L-tryptophan

Other names

Free-Form L-Tryptophan
Tryptophan Capsules or Powder
Essential Amino Acid

Synopsis

L-Tryptophan is an essential amino acid, meaning the body cannot produce it and must obtain it from the diet. It plays a critical role in protein synthesis and is a precursor to several important bioactive compounds, including serotonin, melatonin, and niacin (vitamin B3). L-tryptophan is particularly well-known for its influence on mood regulation, sleep patterns, and appetite control.

As a precursor to serotonin, which is a neurotransmitter associated with mood, anxiety regulation, and well-being, L-tryptophan is often used to promote a sense of calm and to aid in the treatment of depression and anxiety. Once converted into serotonin, it also helps in the production of melatonin, a hormone that regulates sleep cycles. Due to these properties, L-tryptophan is commonly found in supplements aimed at improving sleep quality and mood stability.

In addition to its neurological effects, L-tryptophan is involved in protein metabolism, as it is incorporated into proteins, and helps the body synthesize vitamin B3 when needed, especially under low niacin conditions.

L-tryptophan is naturally found in protein-rich foods such as turkey, chicken, eggs, cheese, and legumes. It is also available as a dietary supplement and is commonly used to support sleep, mood, and cognitive function.

Historical Use
L-tryptophan has been studied since the early 20th century due to its crucial role in protein synthesis and its conversion into important neurotransmitters. Its link to serotonin was established in the 1950s, and since then, it has been explored for its effects on mood disorders, particularly depression and anxiety.

In traditional medicine, tryptophan-rich foods like turkey and dairy have long been associated with calming effects and improving sleep, though the specific role of L-tryptophan in neurotransmitter production was not fully understood until modern research into amino acids and neurochemistry.

L-tryptophan became widely used in clinical practice and alternative therapies in the 1970s and 1980s, particularly for sleep disorders and as a natural treatment for mild depression. It was used in nutritional supplementation to boost serotonin levels, improve sleep quality, and manage mood swings.

However, its use came under scrutiny in the late 1980s after an outbreak of eosinophilia-myalgia syndrome (EMS) in people who took L-tryptophan supplements, which led to the FDA temporarily banning its sale. The ban was lifted after it was found that a contaminated batch of the supplement was responsible, and the supplement has since been reformulated and reintroduced to the market.

Uses: Health Conditions

None

Body Systems

Brain (Science)
Glandular System (Science)
Parasympathetic Nervous System (Science)
Serotonin (Science)
Sympathetic Nervous System (Science)

Products containing this ingredient

Designs For Health Amino Acid Supreme™
Thorne Amino Complex Berry
Thorne Amino Complex Lemon
Pure Encapsulations Amino-NR
Pure Encapsulations Amino Replete
Metagenics BioPure Protein® Powder
Pure Encapsulations Cognitive Aminos
Pure Encapsulations Essential Aminos
Klean Athlete Klean Essential Aminos + HMB®
Klean Athlete Klean Isolate ™
Pure Encapsulations L-Tryptophan
Pure Encapsulations L-Tryptophan
Douglas Laboratories L-Tryptophan
Douglas Laboratories Muscle Protect™ with HMB®
Metagenics Perfect Protein® Pea & Rice Chocolate Powder
Metagenics Perfect Protein Pea & Rice Vanilla Powder
Metagenics Perfect Protein Whey Chocolate
Metagenics Perfect Protein Whey Vanilla
Thorne RecoveryPro NSF
Metagenics Ultra Glucose Control® Chocolate
Metagenics Ultra Glucose Control Chocolate
Metagenics Ultra Glucose Control Vanilla
Metagenics Ultra Glucose Control Vanilla
Metagenics UltraGI Replenish® Chocolate
Metagenics UltraGI Replenish Chocolate
Metagenics UltraGI Replenish Vanilla
Metagenics UltraGI Replenish Vanilla
Metagenics UltraInflamX Plus 360°® Chocolate/Orange
Metagenics UltraInflamX Plus 360° Mango
Metagenics UltraInflamX Plus 360° Mango
Metagenics UltraInflamX Plus 360° Orange
Metagenics UltraInflamX Plus 360° Original Spice
Metagenics UltraInflamX Plus 360° Pineapple/Banana
Metagenics UltraInflamX Plus 360° Pineapple/Banana
Metagenics UltraMeal Advanced Protein® Dutch Chocolate
Metagenics UltraMeal Advanced Protein French Vanilla
Metagenics UltraMeal Advanced Protein Plain
Metagenics UltraMeal Cardio 360°® Pea/Rice Chocolate
Metagenics UltraMeal Cardio 360° Pea/Rice Vanilla