Anyone who’s familiar with American Thanksgiving traditions has heard the myth of Tryptophan in turkey. This natural compound presumably is responsible for inducing sleepy feelings following the conventional feast.
In addition to the hypoglycemic load of heavy eating and the stress of long family dinners, the legend of turkey and Tryptophan is true. The presence of Tryptophan in this and many other staple foods may induce feelings of calm and prompt healthy sleep.
Not only that, the body uses L-Tryptophan as an essential building block of several key neurochemicals. Let’s take a look at how this simple compound interacts with our emotional health and physical state. We’ll also explore the value and safety of Tryptophan supplements, including 5-HTP.



- Precursor for serotonin synthesis
- Supports a calm, relaxed mood
- Promotes restful sleep patterns
What Is Tryptophan?
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L-Tryptophan is a naturally occurring amino acid found in food. It is required for basic body and mind function, yet the body cannot produce it on its own. For this reason, we refer to Tryptophan as an essential nutrient.
In addition to Tryptophan in turkey, it can also be obtained from chicken, almonds, sunflower seeds, mushrooms, kale, cheeses, and bananas, among many other common dietary items.
Once consumed, the body metabolizes Tryptophan into an intermediate chemical called 5-HTP (5-Hydroxytryptophan). This substance is the chemical precursor for Serotonin, the chief neurotransmitter related to calm mood. It is from Serotonin that Tryptophan derives most of its famous effects.
Serotonin’s Role in the Brain
Serotonin is responsible for facilitating communication within the brain between nerve cells. It is what is known as an inhibitory neurotransmitter which means it prevents over-stimulation and anxiety within the brain. An ample supply makes thoughts flow easily and naturally, and helps to manage the frenetic signals associated with stress.
When the chemical reaches serotonergic receptor sites on neurons within the brain, it prevents excessive firing of neurons and contributes to feelings of peacefulness, contentedness, and calm.
When the brain experiences a Serotonin deficiency, the symptoms of depression may manifest, while anxious thoughts proliferate unchecked. If food sources of Tryptophan are not enough to correct these imbalances, some form of Serotonin-boosting supplement may be necessary.
Does Tryptophan in Turkey Actually Make Us Drowsy?
It’s true, Tryptophan in turkey can cause some drowsiness. It does this in part because some ingested Tryptophan will convert into Melatonin, the hormone which is released by the body to regulate healthy sleep cycles.
In addition to the general states of calm that Tryptophan’s Serotonin effects will create, the release of Melatonin can have a sedative effect. This is exaggerated when combined with the kind of heavy meal associated with traditional holiday dinners.
However, it is interesting to note that the L-Tryptophan found in turkey is not highly bio-available and can take several hours for effects to manifest. This is because when you eat a large meal like turkey with high quantities of protein, you are consuming a number of different amino acids that are all competing with each other to be transported throughout the body.
This means that the proportional increase in Tryptophan levels in the brain after you eat turkey is much lower than the actual levels of this amino acid that you are consuming.
As such, it is not true that all of those sleepy and satisfied feelings you experience after eating turkey are caused by the presence of Tryptophan. The extra-large fat and carbohydrate laden meal takes a lot of energy for the body to break down, and this adds to sluggish and tired feelings.
Other Tryptophan Benefits
Tryptophan in turkey or as a supplement can both provide improved sleep, however the typical dosage from a serving of turkey – around 500 mg – may not constitute a strong enough dose for severe sleeplessness.
Of course, it would be impractical for most people to eat large turkey dinners nightly. A Tryptophan supplement of some kind may provide relief naturally.
Many people take Tryptophan in some form as a sleep aid. It is also possible to take 5-HTP or Melatonin directly as sleep aids for more powerful effects.
In addition to a good night’s sleep, an L-Tryptophan supplement can deliver a wealth of emotionally balancing benefits. Mood control is an issue for all people living in the modern world, as the amount of stress and information which most people process in a given day can lead to mood swings and energy depletion quite easily.
Tryptophan and 5-HTP can help healthy people maintain a perception of calm and emotional control regardless of stress.
For people suffering form depression, Tryptophan may lift feelings of despair, listlessness, and hopelessness. It can also quell anxious, hyperactive thoughts. For this reason some people also use it for ADHD and anxiety.
Another interesting benefit of Tryptophan supplements is safe weight loss. Like many amino acids, it has an increasing effect upon metabolism while acting as an appetite suppressant. You will sometimes see it or 5-HTP as an ingredient in diet pills.
Is Tryptophan in Food Safer Than Pills?
Some people assume that consuming Tryptophan in turkey is safer than taking it as a supplement. This fear is usually based upon the health scares connected to Tryptophan supplements in 1989 – 1990. At that time, a rare disease called EMS (eosinophilia-myalgia syndrome) affected 1500 people and resulted in 35 deaths.
In time, it was deduced that these incidents were caused by contamination at a single manufacturer’s plant in Japan, and were not connected to Tryptophan itself. Today, the FDA has approved Tryptophan as a safe and effective remedy, with the coveted GRAS (generally regarded as safe) rating.
Most people who take L-Tryptophan supplements at recommended dosages can expect to experience no to mild side effects. Mild side effects that have been reported include nausea, heartburn, stomachache, vomiting, and diarrhea.
More severe side effects can be seen if Tryptophan is taken in very high dosages (over 6 g per day) or if combined with other Serotonin-concentration altering compounds such as antidepressants of the SSRI or MAOI classes. This combination can cause an excess of Serotonin in the brain, which can lead to Serotonin Syndrome.
Symptoms of Serotonin Syndrome include excessive sweating, fever, changes in blood pressure, agitation, and an irregular heartbeat. In extreme cases, if left untreated, Serotonin Syndrome can be fatal.
It is recommended to speak with your doctor before beginning any new supplements. Your doctor will be able to determine the most appropriate dosage for your needs, and determine if the supplement will interact with any existing medications.
Recommendations for Supplementation
Many people choose to forgo pure Tryptophan supplements, opting instead to take 5-HTP as a standalone supplement. This compound, which is the product of Tryptophan and a more direct pre-cursor to Serotonin, produces all of the same effects as Tryptophan, but some users say it works faster and the effects are stronger. Some people find 5-HTP slightly easier to tolerate, as less energy is spent by the body converting it from Tryptophan.
Whether you choose to consume Tryptophan from turkey and other food sources, L-Tryptophan supplements, or in the form of 5 HTP, this natural compound can help enhance the mood and improve sleep.
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Article last updated on: March 13th, 2018 by Nootriment