Quick 5-HTP Summary Points
- 5-HTP is an amino acid that is used to make the compound Serotonin, which helps to regulate mood, appetite and sleep.
- The non-prescription sale of 5 HTP is illegal in most but not all parts of Australia.
- The amino acid Tryptophan is used to make 5-HTP in the body, so eating more dairy, meats, eggs and nuts can be an indirect method to increase 5-HTP.
- Due to its effects 5-HTP is often used to support weight loss and improved training capacity.
- Good alternatives to 5-HTP include sleep support supplements and fat burners.
What is 5-HTP?
5-HTP, or 5-hydroxytryptophan, is an amino acid which the body makes naturally from tryptophan, another amino acid which we ingest as part of the protein in food. It is a precursor to the neurotransmitter chemical Serotonin, often referred to as "the happiness chemical", which is an important regulator of mood, appetite and sleep.
The rate-limiting step in the conversion to Tryptophan to Serotonin is the hydroxylation of Tryptophan to 5-HTP. Supplementing directly with 5-HTP rather than Tryptophan is believed to be the most efficient way to increase brain Serotonin (1).
Along with other tryptophan supplements, the non-prescription sale of 5-HTP has been banned by the Australian Therapeutic Goods Administration due to a number of issues.
Where does 5-HTP come from?
5-HTP supplements are made using an extract from the seeds of Griffonia simplicifolia,a tree native to Africa (2). 5-HTP very rarely occurs naturally in what we eat, but tryptophan, from which 5-HTP is made in the body, is found in a variety of foods. The richest natural food sources include cheese, poultry, eggs, fish, nuts, soy, and various greens.
Benefits of 5-HTP
5-HTP is necessary for the proper functioning of your body. It is decarboxylated in the brain and liver to produce serotonin, a neurotransmitter. Serotonin is involved in the communication between nearly all of our 40 million brain cells, and is also found in large quantities in the cells of the gut, and in blood platelets. Because of its widespread distribution through the cells of the body, Serotonin is believed to have a large number of psychological and physiological effects. It has been used to treat conditions as diverse as obesity, depression, fibromyalgia, insomnia, and headaches, with varying success.
Benefits of 5-HTP for Bodybuilding
5-HTP is an aid to weight loss and a number of studies have found it to be an effective appetite supressant. 5-HTP is converted to serotonin, which then acts upon a region of the brain called the hypothalamus which regulates hunger. In experiments, people given 5-HTP supplements voluntarily decreased their calorie intake by as much as 38% (3,4,5).
A low energy intake can cause mood alteration, lethargy and a lack of mental alertness. These changes can impact negatively on the ability to reach fitness goals.
Serotonin has long been known to be related to depression, and many anti-depressant medications work by increasing the level of serotonin in the brain. For this reason, 5-HTP has developed a widespread reputation as a mood enhancer. (6)
Inadequate sleep is known to lead to decreased athletic performance (7). Serotonin is converted in the body to a hormone called Melatonin, which is know to have a strong influence on sleep patterns. Although there is little evidence of this in studies performed on healthy people, belief is widespread that 5-HTP can improve sleep quality
Side effects, safety concerns and negatives
Despite a reputation a s a mood enhancer and sleep aid, only a small amount of scientific evidence exists which supports 5-HTP's effectiveness. Many studies have returned inconclusive results.
At lower doses, 5-HTP is reported to cause minor side effects such as nausea, bloating, heartburn and headache.
At higher doses, or in combination with other medications, side effects can be quite serious. (8)
Serotonin syndrome (Serotonin toxicity) is caused by an excess of serotonin in the brain. It is most often caused by taking more than one Serotonin-enhancing substance at the same time, such as 5-HTP and an antidepressant medication. Symptoms range in severity according to the level of intoxication and may include increased heart rate, tremor, sweating, mental agitation, seizures, shock, organ failure and death (9).
5-HTP, along with other L-Tryptophan supplements, have been implicated in the flu-like, potentially fatal Eosinophilic Myalgia Syndrome. This syndrome was initially tied to impurities - Amino Acids called "Peak E" and "Peak X" - which were present in these products because of poor manufacturing processes by a single major supplier. Some people reject this idea and believe that the syndrome is caused by an excess of tryptophan itself (10, 11).
5-HTP Legal status
5-HTP at the time of writing is legal to import for personal use in minimal quantities, or available for retail purchase in a minority of states within Australia only.
Other supplements are available which have appetite supressant and mood enhancing effects similar to 5-HTP. These type of ingredients are often included, in optimal pre-formulated dosages in fat burners. Phenylethylamine is also another ingredient with mood enhancing potential that is often found in fat burners in place of 5-HTP. 5-HTP can be found in some sleep supplements, though in Australia they are replaced by ingredients such as GABA and phenibut.
Stacking with 5-HTP
It is best to allow a few hours between amino acids and other sources of protein. 5-HTP used to be stacked frequently with L-Tyrosine and other cognitive enhancers.
(1) Smith SA, Pogson CI. The metabolism of L-Tryptophan by isolated rat liver cells. Biochem J. 1980; 186: 977-986.
(2) Fellows Linda E, Bell E.A. 5-hydroxy-l-tryptophan, 5-hydroxytryptamine and l-tryptophan-5-hydroxylase in griffonia simplicifolia. Phytochemistry 1970; 9(11): 2389–2396
(3) Ceci F, Cangiano C, Cairella M, Cascino A, Del Ben M, Muscaritoli M, Sibilia L, Rossi Fanelli F. The effects of oral 5-hydroxytryptophan administration on feeding behavior in obese adult female subjects. J Neural Transm. 1989; 76(2): 109-17.
(4) Cangiano C, Laviano A, Del Ben M, Preziosa I, Angelico F, Cascino A, Rossi-Fanelli F. Effects of oral 5-hydroxy-tryptophan on energy intake and macronutrient selection in non-insulin dependent diabetic patients. Int J Obes Relat Metab Disord. 1998; 22(7): 648-54.
(5) Cangiano C, Ceci F, Cascino A, Del Ben M, Laviano A, Muscaritoli M, Antonucci F, Rossi-Fanelli F. Eating behavior and adherence to dietary prescriptions in obese adult subjects treated with 5-hydroxytryptophan. Am J Clin Nutr. 1992; 56(5): 863-7.
(6) Shaw K, Turner J, Del Mar C. Tryptophan and 5-hydroxytryptophan for depression. In Shaw, Kelly A. Cochrane Database of Systematic Reviews (Online) (2002) Accessed 29th October 2013.
(7) Skein M, Duffield R, Edge J, Short MJ, Mündel T. Intermittent-sprint performance and muscle glycogen after 30 h of sleep deprivation. Med Sci Sports Exerc. 2011; 43(7): 1301-11
(8) Byerley WF, Judd LL, Reimherr FW, Grosser BI. 5-Hydroxytryptophan: a review of its antidepressant efficiency and adverse effects. J Clin Psychopharmacol. 1987; 7(3): 127-37.
(9) Boyer, EW; Shannon, M. The Serotonin Syndrome. N Engl J Med. 2005; 352 (11): 1112–20
(10) Smith MJ, Garrett RH. A heretofore undisclosed crux of eosinophilia-myalgia syndrome: compromised histamine degradation. Inflamm. Res. 2005; 54 (11): 435–50.
(11) Preuss HG, Echard B, Talpur N, Funk KA, Bagchi D. Does 5-hydroxytryptophan cause acute and chronic toxic perturbations in rats? Toxicol Mech Methods. 2006;16(5):281-6.