Other name(s):

a-amino-b-[3-indollyl]-propionic acid

Unsubstantiated claims

There may be benefits that have not yet been proven through research.

Tryptophan may make you sleepy. It’s been used to treat insomnia. It may be a natural antidepressant and stress reducer. It may help treat hyperactivity in children. It may also treat manic episodes in people with bipolar disorder. Tryptophan also decreases appetite.

Recommended intake

L-tryptophan is an amino acid that is naturally found in animal and plant foods. After eating foods with tryptophan, your body converts it into serotonin, vitamin B-6, and melatonin. It’s advised that no one take tryptophan as a supplement. This is because it may be unsafe. It can make some health conditions worse.

Side effects, toxicity, and interactions

The use of tryptophan has been linked with a condition that can be fatal. This is called eosinophilic myositis. It is also called eosinophilia-myalgia (EMS). This issue was linked to tryptophan made by a Japanese company that had recently changed its chemical processes. The cause of the condition has been debated. Most experts doubt that tryptophan itself caused the problem. Instead, they think it may have been caused by something else in the compound.

Ongoing studies have found that 4,5-tryptophan-dione is likely at fault for this problem. In a study of over-the-counter tryptophan, this chemical was found to make up 0.5% to 10.3% of the samples of tryptophan. The presence of this chemical in all samples means that tryptophan supplements aren’t safe to use.