Effect of Alpha-S1-Casein Tryptic Hydrolysate and L-Theanine on Poor Sleep Quality: A Double Blind, Randomized Placebo-Controlled Crossover Trial

Abstract

This randomized, placebo-controlled, crossover and double-blind study investigates the effects of RLX2™ containing alpha-s1-casein tryptic hydrolysate and L-theanine in working adults affected by poor sleep quality. The supplement or placebo was randomly and blindly assigned to 39 subjects for four weeks and the changes in the subjective sleep assessment via the Pittsburgh Sleep Quality Index (PSQI), heart rate, blood pressure, salivary cortisol by high-performance liquid chromatography method and alpha power of awake electroencephalogram (EEG) were studied. The data were analyzed in two ways, by crossover and crossover summed up. The latter depicted that RLX2™ improved PSQI total score, sleep latency, sleep duration, sleep habitual efficiency, daytime dysfunction, and increased total and frontal alpha power significantly (p < 0.05). The supplement prolonged the total sleeping time by 45 min in the supplement receiving group compared to the placebo group (p < 0.001). However, only sleep duration and sleep habitual efficiency showed a profound effect in both analyses (p < 0.05). In conclusion, being given its beneficial effects without notable adverse events, it would be advantageous to use these nutraceutical ingredients to promote better sleep quality. Further studies with a larger number participants are warranted to support these findings.

Dietary supplementation with Lactium and L-theanine alleviates sleep disturbance in adults: a double-blind, randomized, placebo-controlled clinical study

“…Two safety indices were assessed during the examination visit and again 8 weeks after the intervention. Moreover, to overcome the uncertainty of treatment efficacy, the intervention period of this study was set to 8 weeks, at least twice as long as that used in previous studies ( 17 , 19 , 24 ) that investigated the short-term efficacy of the product. In addition, a study period of more than 8 weeks was established according to a previously-completed comparative study on Lactium and L-theanin ( 24 ).…”

“…The sample size was calculated as 40 (20 each in the experimental and control groups), considering a 10% dropout rate. In accordance with a previous study, the sample size was estimated based on the following statistical parameters: an assumed statistical power of 80%; a significance level (α) of 0.05 for two-sided, two-sample, equal variance t -tests; a difference of 2.4 in the amount of change in PSQI scores between the LTC-022 and placebo groups; and a standard deviation of 2.5 ( 24 ). A total of 43 participants were registered for screening.…”

A proprietary black cumin oil extract (Nigella sativa) (BlaQmax®) modulates stress-sleep-immunity axis safely: Randomized double-blind placebo-controlled study

“…Sample size calculation was performed using the G Power Statistical Software (3.1.9.7 Version, Franz Faul, University of Kiel, Kiel, Germany) ( 14 ). It was estimated that a total of 35 participants per group would be required, with an anticipated non-compliance or dropout rate of 20%, yielding 80% power, and 5% significance level.…”

The Role of Supplements and Over-the-Counter Products to Improve Sleep in Children: A Systematic Review

“…Halson et al in 2020 [40] carried out a double-blind, placebo-controlled crossover experimental study to investigate the effects of an optimized drink containing six ingredients (tart cherry juice, high GI CHO, α-lactalbumin, adenosine-5-monophosphate (5-AMP), valerian and theanine) on sleep quality, reporting a significant reduction in sleep onset latency. Thiagarajah et al [44], in a randomized, placebo-controlled, crossover and double-blind study, investigated the effects of alpha-s1-casein tryptic hydrolysate containing RLX2™ and L-theanine in 39 adults with poor sleep quality showing improvement in sleep latency, sleep duration (increased by 45 min), habitual sleep efficiency and daytime dysfunction. No adverse events were reported.…”