L-tryptophan
Scientific names: L-2-amino-3-(indole-3-yl) propionic acid
Alternate names: L-Triptofano, L-Trypt, L-Tryptophane, Tryptophan
Actions: Neurological of tryptophan depletion, Sedative
Background
L-Tryptophan is an essential amino acid that is necessary for making proteins. It is naturally found in red meat, poultry, eggs, and dairy.
L-tryptophan is important for many organs in the body. L-tryptophan is not made by the body and must be consumed from the diet. After absorbing L-tryptophan from food, the body converts some of it to 5-HTP and then to serotonin. Serotonin is a hormone that transmits signals between nerve cells. Changes in serotonin levels in the brain can affect mood.
People use L-tryptophan for severe PMS symptoms, depression, insomnia, and many other conditions, but there is no good scientific evidence to support any of these uses.
L-tryptophan is important for many organs in the body. L-tryptophan is not made by the body and must be consumed from the diet. After absorbing L-tryptophan from food, the body converts some of it to 5-HTP and then to serotonin. Serotonin is a hormone that transmits signals between nerve cells. Changes in serotonin levels in the brain can affect mood.
People use L-tryptophan for severe PMS symptoms, depression, insomnia, and many other conditions, but there is no good scientific evidence to support any of these uses.
Safety Safety definitions
When taken by mouth: L-tryptophan occurs naturally in many foods, and is consumed as part of the diet. L-tryptophan supplements are possibly safe when taken for up to 3 weeks. L-tryptophan can cause some side effects such as drowsiness, stomach pain, vomiting, diarrhea, headache, blurry vision, and others.
In 1989, L-tryptophan was linked to cases of a neurological condition called eosinophilia-myalgia syndrome (EMS). But these cases might be due to contamination. About 95% of all EMS cases have been traced to L-tryptophan produced by a single manufacturer in Japan.
There isn't enough reliable information to know if L-tryptophan is safe when taken for more than 3 weeks.
Breast-feeding: There isn't enough reliable information to know if L-tryptophan is safe to use when breast-feeding. Stay on the safe side and stick to food amounts.
In 1989, L-tryptophan was linked to cases of a neurological condition called eosinophilia-myalgia syndrome (EMS). But these cases might be due to contamination. About 95% of all EMS cases have been traced to L-tryptophan produced by a single manufacturer in Japan.
There isn't enough reliable information to know if L-tryptophan is safe when taken for more than 3 weeks.
Special Precautions & Warnings:
Pregnancy: It is possibly unsafe to take L-tryptophan in amounts greater than those found in foods during pregnancy. It might harm the unborn child.Breast-feeding: There isn't enough reliable information to know if L-tryptophan is safe to use when breast-feeding. Stay on the safe side and stick to food amounts.
Effectiveness
NatMed Pro rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.
Possibly ineffective Effectiveness definitions
- Depression. Taking L-tryptophan by mouth doesn't seem to be beneficial in patients with depression. Also, it may increase the risk of side effects of some medications.
Dosing & administration
L-tryptophan supplements have most often been used by adults in doses of 60 mg by mouth daily for 16 weeks. Speak with a healthcare provider to find out what dose might be best for a specific condition.
Keep in mind that some dietary supplement products might not list L-tryptophan separately on the label. Instead, it might be listed under niacin. Niacin is measured in niacin equivalents (NE). 60 mg of L-tryptophan is the same as 1 mg NE.
Keep in mind that some dietary supplement products might not list L-tryptophan separately on the label. Instead, it might be listed under niacin. Niacin is measured in niacin equivalents (NE). 60 mg of L-tryptophan is the same as 1 mg NE.
Interactions with pharmaceuticals
Sedative medications (CNS depressants)
Interaction Rating=Major Do not take this combination.
L-tryptophan might cause sleepiness and slowed breathing. Some medications, called sedatives, can also cause sleepiness and slowed breathing. Taking L-tryptophan with sedative medications might cause breathing problems and/or too much sleepiness.
Serotonergic drugs
Interaction Rating=Moderate Be cautious with this combination.
L-tryptophan might increase a brain chemical called serotonin. Some medications also have this effect. Taking L-tryptophan along with these medications might increase serotonin too much. This might cause serious side effects including heart problems, seizures, and vomiting.
Interactions with herbs & supplements
Herbs and supplements with sedative properties: L-tryptophan might cause sleepiness and slowed breathing. Taking it along with other supplements with similar effects might cause too much sleepiness and/or slowed breathing in some people. Examples of supplements with this effect include hops, kava, melatonin, and valerian.
Herbs and supplements with serotonergic properties: L-tryptophan increases a brain chemical called serotonin. Taking it along with other supplements that have this effect might cause serious side effects, including heart problems, seizures, and vomiting. Examples of supplements with this effect include 5-HTP, black seed, SAMe, and St. John's wort.
Herbs and supplements with serotonergic properties: L-tryptophan increases a brain chemical called serotonin. Taking it along with other supplements that have this effect might cause serious side effects, including heart problems, seizures, and vomiting. Examples of supplements with this effect include 5-HTP, black seed, SAMe, and St. John's wort.
Interactions with foods
There are no known interactions with foods.
Products
View all productsPer tablet:
Practitioner product
Practitioner product
Per 7 g (Lemonade):
- L-tryptophan
- Schisandra chinensis ext. equiv. dry 2.5 g
- L-leucine
- L-isoleucine
- L-methionine
- L-threonine
- L-valine
- L-lysine
- L-phenylalanine
- L-histidine
- Calcium citrate
- Magnesium bisglycinate
- Flavour
- Silica - colloidal anhydrous
- Ascorbic acid (Vitamin C)
- Potassium citrate
- Pyridoxal 5-phosphate (P5P)
- Methylcobalamin (Activated B12)
- Stevia rebaubiana
420 g Lemonade
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Per serve (Rich Chocolate):
938 g Rich Chocolate
RRP: $89.95$80.96Save: 10%
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Per 12 g (Juicy Peach):
- Total Amino blend Amino9™ 2 g
- L-tryptophan
- L-leucine 2 g
- L-valine 1 g
- L-isoleucine 1 g
- L-histidine
- L-isoleucine
- L-leucine
- L-lysine
- L-methionine
- L-phenylalanine
- L-threonine
- L-valine
- L-glutamine 1 g
- Sodium chloride (Salt)
- Potassium chloride
- Calcium citrate
- Magnesium sulphate
- Ananas comosus (Bromelain) 25 mg
- Natural flavours
- Citric acid monohydrate
- Stevia rebaubiana
- Polyphenolic fulvic minerals 10 mg
- Tart cherry extract 250 mg
- Curcuma longa 50 mg
RRP: $69.99$61.59Save: 12%
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Per 30 g (Passionfruit):
- L-tryptophan
- Hydrolysed pea protein
- L-alanine
- Glycine
- L-valine
- L-leucine
- L-isoleucine
- L-proline
- L-phenylalanine
- L-tyrosine
- L-serine
- L-threonine
- L-methionine
- L-arginine
- L-histidine
- L-lysine
- L-aspartic acid
- L-glutamic acid
- L-cysteine
- Natural flavours
- Cichorium intybus (root) (Chicory)
- Acacia sp. (gum)
- Coconut water powder
- Medium chain triglycerides (MCT)
- Potassium citrate
- Magnesium citrate
- Sodium chloride (Salt)
- Calcium citrate
- Ascorbic acid (Vitamin C)
- Citric acid anhydrous
- Stevia rebaubiana
- Thaumatin
- Beta-carotene
- Riboflavin (Vitamin B2)
$59.95
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Per 33 g (Banana Ice-Cream):
RRP: $79.99$70.39Save: 12%
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RRP: $49.95$43.96Save: 12%
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RRP: $58.95$48.63Save: 18%
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Per 30 g (Vanilla Bean):
900 g Vanilla Bean
RRP: $74.94$61.83Save: 17%
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Per 48 g:
- Whey protein concentrate
- Whey protein isolate
- Soy lecithin
- Theobroma cacao (Cocoa powder)
- Medium Chain Triglycerides (powder) (MCT)
- Calcium phosphate dibasic
- Flavour
- Magnesium citrate
- Cyamopsis tetragonoloba (Guar gum)
- Calcium citrate
- Zinc gluconate
- Ascorbic acid (Vitamin C)
- Beta-carotene carotenoids (Vitamin A)
- Chromium chloride
- Ferrous fumarate
- d-alpha-Tocopheryl acetate
- Calcium pantothenate (Vitamin B5)
- Riboflavin (Vitamin B2)
- Sodium selenite
- Thiamine hydrochloride (Vitamin B1)
- Cyanocobalamin (Vitamin B12)
- Biotin
- Potassium iodide
- Sodium molybdate
- Niacinamide (Vitamin B3)
- Copper sulfate
- Manganese citrate
- Cholecalciferol
- Folic acid
- Pyridoxine hydrochloride (Vitamin B6)
RRP: $64.96$58.47Save: 10%
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1 kg Chocolate
RRP: $79.95$67.96Save: 15%
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Per 48 g:
- Whey protein concentrate
- Whey protein isolate
- Flavour
- Medium Chain Triglycerides (powder) (MCT)
- Calcium phosphate dibasic
- Magnesium citrate
- Cyamopsis tetragonoloba (Guar gum)
- Calcium citrate
- Zinc gluconate
- Ascorbic acid (Vitamin C)
- Beta-carotene carotenoids (Vitamin A)
- Chromium chloride
- Ferrous fumarate
- d-alpha-Tocopheryl acetate
- Niacinamide (Vitamin B3)
- Copper sulfate
- Magnesium citrate
- Cholecalciferol
- Folic acid
- Pyridoxine hydrochloride (Vitamin B6)
- Calcium pantothenate (Vitamin B5)
- Riboflavin (Vitamin B2)
- Sodium selenite
- Thiamine hydrochloride (Vitamin B1)
- Cyanocobalamin (Vitamin B12)
- Biotin
- Potassium iodide
- Sodium molybdate
- Soy lecithin
- Stevia rebaubiana
RRP: $64.96$58.47Save: 10%
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Per 30 g (Vanilla Cinnamon):
- Oryza sativa (Brown rice protein isolate)
- Cinnamomum spp.
- Natural flavours
- Stevia rebaubiana
- Vanilla planifolia (Vanilla bean)
RRP: $49.95$41.21Save: 17%
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Per 20 g (Vanilla):
- Oryza sativa (Brown rice protein fermented)
- L-lysine
- Natural vanilla flavour
- Stevia rebaubiana
- Cellulase
- Proteolytic enzymes
Practitioner product
Per 30 g (Cacao):
- Pea protein isolate 25.2 g
- Dunaliella salina equiv. beta-carotene 390 µg
- Aloe barbadensis 1 g
- Malpighia glabra equiv. vitamin C 50 mg
- d-alpha-Tocopheryl acid succinate 2.5 mg
- Natural chocolate flavour
- Stevia rebaubiana
- Thaumatin
- Luo Han Guo (fruit) ext. (Monk fruit)
RRP: $52.55$34.16Save: 35%
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Per 30 g (Vanilla Bean):
1 kg Vanilla Bean
RRP: $59.95$49.46Save: 17%
OOS at supplier
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Per 30 g (Vanilla Bean):
1 kg Vanilla Bean
RRP: $85.95$70.91Save: 17%
Sold out
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Due back 29/10
RRP: $85.95$70.91Save: 17%
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