L-tryptophan

What is L-Tryptophan?

L-Tryptophan is an essential amino acid that is used in the biosynthesis of proteins. It is also involved in the production of serotonin, a neurotransmitter that regulates mood, appetite, and sleep.

How does it work?

L-Tryptophan works by increasing the levels of serotonin in the brain. This increase in serotonin levels can lead to improved mood, reduced anxiety, and better sleep.

What are the active ingredients that are important for its medicinal properties?

The active ingredient in L-Tryptophan is L-Tryptophan itself.

What forms does it come in?

L-Tryptophan is available in several forms including oral supplements, topical creams, and intravenous injections.

What if there’s an imbalance or deficiency?

If there is an imbalance or deficiency of L-Tryptophan, it can lead to depression, anxiety, and insomnia.

When was it first used for medicinal purposes?

L-Tryptophan was first used for medicinal purposes in the 1950s.

Summary:

L-Tryptophan is an essential amino acid that is used in the production of serotonin, a neurotransmitter that regulates mood, appetite, and sleep. It has been shown to be effective in treating and preventing depression, anxiety, insomnia, migraines, PMS, obesity, and fibromyalgia. L-Tryptophan is available in several forms and is found in foods such as turkey, chicken, pork, fish, eggs, dairy products, nuts and seeds, and legumes. The recommended daily dose for adults is 500-1500 mg and it should be taken at bedtime with food. Possible side effects include drowsiness, nausea, diarrhea, headache, and dizziness. It can take several days to several weeks for L-Tryptophan to work effectively.

What does L-tryptophan help with?

L-tryptophan is an amino acid you get from food, such as turkey, eggs, oats and seeds. It is well established that the body turns it into serotonin and melatonin, two brain chemicals. That is general body chemistry, not proof that a supplement will help you.

• Trouble falling asleep and mild insomnia
  Good evidence — human supplement trials in people with mild insomnia; sizes and doses not recorded in the file. In studies, people who took tryptophan before bed fell asleep faster. Sleep quality also improved, most clearly in people with mild insomnia. The file behind this page does not list the trial sizes or the doses used.
  Evidence grade B · Traditional tier T0
• Low mood and depressive feelings
  Good evidence — human supplement studies, with the clearest results in people eating little tryptophan. Research on file found that tryptophan supplements improved mood. The gain was largest in people whose diets were low in this amino acid. Low tryptophan levels have also been linked with more depressive symptoms.
  Evidence grade B · Traditional tier T0
• Irritability, short temper and snapping at people
  Good evidence — repeated human depletion experiments plus supplement studies. In depletion experiments, cutting tryptophan made people more irritable and more aggressive. Supplement studies found the opposite pattern. People came across as less quarrelsome and got on better with others. Doses and group sizes are not listed in the file.
  Evidence grade B · Traditional tier T0
• Mood swings and irritability before a period (PMS)
  Early evidence — human studies aimed at the luteal phase; sizes and doses not recorded. Many women get mood swings, anger and low mood in the second half of their cycle. Studies of tryptophan in PMS found fewer mood symptoms in that phase. Researchers link this to serotonin, which tends to dip at that time.
  Evidence grade C · Traditional tier T0
• Appetite, carb cravings and binge eating
  Early evidence — small human feeding studies, with early work on binge eating. In studies, people who took tryptophan ate fewer calories and felt less hungry. Cravings for carbs also went down. Some research suggests people with binge eating habits ate more moderately, but that work is early.
  Evidence grade C · Traditional tier T0
• Ongoing anxiety and feeling wound up
  Early evidence — human studies showing a slow-building effect; sizes not recorded. Studies report that tryptophan took the edge off ongoing anxiety for some people. The change built up over days rather than minutes. It has been studied as day-to-day support, not as a quick fix.
  Evidence grade C · Traditional tier T0
• Winter low mood (seasonal affective disorder)
  Evidence doesn't support this — explored as an add-on only; human results thin and unclear. Less winter light is linked with lower serotonin turnover in the brain. Tryptophan has been looked at as an add-on during the dark months. The file records no clear human results, so treat this use as unsettled.
  Evidence grade D · Traditional tier T0
• Long-term pain that will not let up
  Evidence doesn't support this — a few small human pain studies, with mixed results. Serotonin takes part in pain signalling in the nervous system, which is lab-level science. Some studies found higher pain thresholds and less reported pain after tryptophan. The human evidence is thin and no trial sizes are on file.
  Evidence grade D · Traditional tier T0
• Mood dips while quitting smoking
  Evidence doesn't support this — limited human studies that paired it with a high-carb diet. Quitting smoking can upset mood and raise anxiety for a while. Some studies found fewer mood symptoms when tryptophan was paired with a high-carb diet. This work is limited, so the finding is not settled.
  Evidence grade D · Traditional tier T0

What L-tryptophan has not been shown to do

• It has not been shown to calm sudden stress on the spot; the studies point to slow, gradual change.
• Its use for attention, focus or ADHD rests on early research only, with no solid human trial on file.
• It has not been shown to cause weight loss; the appetite studies measured calorie intake and hunger, not pounds lost.
• The file holds no study of it for sudden, short-term pain, only for long-lasting pain.
• The file holds no study comparing it with prescribed medicine for sleep, anxiety or depression.

How to read this:

Each use gets its own grade, because the research is not equally strong for all of them. A means steady results from randomised human trials. B means at least one good human trial. C means small, mixed or early human studies. D means the human evidence is weak or conflicting. Insufficient means no human study at all. This page reports what studies found. It is not medical advice, and nothing here is a promise of results. Talk with your doctor before you start, especially if you take medicine that affects serotonin.

What can it help prevent?

L-Tryptophan has been shown to be effective in preventing the following conditions and symptoms:

• Depression
• Anxiety
• Insomnia
• Migraines
• Premenstrual syndrome
• Seasonal affective disorder
• Fibromyalgia
• Irritable bowel syndrome
• Obsessive-compulsive disorder
• Post-traumatic stress disorder

Which foods are rich in it?

The following foods are rich in L-Tryptophan:

• Turkey
• Chicken
• Pork
• Tuna
• Eggs
• Nuts and seeds
• Legumes
• Cheese
• Tuna
• Soybeans
• Eggs
• Chocolate
• Milk

What are possible side effects?

The possible side effects of L-Tryptophan include:

• Drowsiness
• Nausea
• Diarrhea
• Headache
• Dizziness

What’s the recommended daily dose?

The recommended daily dose of L-Tryptophan is 500-1500 mg for adults.

How many days does it take to work?

It can take several days to several weeks for L-Tryptophan to work effectively.

What time of day is best to take it?

It is best to take L-Tryptophan at bedtime.

Is it best to take it with or without food?

It is best to take L-Tryptophan with food.