, but tryptophan tends to be deficient in most dietary proteins. High corn diets have been associated with outright deficiency symptoms. The RDA for tryptophan is 0.2gm per day, while the average daily intake is 1-1.5gm per day. The therapeutic range is up to 4gm per day, and medical supervision of treatment can be helpful.

Tryptophan is often given with vitamin B6 and magnesium away from meals with a small amount of carbohydrate to facilitate uptake by the brain. To aid in sleep, much of the dose is given before going to bed. If more of a daytime action is being sought, the bulk can be given in the morning. Tryptophan is metabolized into niacin, melatonin and serotonin and has relaxing and calming effects.

5HTP (5-hydroxy tryptophan) is considered by many to be more effective than tryptophan for depression. L-Tryptophan (which is the desired form) is converted to 5HTP before becoming serotonin; taking 5HTP bypasses this first step of the process. The effectiveness of 5HTP may be increased with gingko biloba, St. John's Wort, B-complex vitamins with magnesium, tyrosine, flax seed oil, and ginger. Vitamin B6 and folic acid may assist in the conversion to serotonin. An equivalent dose of 5HTP (compared to 1gm of tryptophan) is about 100mg. Doses of 100mg tid have been used, but it may be best to start at a lower dose and slowly increase as the side-effect of nausea can occur at higher doses. Starting at a lower dose reduces the likelihood of nausea, which usually disappears in less than 2 weeks.

Chromium picolinate helps to promote conversion of tryptophan to serotonin. It accomplishes this by facilitating absorption into muscle tissue of the amino acids that compete with tryptophan for access to the brain.

For depression, 1000-1500mg bid raises serotonin levels but it may take 2 weeks to produce results. If a patient has insomnia along with depression then tryptophan would appear to be even more effective, possibly because both conditions may be due to this deficiency. Care must be taken when using more that one anti-depressant at the same time; a doctor's supervision should be sought when considering switching or combining depression medications.


Tryptophan / 5 HTP can help with the following:
AutoimmuneNot recommended for:
  Lupus, SLE (Systemic Lupus Erythromatosis) / Risk
 Some doctors caution against the use of tryptophan in patients with SLE. Because of abnormal tryptophan metabolism and the possibility of promoting auto-antibody production SLE patients should avoid supplementation with tryptophan or 5HTP unless determined to be tolerated by any particular patient.

Environment / Toxicity

  Seasonal Affective Disorder (SAD)
 Research has shown tryptophan to be as equally effective as light therapy in treating SAD (Lam et al. 1997). The clinical use of L-tryptophan has also specifically been shown to improve response to light therapy (Ghadirian et al. 1998). In clinical studies, SAD patients who were deprived of tryptophan were vulnerable to a relapse of SAD even in summer months (Neumeister 1997, 1998; Kasper 1998).

One study that attempted to separate the effectiveness of light therapy vs. tryptophan found that without adequate levels of tryptophan in the system, the light therapy alone did not provide relief.


  Low Serotonin Level
 Tryptophan is the dietary amino acid precursor for production of serotonin in the body. First it is converted into 5HTP, and then into serotonin. Both supplements are available, but tryptophan may require a doctor's prescription. It is recommended that these be taken under a doctor's supervision.

  Night Eating Syndrome
 Taking Tryptophan or 5-HTP orally causes an increase of serotonin in the brain. It is proven that more than 70% of the nighttime eating is about carbohydrates - foods which are believed to increase the amount of tryptophan available for conversion to serotonin, the calming neurotransmitter in the brain.

Not recommended for:
  Histapenia (Histamine Low)


  Obsessive-Compulsive Disorder (OCD)
 OCD may be related to a central disturbance in serotonin metabolism, a hypothesis which appears to explain the efficacy of serotonin reuptake-blocking drugs. L- tryptophan and 5-HTP are serotonin precursors.

Side effects were mainly drowsiness and headaches in those whose daily doses of L- tryptophan exceeded 6,000mg. [Clinical Psychiatry News, September, 1981] Supplementation may be contraindicated in OCD patients with a history of aggressive behavior since it may increase

 Tryptophan (or 5-HTP), the precursor of the sleep-inducing neurotransmitter serotonin, also has relaxing and calming effects. Serotonin levels are often low among people with anxiety disorders. A recent study found that 44% of alcoholics suffer from anxiety. You can be pretty sure that you are low on tryptophan if you have ever blacked out from drinking. It has been established that low tryptophan stores trigger blackouts.

A combination product called Amoryn contains St. John's Wort, 5HTP, and small amounts of B6, B12 and folic acid. This product may help with anxiety.

 Tryptophan is a precursor to serotonin, a neurotransmitter that is frequently imbalanced in cases of depression. Conventional antidepressants work to increase neurotransmitter levels by blocking their breakdown. Depression associated with menstrual cycles and postpartum depression sometimes respond very well to tryptophan supplementation. Postpartum women usually have high estrogen levels and it has been found that high estrogen levels increase the conversion of tryptophan to niacin. Progesterone and hydrocortisone decrease its conversion. Women on birth control pills, when given vitamin B6 and tryptophan, generally tend to metabolize tryptophan more normally.

The therapeutic efficacy of tryptophan and tyrosine in the treatment of depression has been inconsistent. According to this review article, studies have shown that two subgroups of depressed patients can be delineated. The first subgroup (Group A) has low urinary levels of the norepinephrine metabolite MHPG (3-methoxy-4-hydroxyphenethylene glycol). This group fails to respond to amitriptyline, but shows a favorable response to desipramine or imipramine (which tend to raise norepinephrine levels rather than serotonin). They also exhibit mood elevation after receiving dextroamphetamine. The second group (Group B) has normal or high urinary MHPG levels, fails to respond to imipramine, but responds to amitriptyline (which tends to raise brain levels of serotonin, rather than dopamine or norepinephrine). These patients experience no mood elevation after dextroamphetamine. Group A would be expected to respond to L-tyrosine (a norepinephrine precursor) and group B should respond to L-tryptophan (a serotonin precursor). The biochemical separation of these subgroups may increase the therapeutic predictability of both L-tryptophan and L-tyrosine.

Comment: In my experience, L-tryptophan is effective against depression more often than is L-tyrosine. A careful history, however, may help to identify those cases in which L-tyrosine would be the appropriate amino acid to prescribe. I typically ask depressed patients what medications they have received and which ones have been helpful; I also ask whether they have taken amphetamines and how they have responded to them. It appears, as Buist has suggested, that the information obtained from those questions can help predict who will respond to which amino acid.

Buist RA. The therapeutic predictability of tryptophan and tyrosine in the treatment of depression. Int Clin Nutr Rev 1983;3(2):1-3.

  Tendency Toward Postpartum Depression
 Tryptophan at 1 to 3gm per day can be used to treat a variety of depression syndromes. It is especially effective when treating depression which is accompanied by insomnia. Depression associated with menstrual cycles and postpartum depression sometimes respond very well to tryptophan supplementation. Postpartum women usually have high estrogen levels and it has been found that high estrogens increase the conversion of tryptophan to niacin. Progesterone and hydrocortisone decrease its conversion. Women on birth control pills, when given vitamin B6 and tryptophan, generally tend to metabolize tryptophan more normally.


  Anorexia / Starvation Tendency
 Post-meal plasma amino acids in 13 female patients with anorexia nervosa (mean age 24 yrs.) who were 72% of ideal body weight were compared to those of healthy controls. The data suggest that post-meal brain tyrosine availability was probably improved, while post-meal brain tryptophan was reduced, especially following a protein-rich diet. This may explain the low serotonin metabolism noted in anorectic patients. Since serotonin has been implicated in the control of appetite and macronutrient selection, this may be a self-perpetuating mechanism. [Metabolism 35( 10): pp.938-43, 1986]

Brain tryptophan levels may be reduced in patients who are markedly underweight, which normalizes after weight is gained. [Biol Psychiatry 23: pp.102- 5, 1988]

Evaluation of serotonin and tryptophan metabolism suggest that biological differences may contribute to the higher prevalence of eating disorders among women. [Psychol Med 17( 4): pp.839-42, 1987]

  Problem Caused By Being Overweight
 Although used chiefly as an antidepressant, preliminary evidence from three small double-blind placebo-controlled clinical trials suggests that 5-HTP may also help people lose weight. It is thought to work by raising levels of serotonin, which in turn may influence eating behavior. A typical therapeutic dosage of 5-HTP is 100 to 300mg 3 times daily.

  Bulimic Tendency
 Due to the fact that the synthesis of serotonin and melatonin within the brain is dependent on the availability of the amino acid tryptophan, supplementing the diet with tryptophan before going to bed may produce good results in relieving insomnia. Tryptophan tends to work better for acute insomnia (sleep-onset insomnia) than for chronic sleep problems since its greatest effect is to shorten the time it takes to fall asleep after going to bed.

Some 1000 to 2000mg of L-tryptophan are needed in order to increase blood levels sufficiently to induce sleep. However, the lowest dose (often as little as 500mg) that works as a sleep aid should be maintained to continue benefits. The dose may be repeated if one wakes during the night. Doctors often recommend starting with 1gm of L-tryptophan 30-45 minutes before bed, which will reduce the time it takes to fall asleep. If 1000mg is insufficient, the dose may be increased by 500mg each night until either the desired effects are achieved or a total of 3000mg is reached.

Results treating insomnia with tryptophan have been mixed. A 1986 study suggested that L-tryptophan is an effective hypnotic agent only for people with a sleep maintenance problem that is characterized by 3-6 discrete awakenings during the night. [Sleep 1983;6: pp.247-256]


  Restless Leg Syndrome (RLS) / Periodic Limb Moveme
 Tryptophan, a serotonin precursor, has been shown to help a small percentage of RLS sufferers. [Am J Psychiatry 143(4): pp.554-5, 1986]

Nervous System

  Tourette's Syndrome
 The low blood serotonin and tryptophan levels seen in Tourette's syndrome (TS) are consistent with the wide range of behavioral disorders expected in such cases [ Am J Med Genet, Aug 1990;36(4): pp.418-30]. As far as we know, tryptophan therapy for Tourette’s syndrome has not yet been explored. However, TS is quite similar in many respects to obsessive/compulsive disorders which do respond to tryptophan supplementation. This observation provides a ray of hope for individuals trying to cope with the symptoms of TS.


  Tryptophan Need


Not recommended for:
 Foods high in tryptophan and supplemental tryptophan should be removed from the diet as some children with asthma have a defect in tryptophan metabolism and reduced platelet transport of serotonin - a known broncho-constricting agent in asthmatics. Alternatively vitamin B6 could be used to supplement the diet as this aids in the metabolism of tryptophan.

May do some good
Likely to help
Highly recommended
May have adverse consequences


Amino Acid:  An organic acid containing nitrogen chemical building blocks that aid in the production of protein in the body. Eight of the twenty-two known amino acids are considered "essential," and must be obtained from dietary sources because the body can not synthesize them.

Anxiety:  Apprehension of danger, or dread, accompanied by nervous restlessness, tension, increased heart rate, and shortness of breath unrelated to a clearly identifiable stimulus.

BID:  Twice per day.

Carbohydrates:  The sugars and starches in food. Sugars are called simple carbohydrates and found in such foods as fruit and table sugar. Complex carbohydrates are composed of large numbers of sugar molecules joined together, and are found in grains, legumes, and vegetables like potatoes, squash, and corn.

Chromium:  Chromium is a mineral that becomes a part of the glucose tolerance factor (GTF). Chromium aids in insulin utilization and blood sugar control. By controlling blood sugar, chromium helps prevent the damage caused by glucose, which is called glycation. Chromium helps maintain normal cholesterol levels and improves high-density lipoprotein levels. Chromium is also important in building muscle and reducing obesity.

Flax:  Flax Seed or Flax Oil. Flax oil is nutty-flavored oil that is pressed out of flax seeds and is one of the richest sources of Essential Fatty Acids (especially Omega-3 oil), a vital element for good health. The oil making process removes many of the seed's phytoestrogens which offer several health-related benefits including reducing the risk of cancer and alleviating menopausal symptoms. Many choose to use the whole seed because of its fiber and lignan content. Flaxseed oil is light- and temperature-sensitive and must be stored in the refrigerator.

Folic Acid:  A B-complex vitamin that functions along with vitamin B-12 and vitamin C in the utilization of proteins. It has an essential role in the formation of heme (the iron containing protein in hemoglobin necessary for the formation of red blood cells) and DNA. Folic acid is essential during pregnancy to prevent neural tubular defects in the developing fetus.

Gram:  (gm): A metric unit of weight, there being approximately 28 grams in one ounce.

Magnesium:  An essential mineral. The chief function of magnesium is to activate certain enzymes, especially those related to carbohydrate metabolism. Another role is to maintain the electrical potential across nerve and muscle membranes. It is essential for proper heartbeat and nerve transmission. Magnesium controls many cellular functions. It is involved in protein formation, DNA production and function and in the storage and release of energy in ATP. Magnesium is closely related to calcium and phosphorus in body function. The average adult body contains approximately one ounce of magnesium. It is the fifth mineral in abundance within the body--behind calcium, phosphorus, potassium and sodium. Although about 70 percent of the body's magnesium is contained in the teeth and bones, its most important functions are carried out by the remainder which is present in the cells of the soft tissues and in the fluid surrounding those cells.

Melatonin:  The only hormone secreted into the bloodstream by the pineal gland. The hormone appears to inhibit numerous endocrine functions, including the gonadotropic hormones. Research exists on the efficacy of melatonin in treating jet lag and certain sleep disorders. Dosages greater than l milligram have been associated with drowsiness, headaches, disturbances in sleep/wake cycles and is contraindicated in those who are on antidepressive medication. It also negatively influences insulin utilization.

Migraine:  Not just a headache, but a disorder affecting the whole body, characterized by clearly defined attacks lasting from about 4 to 72 hours, separated by headache-free periods; progresses through five distinct phases. Prodrome: experienced by about 50% of migraineurs and starting up to 24 hours before the headache - changes in mood, sensory perception, food craving, excessive yawning, or speech or memory problems. Aura: experienced by about 15% and starting within an hour before the headache - disruption of vision (flashing lights, shimmering zigzag lines, blind spot) or sensation (numbness or 'pins and needles' around the lips or hand), or difficulty speaking. Headache: usually pulsating and occurring on one side of the head, it may occur on both sides of the head and alternate from side to side. Muscles in the neck and scalp may be tender; there may be nausea and the desire not to eat, move, see or hear. Resolution: the headache disappears and the body returns to normal. Resolution may occur over several hours during sleep or rest; an intense emotional experience or vomiting may also end the headache. Postdrome: After the headache stops, the sufferer feels drained, fatigued and tired. Muscles ache, emotions are volatile and thinking is slow.

Milligram:  (mg): 1/1,000 of a gram by weight.

Nausea:  Symptoms resulting from an inclination to vomit.

Niacin:  (Vitamin B-3): A coenzyme B-complex vitamin that assists in the breakdown of carbohydrates, fats and proteins. Essential for the health of the skin, nerves, tongue and digestive system. It is found in every cell of the body and is necessary for energy production. Niacin is also needed for DNA formation.

Protein:  Compounds composed of hydrogen, oxygen, and nitrogen present in the body and in foods that form complex combinations of amino acids. Protein is essential for life and is used for growth and repair. Foods that supply the body with protein include animal products, grains, legumes, and vegetables. Proteins from animal sources contain the essential amino acids. Proteins are changed to amino acids in the body.

RDA:  Recommended Daily Allowance of vitamins or other nutrients as determined by the FDA. U.S. RDAs are more widely used than RDAs, and focus on 3 age groups: Infants of 0-12 months; Children of 1-4 years; Adults and children of more than 4 years.

Serotonin:  A phenolic amine neurotransmitter (C10H12N2O) that is a powerful vasoconstrictor and is found especially in the brain, blood serum and gastric membranes of mammals. Considered essential for relaxation, sleep, and concentration.

TID:  Three times a day.

Tryptophan:  Essential amino acid. Natural relaxant and sleep aid due to its precursor role in serotonin (a neurotransmitter) synthesis. Along with tyrosine, it is used in the treatment of addictions.

Tyrosine:  A nonessential amino acid but may be essential for individuals with certain diseases or nutritional concerns. May be important for neurotransmitter synthesis and mood regulation. May be useful for depression, allergies and addictive states.

Vitamin B6:  Influences many body functions including regulating blood glucose levels, manufacturing hemoglobin and aiding the utilization of protein, carbohydrates and fats. It also aids in the function of the nervous system.