L-tryptophan
Synopsis of L-tryptophan
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.
L-tryptophan is used for these health conditions
Addictions (sugar or refined carbohydrates) (Scientific)
Anxiety (Scientific)
Anxiety Disorders (Scientific)
Apathy (Scientific)
Appetite (deficient) (Scientific)
Bulimia (Scientific)
Depression (Scientific)
Insomnia (Scientific)
Mood Swings (Scientific)
Nervous Exhaustion (Scientific)
Nervousness (Scientific)
Neurosis (Scientific)
Obsessive Compulsive Disorder (Scientific)
Post Partum Depression (Scientific)
Seasonal Affective Disorder (Scientific)
Sleep (restless and disturbed) (Scientific)
Stress (Scientific)
Sugar Cravings (Scientific)
L-tryptophan is used to support these body systems
Brain (Scientific)
Glandular System (Scientific)
Hypothalamus (Scientific)
Nerves (Scientific)
Pineal Gland (Scientific)
Serotonin (Scientific)
Specific Neurotransmitters (Scientific)
Products containing L-tryptophan
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
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