5-HTP (5-Hydroxytryptophan) is a natural substance said to promote weight loss. In the body, 5-HTP occurs as a byproduct of L-tryptophan (a type of protein found in a number of foods). When used as a weight loss aid, 5-HTP is typically sourced from the seeds of the Griffonia simplicifolia plant.
Why Do People Use It For Weight Loss?
5-HTP is known to increase the production of serotonin in the brain and central nervous system. A type of neurotransmitter (a chemical responsible for carrying messages between nerve cells), serotonin helps regulate appetite. Therefore, proponents claim that consumption of 5-HTP can help promote weight loss by keeping your appetite in check and, in turn, reducing your food intake.
Benefits of 5-HTP
According to the National Institutes of Health (NIH), there is not yet enough scientific evidence to rate the effectiveness of taking 5-HTP supplements for weight loss or obesity. However, the NIH notes that some preliminary research indicates that 5-HTP may help curb appetite, decrease caloric intake, and reduce weight in obese people.
The available research includes an older study from 1992 published in the American Journal of Clinical Nutrition. For the study, 20 obese participants were randomly assigned to receive either 5-HTP or a placebo for two six-week periods. While no diet was prescribed in the first study period, a reduced-calorie diet was recommended for the second. Study results showed that members of the 5-HTP group experienced significant weight loss during both periods. In addition, members of the 5-HTP group had a reduction in carbohydrate intake and a tendency to experience satiety (a feeling of fullness) earlier on when eating.
In another study (published in the International Journal of Obesity and Related Metabolic Disorders in 1998), researchers found that 5-HTP significantly decreased daily intake of calories and reduced body weight in overweight adults with type 2 diabetes. The study involved 20 overweight adults with type 2 diabetes, nine of whom were given 5-HTP and 11 given a placebo.
There is a lack of more recent research on the effectiveness of 5-HTP in promoting weight loss.
Is 5-HTP Safe?
According to the NIH, use of 5-HTP supplements may be linked to eosinophilia-myalgia syndrome (EMS), a serious condition that causes extreme muscle tenderness and blood abnormalities.
In 1989 and 1990, there was an epidemic of EMS among people who had ingested L-tryptophan (a precursor to 5-HTP). Upon investigation, the epidemic was traced back to a single source and attributed to contamination resulting from inadequate purification coupled with a then newly introduced fermentation process. Although commercial production of 5-HTP does not use such fermentation processes, the NIH advises avoiding use of 5-HTP supplements until more is known about their safety.
In addition, taking 5-HTP in combination with certain medications may produce harmful effects. These medications include antidepressant drugs (such as Prozac and Zoloft), dextromethorphan (Robitussin DM, and others), and meperidine (Demerol). 5-HTP may also interact with a number of herbal supplements, including St. John's wort and S-adenosylmethionine.
Should You Use 5-HTP for Weight Loss?
Due to safety concerns, the NIH advises against taking 5-HTP in supplement form. In addition, there's little evidence to support the claim that 5-HTP supplements can support weight loss.
If you're considering the use of 5-HTP supplements for weight loss (or for any other health-related purpose), it's important to consult your care provider before starting your supplement regimen.
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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 Jul;22(7):648-54.
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