If you’re anything like the other 284 million people worldwide, you’ve probably experienced some semblance of anxiety in your life.

Nausea, headaches, sweating, shortness of breath, sweating, rapid heart and breathing rate, worry, fear, and dozens of other symptoms that can arise when a wave of anxiety decides it’s going to hit you across the face [1].

Anxiety is one of the most common mental disorders

It can be something that starts early in life and follows a chronic course. Unless you do something about it, that is.

Now, there’s the usual course that most people take courtesy of big pharma—Xanax, Valium, Ativan, Prozac, Zoloft, and beta-blockers.

Sound familiar?

They’re some of the most common medications prescribed to check your anxiety levels before they get out of hand.

But the problem with these drugs is that they’re not really solving the problem...

...they’re merely sweeping it under the rug by recycling neurotransmitters in your brain that regulate mood.

That’s how SSRIs work.

SSRIs keep serotonin flowing through your brain to keep your spirits up, but they’re not actually giving you more of it.

Alternatively, you can go the more natural route...

It's better to dig six feet down and find out what could really be causing your anxiety—neurotransmitters, or actually even lack thereof.

But if you’ve ever tried to deal with your anxiety without the help of meds, you’ve probably browsed the shelves of a good deal of health food stores for supplements to help you with anxiety.

Along the way, you’ve probably come across things like magnesium, 5-HTP, vitamin D, L-theanine, B vitamins, and maybe even valerian root.

They’re all great, but there’s one other that's missing and could be beneficial.

L-tryptophan can help with anxiety

Now you may think: “doesn’t tryptophan make you sleepy, how is that going to stop my anxiety?”

Yes, L-tryptophan definitely does induce sleep.

But that’s not all it does.

Super brief summary of L-tryptophan

Tryptophan is an essential amino acid that is the precursor for serotonin, your “happy hormone,” and also melatonin.

But since tryptophan is an essential amino acid, it can’t be synthesized by your body and therefore must be obtained exogenously (i.e. through food or supplements).

Luckily, the best supplements for sleep include L-tryptophan on its ingredients list to help keep your sleep cycles in check while also helping to manage your anxiety, as you'll find out in the following article.

Continue reading to find out how L-tryptophan helps combat anxiety in more detail...

It Boosts Your Levels of Serotonin

This may be the most critical function of tryptophan in alleviating anxiety.

A serotonin deficiency has one major significant impact on you: it makes your mood go somewhat AWOL.

By that, we mean increased susceptibility to depression, impulsive behaviours, aggression, insomnia, and so much more. But also, anxiety.

As we just mentioned, tryptophan is the precursor to the synthesis of serotonin. This conversion is a two-step process that highly depends on brain concentrations of tryptophan.

One mechanism on the role of serotonin (5-HT) in anxiety suggests that panic attacks occur because of spontaneous neuronal discharge in the area of the brain responsible for the activation of the fight-or-flight mechanism (our stress response).

Also, 5-HT (serotonin) inhibits this activity, thereby preventing the onset of a panic attack [2].

So, if your brain concentrations are low, your body won't synthesize enough serotonin, and your moods are going to suffer.

And because of the role of serotonin in mood and anxiety, low levels have been linked to increased anxiety and depression [2, 3].

Additionally, a study conducted in 2000 looked at the relationship between panic disorders and tryptophan.

It found that participants who lacked tryptophan supplementation had significant increases in anxiety, as well as neurovegetative symptoms. This suggests that tryptophan may exhibit a protective effect against anxiety [4].

It’s a Precursor for Melatonin

If there’s one hormone that packs a serious punch capable of knocking us out, it’s melatonin—and we literally mean knocks us out because melatonin is the hormone that controls your sleep-wake cycle.

But it also has roles in reproduction, the immune system, and digestion [5][5].

And it may be news to you, but high cortisol activates the stress response (remember fight-or-flight from before?), which can further induce feelings of anxiety.

By now you’re probably asking yourself how much is enough and where can you get it.

Tryptophan is widely available in food sources, mainly animal proteins and some plant-based sources.

Still, the problem with this is that it competes for absorption in the brain against larger amino acids like valine, isoleucine, leucine, tyrosine, phenylalanine, and methionine [6].

So, if plasma concentrations of these other amino acids are low, tryptophan absorption will be higher, but if the opposite is true, it decreases. Hence why even if we eat foods rich in tryptophan, it doesn’t really affect plasma concentrations all that much.

In this situation, what’s a person to do?

You turn to L-tryptophan supplements—the pure amino acid.

How much tryptophan do you need to check your anxiety and keep it locked away?

While there are no definitive dosages to help improve mood and reduce anxiety, studies show that doses of 4 to 5 g are safe for consumption with few side effects [7].

In one study conducted on the use of L-tryptophan for reducing side effects of smoking cessation, 50mg/kg daily appeared to reduce symptoms of anxiety [8].

Keep in mind that you may come across two forms of tryptophan: L-tryptophan and D-tryptophan, and they’re not to be confused.

The former is the amino acid used in protein synthesis that can cross the blood-brain barrier, while the latter is the isomeric form produced during food processing and by microbes [5, 9].

Also note that if you’re on medications for anxiety, L-tryptophan supplements can interact with these drugs, so we’d advise consulting with your healthcare professional before self-supplementing.


  1. R Shri. Anxiety: Causes and Management. The Journal of Behavioral Science. 2010; 5(1): 100-118.
  2. AC Pyle, SV Argyropoulos, DJ Nutt. The role of serotonin in panic: evidence from tryptophan depletion studies. Acta Neuropsychiatrica. 2004; 16: 79–84.
  3. R Hakkarainen, T Partonen, J Haukka, J Virtamo, D Albanes, J Lönnqvist. Association of dietary amino acids with low mood. Depression and Anxiety. 2003; 18(2), 89–94.
  4. K Schruers, T Klaassen, H Pols, T Overbeek, NE Deutz, E Griez. Effects of tryptophan depletion on carbon dioxide provoked panic in panic disorder patients. Psychiatry Res. 2000 Apr 10; 93(3):179-87.
  5. DM Richard, MA Dawes, CW Mathias, A Acheson, Hill-Kapturczak N, Dougherty DM. L-Tryptophan: Basic Metabolic Functions, Behavioral Research and Therapeutic Indications. Int J Tryptophan Res. 2009; 2: 45-60.
  6. E Höglund, O Overli, S Winberg. Tryptophan Metabolic Pathways and Brain Serotonergic Activity: A Comparative Review. Front. Endocrinol. 2019 April; 10: 158.
  7. JD Fernstrom. Effects and Side Effects Associated with the Non-Nutritional Use of Tryptophan by Humans. The Journal of Nutrition. 2012 Oct; 142(12): 2236-2244.
  8. DJ Bowen, B Spring, E Fox. Tryptophan and high-carbohydrate diets as adjuncts to smoking cessation therapy. J Behav Med. 1991 Apr; 14(2): 97-110.
  9. M Friedman. Analysis, Nutrition, and Health Benefits of Tryptophan. Int J Tryptophan Res. 2018; 11.