What Is 5-HTP & How Long Does It Take to Work?

5-HTP shows promise for both the brain and body.
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While searching for supplements to help for depression or migraines, you might come across a supplement called 5-HTP. It's an ​over-the-counter​ supplement that still needs more research before its effects on the body can be confirmed. If it does what some claim, it would be an impressive supplement.



5-HTP is a precursor to serotonin. Research is inconclusive on how long it takes to work.

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Tryptophan and Serotonin

5-HTP stands for 5-hydroxytryptophan. It's a derivative of tryptophan, which is an amino acid. Amino acids are the building blocks of protein, and there are 20 total. Tryptophan is the amino acid rumored to cause ​drowsiness​ during Thanksgiving dinner. It's found in high concentrations in turkey, which is where the rumor comes from.

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The proper name for tryptophan is L-tryptophan. In addition to turkey, it's found in eggs, cheese, yogurt and fish. Your body turns tryptophan into a B vitamin, called niacin. That's used to make ​serotonin​, which is a hormone that has a few responsibilities in your brain and body.

Serotonin acts in the brain as a ​neurotransmitter​. It's responsible for feelings of wellbeing, and it stabilizes your mood. It also helps regulate your sleep-wake cycle, telling your body when to sleep and when to wake up, according to the Hormone Health Network.

In the body, serotonin interacts with your vascular system. It tells your blood vessels when to narrow, explains an article from the National Cancer Institute. It also acts in the digestive system to aid digestion. There's even a link between a lack of serotonin and irritable bowel syndrome, according to an article from the Canadian Society of Intestinal Research.


Read more:Serotonin-Rich Foods

Serotonin and Mental Health

While there's some evidence that serotonin deficiency leads to depression, that theory has been largely overturned explains a June 2015 study published in World Psychiatry. However, there are a few reasons why serotonin is important for mental health.


Serotonin helps with learning and understanding, ​punishment vs. reward​, according to the study above. It helps in delayed gratification, which means passing up something desirable in the short term for something even better in the long term.

For example, it helps you pass up a piece of candy, even though it would taste good, because you know it's better for your health in the long term.


While it doesn't necessarily help with depression, serotonin can prevent you from thinking a continuous chain of negative thoughts. In other words, it keeps your mood ​more neutral.


With many roles in the body and brain, there's no doubt that serotonin is an important hormone. That's why a supplement that claims to raise your serotonin levels is intriguing.


5-HTP as a Supplement

5-HTP is a precursor for serotonin. Initially, tryptophan was used as a supplement for the same purpose, but it caused a small crisis according to an article from the National Poison Control Center. In 1989, a string of illnesses and even deaths were tied back to a toxic tryptophan supplement.

Instead of trying to remake tryptophan supplements, 5-HTP was created. As a supplement, it's unclear exactly how much it can do for your body, but there's some ​limited evidence​ that it can help your brain and body, similar to serotonin.


For weight loss, 5-HTP can help in the same way that serotonin can. When you're able to give up a short-term benefit like delicious food for the long-term benefit of weight loss, you have a better shot at dieting. The same reward pathway is a target of 5-HTP.

An article from Winchester Hospital examined four studies on HTP and found that subjects lost weight in almost all of the studies. The subjects who took 5-HTP were more likely to eat less food without even noticing. They also felt more satisfied after meals and didn't feel the need to eat more.


If you're having trouble sleeping, 5-HTP can help. An article from Mount Sinai Hospital says that there's some evidence that 5-HTP can help you sleep. That makes sense, since serotonin can help regulate sleep. The article also explains that the effect on sleep isn't immediate and can take ​six to 12 weeks​.

There's also limited evidence to show that 5-HTP can help with fibromyalgia, a pain disorder. Fibromyalgia causes pain in the body and can be linked to low serotonin levels. While it won't cure the disease, an article from the University of Michigan says that 100 milligrams of 5-HTP three times per day can help ease symptoms.


Read more:Signs of a Fibromyalgia Flare-Up

Not Enough Evidence for 5-HTP

There's no specific dosing guideline for 5-HTP since research is still limited. For that reason, it's also tough to say how long it will take to kick in. For each condition that it's been studied for, different methods have been used. Dosage of 5-HTP is different for each study, as well as the amount of time that the supplement is taken.

Since it's a supplement with limited research, you should ​be carefulwhen supplementing with 5-HTP. There are some claims that it can help with depression, but that research doesn't seem credible. In that case, you shouldn't take it to cure depression, unless ordered by your doctor.

All claims you see on 5-HTP products may be misleading. Until enough research is done to back current claims, supplement companies can continue to market benefits that ​may not be credible.

The Food and Drug Administration is responsible for evaluating the claims made on supplements, but the amount of control they have is limited. The FDA has guidelines for things you can and can't say on a supplement label.

A company isn't allowed to make ​unadulterated or dangerous claims​. The companies themselves are responsible for making sure labels are accurate. The FDA simply steps in if it feels that the label isn't up to standards. However, it doesn't necessarily review every supplement as it comes out.

That means you shouldn't trust the claims on your 5-HTP supplement, whether that means the dose to use or the amount of time to take the supplement. There's not enough credible scientific evidence to support the supplement yet, but there might be in the future.




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