Battle of nootropics! L-tryptophan versus 5-HTP – which one is better?


L-tryptophan or 5-HTP? What to choose? This is a question you often ask! Both of these powerful dietary supplements are transformed into exactly the same neurotransmitters (serotonin and melatonin), responsible for providing us with a good mood and a peaceful sleep. L-tryptophan can exist as an amino acid in many types of food. 5-HTP, on the other hand, can only be taken as a dietary supplement.


In this article, we will examine the issue of L-tryptophan vs 5-HTP. We will look at how these substances work and we will try to assess which supplement is more effective. We will also check how safe it is to take both substances in one stack. To learn more - we invite you to read the rest of the article!

What is L-tryptophan?

L-tryptophan is an interesting amino acid with many unusual properties and advantages. It occurs naturally in food, especially in those with high protein content [1]. You can also get L-tryptophan from protein shakes or simply from commercially available supplements containing this substance. Although L-Tryptophan is absorbed from food, it is not easy to find it in such quantities that are high enough to experience the positive effects of its action. That's why we recommend including L-tryptophan supplements into your diet.

Trytophan chemical formulation
Trytophan chemical formulation

The benefits of using L-tryptophan

What is 5-HTP?

5-HTP is the next molecule in the conversion of L-tryptophan to serotonin and is a direct precursor of serotonin. Your body uses 5-HTP to produce serotonin. Then it uses serotonin to create melatonin in the pineal gland [3]. Effective melatonin production is sensitive to light and is directly responsible for the regulation of sleep.

Many people think that 5-HTP has really fast and powerful effects. An interesting thing about 5-HTP is that it is simply a modified version of L-tryptophan. Your body converts L-tryptophan into 5-HTP using a special enzyme [4].

5-HTP chemical formulation
5-HTP chemical formulation

The benefits of 5-HTP

  • suppresses appetite and provides energy,
  • improving mood
  • positively affects sleep

L-tryptophan versus 5-HTP

The dispute, which is better with supplements, has been going on for some time. Some users say that 5-HTP guarantees better results in terms of improving mood. Others, however, believe that L-tryptophan has a stronger effect on sleep regulation. Below are a few facts in that matter.

One of the things to consider when deciding L-Tryptophan or 5-HTP supplementation is that 5-HTP is so effective that your body can start to build tolerance after some time. This has not yet been proven by researchers, but theoretically can occur after long-term use of 5-HTP. L-tryptophan on the other hand, although more subtle in its effects, may be safer and healthier for long-term use. L-tryptophan supplements are also less likely to interact with drugs than 5-HTP.

Should you combine l-tryptophan with 5-HTP?

You can combine L-Tryptophan with 5-HTP, but you must use this combination in a responsible way. Both of these compounds increase the level of serotonin in the brain. Too much serotonin can cause many side effects, including potentially life-threatening serotonin syndrome [9].

Some consider L-Tryptophan a more subtle version of 5-HTP [10]. We recommend choosing one of two instead of using them together.

Safety of L-Tryptophan and 5-HTP

If you want to use 5-HTP or L-tryptophan, contact your GP if you are taking any prescription medication. It is particularly important to talk to your doctor if you are taking antidepressants or SSRIs (selective serotonin reuptake inhibitors).

SSRIs prevent the exhaustion of serotonin in the brain, which prevents depression. You should always use 5-HTP and L-tryptophan at the recommended doses.


In conclusion, 5-HTP and L-tryptophan are two great supplements that improve mood and help to sleep effectivelz and calmly. Your body transforms these two supplements into serotonin. However, the body must first convert L-tryptophan into 5-HTP before it can be used to make serotonin.

It is difficult to answer the question exactly which of the supplements is better. Each of them has its pluses. 5-HTP appears to be more efficient and faster in action, but L-tryptophan is safer and can be used longer.


  1. 7 Foods That Could Boost Your Serotonin, Written by Healthline Editorial Team

Medically Reviewed by Peggy Pletcher, MS, RD, LD, CDE on April 28, 2015

  1. L-Tryptophan Basic Metabolic Functions, Behavioral Research and Therapeutic Indications, DM Richard et al., Int J Tryptophan Res. 2009; 2 45-60, Published online 2009 Mar 23.
  2. The Pineal Gland and Melatonin, Endocrine Index, Colorado State University online notes, Last updated on March 17, 2003, Author R. Bowen
  3. Serotonin a la carte supplementation with the serotonin precursor 5-hydroxytryptophan, EH Turner et al., Pharmacol Ther. 2006 Mar; 109 (3) 325-38. Epub 2005 Jul 14.
  4. 5-HTP,, retrieved on 17 October 2016
  5. 5-HTP efficacy and contraindications, M Hinz, A Stein and T Uncini, Neuropsychiatr Dis Treat. 2012; 8 323-328, Published online 2012 Jul 19. doi 10.2147 / NDT.S33259
  6. 5-Hydroxytryptophan and clinically-effective serotonin precursor, TC Birdsall, Altern Med Rev. 1998 Aug; 3 (4) 271-80.
  7. The function of serotonin within the liver, Ruddell, Richard G. et al., Journal of Hepatology Volume 48 Issue 4 666 - 675
  8. Serotonin Syndrome, J Volpi-Abadie et al., Ochsner J. 2013 Winter; 13 (4) 533-540
  9. Difference between 5-HTP and L-Tryptophan, Thread on, retrieved on October 17, 2016


Tags: 5-htp, antidepressants, L-tryptophan, serotonin


  1. Avatar

    I had a pretty bad reaction taking 5-htp! I took 100 mg at bedtime and had really bad nightmares! I wonder if tryptophan is “milder” regarding these side effects? Thanks!!

    • David

      Hello Michael!

      Well, 5-HTP has better bioavailability, so tryptophan should be definitely milder. Yet take into account the other dosages of those two substances.

      Yet, if tryptophan will not do the trick try 5-HTP in a lower dosage. That nightmare thing could be not related to taking 5-HTP at all.

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