L-5 hydroxytryptophan is a natural chemical in the body that people can also take as a nutritional supplement. Some people believe that taking the supplement can improve certain aspects of health, including mental health and sleep quality.
The compound is a natural precursor to a neurotransmitter called serotonin, which helps produce "feel-good" chemicals in the brain and body.
However, there is little significant research to prove that L-5 hydroxytryptophan (5-HTP) can offer such benefits.
In this article, learn about the possible benefits of 5-HTP, as well as its possible side effects.
The body produces serotonin through a series of chemical steps, starting with the amino acid L-tryptophan. One of the chemicals on the way from transforming L-tryptophan to serotonin is 5-HTP.
The chemical was only available via prescription until 1995, when the United States Food and Drug Administration (FDA) approved it as an over-the-counter (OTC) supplement.
Manufacturers derive the supplement from the seeds of Griffonia simplicifolia, which is an African plant. The supplement does not naturally occur in foods.
Some people believe that taking 5-HTP can increase the amount of serotonin in the body. Doctors have previously linked a lack of serotonin with a number of medical conditions, including depression.
As a result, some doctors recommend taking 5-HTP along with regular medications for certain conditions.
Many studies into the health benefits of 5-HTP and sleep are based on animal models.
For example, a 2018 study looked the effects of 5-HTP and gamma-Aminobutyric acid (GABA) on fruit flies, mice, and rats. The scientists used caffeine to induce sleeplessness, then they administered the GABA/5-HTP combination.
They found that the combination could induce sleep and seemed to enhance sleep quality and length of sleeping time.
Another review of treatments available for sleep problems found that 5-HTP may be beneficial in treating disorders of arousal, such as sleep terrors and sleepwalking.
Taking 5-HTP may support behaviors that help a person lose weight or maintain a healthy weight.
They then performed an MRI scan while showing participants real food and images of food to see how their brains responded.
A brain response for protein-rich foods was more likely to occur in those who took the 5-HTP supplement than in people who did not.
Protein can help a person maintain a healthy body weight, so the researchers concluded that 5-HTP may help a person lose weight by reducing cravings for unhealthful foods.
It is vital to note that this study was very small, so larger-scale research is necessary to validate these results.
At the end of the study, the women who took 5-HTP reported greater feelings of satiety, or fullness, when eating, which led to a decreased food intake. The women who took 5-HTP also had reduced body mass index (BMI).
While these studies were very small, they showed some promise that 5-HTP could help weight loss efforts.
Selective serotonin reuptake inhibitors are a common treatment for depression. These medications work by preventing the body from breaking down serotonin, thereby increasing the amount that is available in the body.
Some researchers believe that 5-HTP could act in a similar way by increasing the amount of 5-HTP in the body. Unfortunately, there is not a lot of research to support this.
An older meta-analysis examined the results of studies on 5-HTP and tryptophan in relieving depression symptoms. While the authors reviewed more than 100 studies related to the topic, they found that few studies used high-quality methods.
The researchers concluded that there was not enough evidence to say that 5-HTP had a greater effect than a placebo on depression.
However, they did note that some of the studies found that 5-HTP could be better than placebo in some people. These studies were too old, however, to represent the latest clinical research methods.
Another challenge in using 5-HTP to treat depression is that the supplement does not usually last long in the body, which rapidly absorbs and eliminates it.
These characteristics can keep it from being an effective method to treat depression.
If researchers could find a way to make 5-HTP last longer in the body, it may show more promise as a depression treatment, according to one study.
Some natural medicine proponents believe that taking 5-HTP supplements can help reduce anxiety and panic. However, most of the research about 5-HTP and anxiety is 15–20 years old.
One research study from 2002 found that taking 5-HTP reduced anxiety and panic in people with panic disorder. However, the researchers did not find any difference in anxiety in other participants who did not have a panic disorder.
Doctors know that a lack of serotonin is likely to play a role in anxiety and panic. However, studies have not yet proven that using 5-HTP to increase serotonin is an effective strategy for reducing anxiety.
Much of the focus on using 5-HTP for pain relief surrounds the treatment of fibromyalgia, a condition that causes chronic nerve pain. Chronic pain from fibromyalgia can affect a person's sleep and mood.
Studies on 5-HTP and fibromyalgia are limited and too old to provide significant results. A study from 1990, for example, found that taking the supplement may help reduce symptoms in participants with primary fibromyalgia syndrome, but larger and newer studies are necessary to confirm these results.
However, a small study in an animal model found that 5-HTP might reduce the perception of pain.
Supplement manufacturers sell 5-HTP in a variety of dosages. These include 25-, 50-, and 100-milligram (mg) capsules.
Some supplement manufacturers may also add 5-HTP to multivitamins. There is no specific recommended daily allowance for 5-HTP.
Most people will take 50–100 mg per day after starting at a lower dose of 25 mg and increasing the dose weekly.
A person should read their supplement label and talk to a doctor before taking any supplement.
It is vital to remember the FDA do not regulate supplements. A person should purchase supplements from a reputable manufacturer and store them as the label advises.
According to some research, taking 5-HTP may increase serotonin but deplete or reduce the amounts of other neurotransmitters. These include dopamine and norepinephrine.
This side effect could actually make some medical conditions worse. Examples of such conditions include:
- attention deficit hyperactivity disorder
- generalized anxiety disorder
- Parkinson's disease
- seasonal affective disorder
This is more likely to occur when a person has taken 5-HTP supplements long-term. Some people may suggest taking 5-HTP along with a supplement that increases the amount of dopamine in the body, such as l-tyrosine or l-dopa.
Other potential side effects of taking 5-HTP supplements include:
Before taking 5-HTP, it is vital to check with a doctor to ensure the supplement will not interfere with any medical conditions or medications.
5-HTP has been available as a prescription medication and an OTC supplement for several decades. During this time, no large-scale studies have yet concluded that the supplement may successfully treat any medical condition.
It is possible that taking 5-HTP could have some short-term benefits in promoting sleep and weight loss.
Taking 5-HTP long-term could deplete stores of other vital neurotransmitters. A person should talk to their doctor if they are thinking of taking 5-HTP. This will help ensure that it will not cause any adverse reactions.
People can purchase 5-HTP supplements in pharmacies, at health food stores, and online.