Within our central nervous system Serotonin plays a critical part in in the regulation of Depression, Anxiety, Sleep, Aggression, Temperature, Appetite, Sexual Behaviour and the Sensation of Pain. Cells in other parts of the body also use and make Serotonin, but all Serotonin used by our Brain Cells has to be made within the Neurons, as Serotonin cannot cross the blood-brain barrier. Serotonin is produced by an Amino Acid called Tryptohan.
5-Hydroxytryptophan, (5-HTP), is also an Amino Acid naturally produced by the body from the essential Amino Acid Tryptohan through a process called Enzyme Tryptophan Hydroxylase.  The action of Tryptophan Hydroylase can be inhibited by many different influences, some of these include, Stress, Vitamin B6 deficiency, and Insulin Resistance, thus making the Tryptophan unavailable for Serotonin production.  As mentioned earlier, if not enough Serotonin is produced then the regualtion of  Depression, Anxiety, Sleep, Aggression, Temperature, Appetite, Sexual Behaviour and the Sensation of Pain, may be effected.
When 5-HTP is taken as a dietary supplement by an oral dose, the natural conversion from Tryptohan to   5-HTP via Enzyme Tryptophan is bypassed, and around 70% of the supplement will end up in the bloodstream 1+2 Unlike Tryptohan; which can be affected by the prescence of other Amino Acids and shunted into niacin or protein production, 5-HTP is not affected by other Amino Acids, and can therefore be taken with meals without it reducing it’s effectiveness.
Where as Tryptophan requires the use of a transport molecule to enter the Central Nervous System, and has to share the transport molecule with other Amino Acids; which may inhibit the Tryptophan transport into the brain; 5-HTP does not require a transport molecule, and can easily cross the blood – brain barrier³.
Benefits of Taking 5-HTP
Mood Disorders
5-HTP helps to promote a healthy mood balance4 and for this reason many people take 5-HTP to help combat bouts of depression.
In a review of seven double blind controlled trials of 5-HTP for depression5it was found that there was an improvement in mood whilst taking 5-HTP. In another controlled trial 45 patients suffering with depression were given either 5-HTP or a placebo for 20 days. The results found that 5-HTP was statistically superior to the placebo. Studies have also shown that people taking 5-HTP showed a reduction in depressive episodes, and suffered fewer side effects than when taking pharmaceutical antidepressants6.
Headaches / Migraines
Some studies have successfully proven that taking a supplement of 5-HTP to prevent migraines, tension headaches and juvenile headaches is beneficial 7-13as low seretonin levels play a key role in the onset of headaches.
Weight Management
When we diet our seretonin levels drop dramatically14-16, which can cause us to have carbohydrate cravings. Because of these carbohydrate cravings we eat, and therefore do not loose the desired weight. There have been three major trials in obese patients and they have all proven that a supplementation of 5-HTP can help decrease the amount of food that you eat.17-19
Fatigue
In a cross over trial of 6 patients it was found that 5-HTP significantly subjective and objective measures of central fatigue.
Things to consider before taking 5-HTP
Because of Serotonin Syndrome, 5-HTP should not be taken in conjunction with any other Anti-Depressant Medication, including, but not limited to:
- SSRI’s (Selective Serotonin Reuptake Inhibitor) – Prozac (Fluoxetine), Paxil (Paroxetine), Zoloft (Sertraline), Luvox (Fluvoxamine).
- MAOI’s (Monoamine Oxidase Inhibitors) – Nardil (Phenelzine), Parnate (Tranylcypromine).
Serotonin Syndrome can occur following inadvertent interactions between drugs, an adverse reaction to a drug, or the recreational use of certain drugs. It is actually a form of poisoning, and occurs when there is excess serotonergic activity at the Central Nervous System. This excess in Serotonin can cause mortality. The signs of Seretonin Syndrome are, (but not limited to); agitation, confusion, delirium, tachycardia, diaphoresis, and blood pressure fluctuations.
5-HTP and Tryptophan
Tryptophan is a susbstance that has been banned due to it’s link with Eosinophilia-Myalgia Syndrome (EMS). In 1989 an epidemic of EMS was at it’s peak due to a contaminated batch of Tryptophan. The contaminated batch was related to one specific company’s production methods, where they used bacterial fermentation and subsequent inadequate filtration. Unfortunately, due to this contaminated batch of Tryptophan more than twenty-seven deaths occured. Please note; at this present time 5-HTP has not been asociated with any of the problems that Tryptophan encountered.
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