Tryptophan: Part of Alpha-lactalbumin’s Superpower? 

Alpha-lactalbumin is the main protein fraction in human milk and the second most abundant fraction in bovine milk. By utilizing advanced filtration and processing technologies, our NutriPRO™ Alpha-lactalbumin products contain more than twice the amount of alpha-lact as a standard whey protein. With this, comes an increased level of the essential amino acid, tryptophan. The alpha-lactalbumin fraction itself provides as much as 77% more tryptophan than standard whey protein¹. 

Tryptophan plays a key role in many metabolic functions and is a precursor to the neurotransmitter, serotonin (5-hydroxytryptamine), which is critical to sleep, mood, and appetite, among many other functions. Thus, it’s no surprise that it is considered in the management of depression and sleep disorders². Tryptophan supplementation has been reported in a recent review to decrease anxiety and increase positive mood in healthy individuals, although a reduction in aggressive feelings was not found³. The amount of tryptophan studied and shown to beneficially influence mood varies from 0.13g to 3g per day, on top of what would be consumed from a meal. This is easily achieved in small serve of alpha-enriched whey protein.  

The higher tryptophan level is likely part of the reason why alpha-lactalbumin has been shown in clinical trials to improve measures of sleep and morning wakefulness. For example, Markus et al, 2005, found that evening alpha-lactalbumin intake significantly increased plasma tryptophan levels before bedtime, and modestly but significantly​ reduced sleepiness the following morning⁴. They also reported improved brain-sustained attention processes, as shown by the number of errors on a cognitive test, the following morning. The differences were particularly clear in poor sleepers.​ 

More recently, the effect of alpha-lactalbumin was tested in female semi-professional rugby union players⁵. During 4 x one week blocks (to represent the different types of weeks the players experience), the players wore wrist actigraphy watches and had either an alpha-lac rich product or placebo every night, two hours before bedtime. Sleep onset latency was found to be significantly reduced in the alpha-lac group during the away game week and bye week (no competition game scheduled). 

With the increased level of sleep disorders and mental health challenges in the general population, many are turning to their diet to improve their overall health and wellbeing. Alpha-lactalbumin provides tryptophan alongside all the other essential amino acids as an easily digested, high quality protein.