• Jasmine Blake Hollywood, MS, HHP

L-Tryptophan for Insomnia: Regulate Your Sleep

What is Insomnia?

Insomnia is a condition that is explained as having a hard time falling asleep. [4].More often people associated this condition with not sleeping at all. Sometimes people are often associated with symptoms of waking earlier than normal which could be considered as maintain sleep, or excessive sleepiness or fatigue which could be considered non-restorative sleep. [4]. Sometimes insomnia can be without cause, meaning there is no psychiatric, medical, or environmental cause. There is no exact number to how many hours of sleep each person should get due to their bio-individual fingerprint [7], but experts try to recommend 7-9 hours per night for the average adult. [4]. Not one particular type that can be said is better than the other. Meaning, regeneration of the liver organ, the release of energy, and conversion of fat to muscle, along with regulation of sugar and free radicals are controlled during sleep.[4].

What can we do about it?

there are different types of interventions for insomnia because there are different types of insomnia that are experienced. Researchers say avoiding dietary stimulants is imperative, especially alcohol at night, coffee in the morning, recreational drugs, as well as over-the-counter and prescribed medications. [3]. However, regardless of the type of insomnia, L-Tryptophan is a great nutrient that can help reverse effects.

Intervention Instructions and Education

L-Tryptophan is an amino acid highly associated with the regulation of sleep and overall psychological functioning. It helps the body make particular proteins and helps with the overall functioning of the brain.  It can actually change into a chemical called serotonin. L Tryptophan is a precursor for serotonin and serotonin is a cofactor in insomnia. [3]. Tryptophan cannot be synthesized by the body either. Therefore Tryptophan is an essential amino acid.

Cofactors in the synthesis of serotonin are vitamins B6, B3, and magnesium. [3]. Therefore these two vitamins and minerals are essential in the production of L-Tryptophan in aiding in the treatment of insomnia. As well, L-Tryptophan is often regulated by insulin, therefore, glucose levels can affect the level of insomnia that a person experiences. [3]. Researchers state an appropriate recommended amount of L-Tryptophan for an individual experiencing insomnia should be around 2,000mg (2g). [2;3]. Although some studies say that 1-1.5g can be just as effective. [5].

The Sleep Questionnaire provided by the Institute of Functional Medicine, along with the Suggestions for Better Sleep PDF is highly recommended by other health practitioners. [6;9].The Suggestions for Better Sleep PDF gives clients tons of information about how to reduce stressors to enable better sleep cycles. [9]. The questionnaire is a great tool to assess where the lifestyle patterns intrude into the clients' life. [6].

L or D Tryptophan?

L-Tryptophan can be taken in supplementation form at 1-2g q.d. or can be eaten as a food. Nonetheless, Tryptophan itself should be taken with caution, especially when choosing supplements as there are two types of tryptophan:

  • L-tryptophan

  • D-tryptophan

The position of the molecule makes the difference.  D tryptophan is the isomer of L tryptophan. Although, D tryptophan is unable to convert into kynurenic acid, which is extremely important for neuro-activity. As L tryptophan is able to negate through the kynurenic pathway. [3].The kynurenic pathway is a protector of neuro pathways aiding as an inhibitor for the excitotoxic pathway. Thus enabling neuro-activity to give way and allow the brain to sleep.  Therefore, choosing L-Tryptophan is essential to treating insomnia.

L-Tryptophan Foods

Foods that can be integrated as supporters of L-Tryptophan are:

  • elk, roasted, (0.55g)

  • egg white, raw, (0.18g)

  • goat meat, cooked, (0.4g)

  • pork chop, cooked, (0.33)

  • haddock, cooked, (0.26)

  • blue crab, cooked, (0.25)

  • seaweed [spirulina], raw, (0.1g)

  • spinach leaf, raw, (0.1g)

(Table adapted from Cronometer Professional, 2019). [1].


  1. Ask The Oracle [Tryptophan]. (n.d.). Cronometer Professional. Retrieved from https://cronometer.com/pro/#foods (Links to an external site.)

  2. Demisch, K., Bauer., & J, Georgi, K. (1987). Treatment of severe chronic insomnia with L-tryptophan and varying sleeping times. Pharmacopsychiatry, 20(6):245-8. 

  3. Pizzorno, J., Murray, M., Joiner-Bey, H. (2016). The clinician’s handbook of natural medicine (3rd ed.). St. Louis, MO: Elsevier. 

  4. Ross, K. (2019). NUTR 636: Module 2 [Insomnia PDF]. Retrieved from Lecture Notes Online Web site: https://learn.muih.edu

  5. Schneider-Helmert, D. & Spinweber, C. L. (1986). Evaluation of L-tryptophan for treatment of insomnia: a review. Psychopharmacology, 89(1):1-7. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/3090582 (Links to an external site.)

  6. Sleep Questionnaire [PDF]. (2016). Institute for Functional Medicine. Retrieved from https://ifm.myabsorb.com/ (Links to an external site.)

  7. StressStopInc. (2013, May 28). Q & A with Dr. Rubin Naiman - sleep expert [Video File]. Retrieved from http://www.youtube.com/watch?v=qrluJLM_ePA (Links to an external site.)

  8. Stone, T. W. (2001). Kynurenic acid antagonists and kynurenine pathway inhibitors. Expert Opinion on Investigational Drugs, 10 (4):633-45. Retrieved from https://www.tandfonline.com/doi/abs/10.1517/13543784.10.4.633 (Links to an external site.)

  9. Suggestions for Better Sleep [PDF]. (2016). Institute for Functional Medicine. Retrieved from https://ifm.myabsorb.com/ (Links to an external site.)