Tryptophan is a type of essential amino acid, which means that the human body does not produce the substance. It must be obtained through dietary means. Some people may also choose to take tryptophan supplements, which are claimed to help with several conditions (such as depression, PMS, and ADHD). However, there are some safety concerns about using these supplements, such as the risk of a dangerous condition known as EMS.
Tryptophan (also known as L-tryptophan) is an essential amino acid. This means that humans must obtain tryptophan from dietary sources -- the body cannot produce it. Even though it is found in many foods, dietary supplements are also available. These supplements are claimed to be useful for treating a variety of conditions, such as depression, anxiety, premenstrual syndrome (PMS), and attention deficit hyperactivity disorder (ADHD).
(Click Benefits of Tryptophan for more information on what it is used for.)
Tryptophan is an amino acid, which is important for building proteins. The body also uses it to make serotonin, a neurotransmitter that plays an important role in depression and anxiety. The body also uses it to make niacin (a vitamin) and melatonin (a hormone).
Despite what you may read on the Internet, it is not currently "banned" by the Food and Drug Administration (FDA). For a while in the early 1990s, tryptophan supplements were banned in the United States due to safety concerns, but changes in the laws during 1994 allowed for the reintroduction of the supplements. According to one law, known as the Dietary Supplement Health and Education Act (DSHEA) of 1994, manufacturers of supplements do not need FDA approval before marketing their products and do not need to prove that their products are safe. This is why tryptophan supplements are once again available (it is not because they have ever been shown to be safe).