What Is 5-HTP? Benefits, Uses, and Safety of This Serotonin-Boosting Supplement

Understanding 5-HTP: The Building Block of Serotonin

5-HTP is a popular dietary supplement consumed for several reasons. The name is kind of wonky, but it is short for 5-hydroxytryptophan. The key word being tryptophan, which is an essential amino acid that we naturally obtain from protein sources in our diet. Consumed tryptophan can be converted into the 5-HTP form, which can then further be transformed into the neurotransmitter serotonin. Serotonin plays many vital roles in metabolism and supplementing 5-HTP is typically done towards an aim of enhancing at least one of these functions.

The Role of Serotonin: Mood, Sleep, and Digestion

So, what does serotonin do? Serotonin is a neurotransmitter that plays several key roles, among them:

Mood stabilization: Low levels of serotonin are linked to symptoms of depression and anxiety, such that first-line treatments for depression and anxiety disorders are typically a class of drugs known as SSRIs, or selective serotonin reuptake inhibitors. These drugs elevate levels of serotonin in the brain, which is associated with a reduced severity of anxiety and depression.

Sleep: Serotonin can be converted into melatonin, which is a hormone that is vital to inducing sleep and maintaining sleep quality.

Digestion: Everything is connected! Poor sleep quality is related to a less-diverse, gut microbiome and a greater incidence of gastrointestinal problems. Adequate serotonin levels are vital to both sleep and digestion.

5-HTP Supplementation: The Evidence so far…

In theory, ingesting 5-HTP could increase serotonin production, enhancing its many functions.  Does it work? The research so far is mixed, with some published clinical trials showing promising results, while others show little effect. In terms of mood enhancements, several studies linking 5-HTP supplementation with improved outcomes in patients with depression.  

Supplementing 5-HTP for 12 wks has also been found to improve sleep quality and increase gut microbiome diversity. However, another study found 15 weeks of 5-HTP supplementation did not alleviate fatigue in patients with irritable bowel disease.

There is even some evidence that 5-HTP supplementation (100mg/day for 8 wks) can help reduce body fat. This is possibly due to greater feelings of satiety following 5-HTP supplementation.

5-HTP Dosage and Safety: What You Need to Know

Recommended Dosage

Most studies found efficacy from a 5-HTP dose of 100mg/day, which appears to be adequate to induce beneficial changes. Higher doses can increase the odds of gastrointestinal side effects, including nausea, diarrhea, and vomiting, thus are not recommended.

Potential Side Effects: Interactions and Precautions

5-HTP supplementation has generally been found to be safe. It is theoretically possible to increase serotonin levels to the extent of developing a condition called serotonin syndrome, which is characterized by high blood pressure, dizziness, disorientation, hyperthermia. Serotonin syndrome is potentially fatal if untreated. Happily, there are no known cases of serotonin syndrome documented after consuming 5-HTP supplementation alone in humans, lab rats have had some issues. The fear is that combining 5-HTP supplements with other treatments that increase serotonin (i.e. SSRI drugs such as Zoloft or Prozac) could make this possible.   

Consulting a Healthcare Professional: Essential Advice

Which leads us to this: 5-HTP supplements might have a positive impact on your health. As with all supplements, I recommend considering the supplement as one potential piece to add to a regimen that includes a balanced diet, regular exercise, and good sleep hygiene. In addition, I would only consider supplementing 5-HTP after a discussion with your medical provider.

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