Tryptophan is a Serotonin-boosting supplement that is used to enhance mood and reduce appetite for weight loss. Derived naturally from food sources, Tryptophan is an amino acid and an essential building block of Serotonin.
But dietary sources of the compound may not be enough to offset more intense emotional imbalances, such as depression or anxiety. In these cases, supplementation is more effective for increasing Serotonergic activity in the brain.
The following is a summary of what we know about the links between Tryptophan and Serotonin. Is Tryptophan supplementation considered safe? Read on to find out if this natural mood lifter belongs in your mental health regimen.



- Precursor for serotonin synthesis
- Supports a calm, relaxed mood
- Promotes restful sleep patterns
Tryptophan and Serotonin
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Amino acids are organic compounds which each play unique and important roles in human biology, including building proteins, hormones, and neurotransmitters. One of these compounds, L-Tryptophan, is widely found in dozens of staple foods in the human diet.
Foods high in Tryptophan include most animal sources, including meats such as beef, buffalo, chicken, and turkey; some fish including tuna and halibut; as well as eggs and dairy products. Vegetables like Brussels sprouts and kale and fruit like banana also contain smaller amounts of Tryptophan.
Once consumed, Tryptophan helps the body form proteins, and is the key ingredient in the neurochemicals Serotonin and Melatonin. Serotonin helps with digestion, improves nerve cell communication, regulates blood pressure, and is directly connected to mood and mental wellness.
This last quality is what makes it important for cognitive and emotional imbalances. A deficiency in L-Tryptophan leading to low levels of Serotonin may result in over-reaction to stress, exaggerated symptoms of depression, and difficulty managing chaotic thoughts. For this reason, many people choose to take some form of Serotonergic supplement in addition to acquiring Tryptophan from food sources.
Benefits of Tryptophan for Serotonin Levels
Tryptophan from either the diet or supplements travels to the liver, where it is broken down into 5-Hydroxytryptophan (5-HTP) and other metabolites like niacin (Vitamin B3). The 5-HTP travels through the bloodstream to the brain, where it crosses the blood brain barrier and enters the brain. Once in the brain, the 5-HTP is converted to Serotonin.
Once the Tryptophan-Serotonin pathway is activated, a host of mind and body benefits begin. The mechanisms of action for this supplement involve inhibitory pathways in the brain that control anxious thoughts, promote relaxation, and enhance feelings of well-being.
Agitated thoughts and emotions may be calmed, making general stress triggers easier to manage. Attention span and mental focus is improved, as distractions are reduced. Increases in Tryptophan intake from food or supplements may help ease social anxiety and panic attacks.
Tryptophan supplements have also been used for depression. User reviews say that L-Tryptophan helps improve energy levels, improve sleeping, and diminish the overall sense of hopelessness.
Melatonin is the main hormone responsible for maintaining proper circadian rhythms (healthy sleep/wake cycles) in the body. During the day, production of Serotonin is high, and production of Melatonin is low. However, when light levels drop in the evening, Serotonin in the brain is converted into Melatonin at higher rates to prepare the body for sleep.
Some people use Tryptophan for sleep disorders, including chronic insomnia, because of the relationship between Melatonin and Tryptophan. Elevated levels of Melatonin can improve the deeper states of sleep that are necessary for the immune system to rejuvenate itself and for maintenance functions to occur in the brain.
Serotonin has also been observed to moderately increase metabolism, making workout and weight loss goals more attainable. The increased Serotonin levels that Tryptophan can cause promote a feeling of fullness which can reduce appetite and unhealthy food cravings.
Using 5-HTP to Boost Serotonin
While there are a number of commercial Tryptophan supplements on the market, many people choose to take the compound in the form of 5-HTP instead. 5 HTP is naturally synthesized directly from Tryptophan by the body. It is an intermediate step which then results in increased amounts of Serotonin.
In almost every way, a 5-HTP supplement produces equivalent effects as a Tryptophan supplement. However, the effects occur in a shorter time-frame and may be slightly more potent.
When you supplement directly with 5-HTP as opposed to taking L-Tryptophan pills, you eliminate the conversion step required to transform L-Tryptophan into 5-HTP. This is believed to reduce the incidence of side effects in some users as it requires less digestive processing.
The use of 5-HTP as a general hangover cure has gained popularity in recent years. While 5 HTP does not have any specific effects which directly target hangover, it is able to correct common Serotonin depletion that accompanies heavy drinking and partying, hence its reputation in this area.
Can Tryptophan Produce Too Much Serotonin?
A safe, effective dosage of Tryptophan for Serotonin production will vary person to person depending on many factors including age, weight, physiology, and personal sensitivities.
The below recommendations are guidelines only; it is recommended to speak with your doctor before beginning any new supplements to determine the best dosage for your needs.
For most people, 500 mg per day is considered a baseline dosage. Dosages up to 6 grams per day have been used safely, but care should be taken with doses this large. Most people who take L-Tryptophan supplements can expect to experience no to mild side effects. Some mild side effects that have been reported include nausea, heartburn, stomachache, lightheadedness, headache, drowsiness, vomiting, and diarrhea.
Tryptophan can be taken safely in combination with 5 HTP capsules, which may increase the amount of Serotonin and the speed at which it is produced. However, this practice can also increase sedation and drowsiness, so individual reactions should be observed with caution when trying it.
In cases of Tryptophan overdose, or if Tryptophan is combined with other Serotonin-concentration altering compounds, than an excess of Serotonin may occur in the brain. This condition is known as Serotonin Syndrome.
Serotonin Syndrome is characterized by symptoms including excessive sweating, irritability, dizziness, fatigue, confusion, changes in blood pressure, agitation, extreme headache, and irregular heartbeat. In severe cases, if it is left untreated, Serotonin Syndrome can be fatal.
To avoid side effects related to excessive Serotonin in the brain, it is advised that you adhere to recommended dosages of between 500 mg to 6 grams of L-Tryptophan powder or capsules per day. You should not combine Tryptophan with certain drugs such as antidepressants (e.g. SSRIs or MAOIs) which influence Serotonin receptors in the brain. Consult with your physician to learn more about the safe usage of this natural supplement.
Is Tryptophan a Safe Serotonin Supplement?
Tryptophan is not water soluble, which means that it can build up to toxic amounts if taken in extreme excess. However, this type of toxicity is rare, and had nothing to do with the health concerns which plagued the supplement a few decades ago.
In 1990, as many as 1500 people contracted a serious illness known as Eosinophilia-Myalgia Syndrome (EMS) when taking Tryptophan supplements. Many people were hospitalized, and there were 35 reported deaths.
The sale of Tryptophan supplements was temporarily banned by the FDA, and investigations were undertaken to determine the cause of the EMS causes. After years of investigation, it was determined that this condition was not the result of Tryptophan’s mechanism of action. All of the cases of EMS were linked to a contaminated batch of Tryptophan from a manufacturer in Japan.
The FDA lifted the ban on Tryptophan supplements, and has since added Tryptophan to its Generally Regarded as Safe (GRAS) list of foods and food supplements.
Other Ways to Stimulate Serotonin
In addition to 5 HTP and Tryptophan Serotonin supplements, there are other natural compounds which can generate similar effects. One of the most common is L-Theanine, a glutamic acid which stimulates both Serotonin and Dopamine production. This supplement is a well-known anxiolytic and stress-buster, and is included in several combination mental health stack products as a result.
Another Serotonin supplement is Griffonia Seed Extract. Griffonia simplicifolia is the African plant that 5-HTP supplements are derived from. Griffonia seeds contain up to 20% 5-HTP by weight.
Any of these methods are viable therapies for increasing Serotonin levels in the body. Used responsibly, supplements such as 5-HTP, L-Theanine, or Tryptophan for Serotonin can lift mood, deliver calm in times of stress, and improve sleep for users.
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Article last updated on: April 28th, 2018 by Nootriment