An extract from asparagus improves sleep quality and reduces sleepiness and fatigue on awakening: A pilot randomized controlled trial
DOI:
https://doi.org/10.31989/ffhd.v15i4.1574Abstract
Background: Good sleep is essential for a healthy, active life that supports disease prevention. Sleep debts caused by sleep deprivation, irregular sleep, and insomnia increase the risk of metabolic syndrome, mood disorders, dementia, and cancer. Today's lifestyles in developed countries are prone to sleep debts, which has led to social interventions that aim to reduce sleep-related health problems. ETAS®50 is a standardized extract of Asparagus officinalis stem, and has been reported to improve sleep quality, maintain sleep rhythms, and relieve mental stress.
Methods: This pilot randomized, double-blind, placebo-controlled, crossover study was conducted in healthy adult males with sleep problems to evaluate the effects of ETAS®50 on sleep quality. Participants took ETAS®50 (300 mg/day) or placebo, and underwent an electroencephalogram, measured during sleep with a device known as the InSomnograf K2®. They were given a subjective assessment of sleep through a questionnaire known as the Oguri-Shirakawa-Azumi sleep inventory, specifically the Middle-Aged and Aged version (OSA-MA). Trial registration: the University Hospital Medical Information Network Clinical Trial Registry UMIN000052913.
Results: ETAS®50 showed a tendency to increase the ratio and total duration of Stage N3, known as the deepest stage in non-REM sleep (NREM). In addition, the subjective evaluation of sleep showed significant improvements in scores corresponding to tiredness upon rising, initiation and maintenance of sleep, refreshment after waking, and total scores. The total duration and ratio of Stage N3 are important indicators for assessing sleep quality. The favorable results suggested that dietary intake of ETAS®50 may improve sleep quality, enhancing subjective sleep assessment the next morning.
Conclusion: Supplementation of ETAS®50 may offer a practical approach to improving sleep quality.
Keywords: Sleep debts, electroencephalogram, ETAS®50, InSomnograf K2®
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