crossover
    2007

    Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes

    Yamadera W, Inagawa K, Chiba S, Bannai M, Takahashi M, Nakayama K

    Published in Sleep and Biological Rhythms

    Methodology

    Randomised double-blind crossover polysomnography study of 3 g glycine before bed in volunteers with insomnia tendencies

    Key Findings

    Glycine shortened latency to sleep onset and to slow-wave sleep without altering sleep architecture, alongside improved subjective sleep quality.

    Conclusions

    Glycine speeds sleep onset and improves perceived sleep quality with objective polysomnographic correlates.

    Limitations

    Very small sample; manufacturer-affiliated authors; single-night exposure.

    Supplements Studied

    Glycine
    Amino Acid

    Glycine ingestion before bedtime shortened the latency to sleep onset and to slow-wave sleep, with improved subjective sleep quality.

    Outcomes Measured

    Glycine shortened the latency to sleep onset and to slow-wave sleep.

    Glycine improved subjective sleep quality with polysomnographic shortening of sleep onset latency.

    Glycine shortened latency to sleep onset and to slow-wave sleep without altering sleep architecture, alongside improved subjective sleep quality.

    Related Health Concerns

    Study Details

    Year:2007
    Sample Size:11
    Duration:1 weeks
    Quality Score:5/10

    This information is for educational purposes only. Always consult a healthcare professional before starting any supplement regimen.