What is 5-HTP?
The human body produces 5-HTP from the amino acid tryptophan, found primarily in foods such as dairy products, poultry, and certain fish (e.g., tuna). (11) 5-HTP, in turn, may then be converted to serotonin and melatonin, neurotransmitters that play a part in regulating mood and sleep-wake cycles, among other effects. (7)
Serotonin is one of the primary mood regulators in the human brain.
5-HTP benefits
5-HTP has been clinically studied for a wide variety of health concerns, including depression and anxiety, insomnia, fibromyalgia, obesity, and Alzheimer’s disease and related dementias. However, the most extensively studied of these concerns is in the area of mood imbalances, including depression and anxiety.Depression and anxiety
For more than 40 years, 5-HTP and its precursor compound tryptophan have been clinically studied to evaluate their impact on anxiety and depression, often demonstrating highly encouraging results. While there is still a relative shortage of large-scale clinical trials, studies have repeatedly shown an improvement in mild to-moderate depression after supplementation with 5-HTP. (9) Regarding anxiety, studies show a similar level of improvement, with one study illustrating a moderate but statistically-significant reduction in anxiety as reported on a 90-item checklist. (5)Weight loss
While many people think of 5-HTP strictly for its role in mood support, there is also compelling research behind its use for promoting weight loss. A recent double-blind study showed that obese subjects who took a 5-HTP supplement reported weight loss, largely resulting from decreased appetite and corresponding food intake. (2)Fibromyalgia-related symptoms
Another area of research which can expect to receive further study involves the use of 5-HTP in fibromyalgia (FM) patients. Patients with FM commonly experience a wide range of symptoms, including:- Anxiety
- Fatigue
- Insomnia
- Muscular and joint pain and inflammation (3)
Some research indicates that 5-HTP supplements may improve symptoms associated with fibromyalgia, such as joint pain, insomnia, and anxiety.
Alzheimer’s disease and dementia
Several studies have shown conflicting data as to the role of 5-HTP in improving symptoms of Alzheimer’s disease and other dementias. However, one study theorized that symptom severity was linked with suspected malabsorption (and subsequent deficiency) of tryptophan. In the study, 23 subjects suffering from dementia were supplemented with 5-HTP to help alleviate a potential tryptophan deficiency. Subsequently, several patients whose tryptophan levels increased also experienced improved mental functioning, strongly warranting further exploration in this area. (6)Safety considerations and conflicting evidence
Despite an ongoing need for larger clinical trials, the above studies strongly point toward a number of areas in which 5-HTP may offer support. However, like all medicines, natural or pharmaceutical, it is imperative that 5-HTP is used in the appropriate manner and at the appropriate dosage. Your integrative healthcare provider can determine whether 5-HTP is appropriate for you.Serotonin syndrome
Since supplementation of 5-HTP can directly increase serotonin levels, it is important to take such supplements only as directed. Consuming too high a dose of 5-HTP or taking additional serotonin-boosting supplements or medications increases the risk of serotonin syndrome, a serious condition involving mental status changes as well as a number of nervous system impairments, leading to respiratory and cardiovascular issues if left untreated. (14) Commonly prescribed anti-anxiety and antidepressant medications, including selective serotonin reuptake inhibitors (SSRIs) and monoamine oxidase inhibitors (MAOIs), can raise serotonin levels by impeding its breakdown in the body. Simultaneously taking a supplement like 5-HTP may boost serotonin levels to an unsafe level. (10) Complicating matters further is a study showing that the deliberate combining of 5-HTP along with an SSRI was shown to improve depressive symptoms in patients receiving the anti-cancer/anti-viral drug interferon. Thus, the main takeaway from this section is that when there is a risk of serotonin syndrome, 5-HTP should be used with caution and with a health professional’s guidance. (13)Sleep disturbances
Despite the relative deficiency of clinical studies exploring 5-HTP’s impact on a variety of health concerns, the data regarding its impact on sleep is perhaps the most in need of further exploration. Animal studies have suggested that the complex biochemical interactions brought about through the use of 5-HTP may result in an initial decrease in sleep quality, that is soon followed by a steady improvement in gaining full, restful sleep. (4) While not explicitly exploring the impact of 5-HTP on insomnia, a separate study investigated the effects of 5-HTP supplementation on children who regularly experienced night terrors, showing a striking improvement in symptoms. (1) These varied, and seemingly conflicting, studies simply underscore the importance of continuing to research the effects of 5-HTP on sleep.The bottom line
After many years of research, we are still just scratching the surface of the multitude of health benefits offered through the use of 5-HTP supplements. Research has demonstrated significant improvements in mood, energy, body weight, cognitive wellness, pain and inflammation, and sleep, among many other benefits. However, during that time we have also gained an appreciation for the importance of safely using 5-HTP with the guidance of a qualified health provider. As with all health-related interventions, the best outcomes are generally yielded when the right intervention is given to the right individual, at the right dosage. If you’re a patient, speak to your integrative healthcare practitioner to determine if 5-HTP is right for your wellness plan.References
- Bruni, O., Ferri, R., Miano, S., Verrillo, E. (2004). L -5-Hydroxytryptophan treatment of sleep terrors in children. Eur J Pediatr. 163(7):402-407.
- Ceci, F., Cangiano, C., Cairella, M., et al. (1989)The effects of oral 5-hydroxytryptophan administration on feeding behavior in obese adult female subjects. J Neural Transm. 76(2):109-117.
- Centers for Disease Control and Prevention. (2020). Fibromyalgia. https://www.cdc.gov/arthritis/fibromyalgia/index.html
- Imeri, L., Mancia, M., Bianchi, S., Opp, M.R. (2000). 5-Hydroxytryptophan, but not L-tryptophan, alters sleep and brain temperature in rats. Neuroscience. 95(2):445-452.
- Kahn, R.S., Westenberg, H.G., Verhoeven, W.M., Gispen-de Wied, C.C., Kamerbeek, W.D. (1987). Effect of a serotonin precursor and uptake inhibitor in anxiety disorders; a double-blind comparison of 5-hydroxytryptophan, clomipramine and placebo. Int Clin Psychopharmacol. 2(1):33-45.
- Lehmann, J., Persson, S., Wålinder, J., Wallin, L. (1981). Tryptophan malabsorption in dementia. Improvement in certain cases after tryptophan therapy as indicated by mental behaviour and blood analysis. Acta Psychiatr Scand. 64(2):123-131.
- Maffei M. E. (2020). 5-Hydroxytryptophan (5-HTP): Natural occurrence, analysis, biosynthesis, biotechnology, physiology and toxicology. International journal of molecular sciences, 22(1), 181.
- MedlinePlus. (2021). 5-HTP. https://medlineplus.gov/druginfo/natural/794.html
- Meyers, S. (2000) Use of neurotransmitter precursors for treatment of depression. Altern Med Rev. 5(1):64-71.
- Patel, Y.A., Marzella, N. (2017). Dietary supplement-drug interaction-induced serotonin syndrome progressing to acute compartment syndrome. Am J Case Rep. 18:926-930.
- Richard, D.M., Dawes, M.A., Mathias, C.W., Acheson, A., Hill-Kapturczak, N., Dougherty, D.M. (2009). L-tryptophan: basic metabolic functions, behavioral research and therapeutic indications. Int J Tryptophan Res. 2:45-60.
- Sarzi Puttini, P., Caruso, I. (1992). Primary fibromyalgia syndrome and 5-hydroxy-L-tryptophan: a 90-day open study. J Int Med Res. 20(2):182-189.
- Turner, E.H., Blackwell, A.D. (2005). 5-Hydroxytryptophan plus SSRIs for interferon-induced depression: synergistic mechanisms for normalizing synaptic serotonin. Med Hypotheses. 65(1):138-144.
- Volpi-Abadie, J., Kaye, A.M., Kaye, A.D. (2013). Serotonin syndrome. Ochsner J. 13(4):533-540.