L-Tryptophan is an essential amino acid. The body cannot synthesize it: it must be obtained from the diet. It functions as a metabolic precursor (i.e., substrate) for the synthesis of nicotinamide adenine dinucleotide (NAD), an important coenzyme found in all living cells—NAD is used for mitochondrial energy production and activation of the important sirtuin healthspan pathways. NAD can be made by any molecule which contains a niacin or nicotinamide (vitamin B3) molecule. L-Tryptophan is unique because it’s the only other way to build NAD that doesn’t start from vitamin B3. L-Tryptophan is also the precursor for the synthesis of the neurotransmitter serotonin and the neurohormone melatonin, which regulates sleep-wake cycles and nighttime body clock functions. In addition to these three main molecules, L-tryptophan is involved in making many other important intermediate molecules. Giving extra L-tryptophan allows the body to use it where it is needed most … at that time and over the next 12-16 hours. In general, giving extra L-tryptophan with breakfast supports both daytime mood (presumably via supporting serotonin function) and nightly sleep (presumably via supporting melatonin function). Giving some extra L-tryptophan also helps support body clock, orienting many of it’s daytime functions earlier in the day. L-tryptophan supplementation may support prosocial behaviors. Low-to-modest doses of L-tryptophan prior to bed may support healthier sleep cycles.
L-Tryptophan is used as a precursor (i.e., substrate) by the body to make NAD, serotonin, and melatonin. Our main reason for including it in a formulation would be to support biosynthesis of one or more of these important molecules.
In general, L-tryptophan is additive with other strategies for making NAD (such as the non-flushing form (niacinamide) and flushing form (niacin) of vitamin B3, so it can be useful to stack the two together in formulations.
L-Tryptophan sourcing is focused on identifying and purchasing from a reputable supplier and ensuring it is NON-GMO, gluten-free and vegan.
L-Tryptophan is generally considered to be dose-dependent (see Neurohacker Dosing Principles) in the range it’s commonly dosed (between several hundred mg to several grams or more a day). It’s been estimated that an average adult diet provides about 800-1000 mg/day of L-tryptophan. In studies that have looked at augmenting the breakfast meal with L-tryptophan, amounts less than the amount in an average diet have been sufficient to produce positive subjective responses during the day, with sleep that night, and with overall body clock function. When taken prior to bed, a dose close to ¼ the daily average intake has been sufficient to support healthier deep sleep. These studies are consistent with L-tryptophan supplementation supporting healthier function when given in amounts that are less than what would be found in an average diet.
Exercise performance (ergogenic effect)
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