Glycine Improves Sleep Quality in Human Volunteers: Polysomnographic Evidence
Does Glycine Supplementation Actually Improve Sleep Quality?
Glycine supplementation significantly improves subjective sleep quality and reduces sleep onset time in human volunteers, this controlled clinical trial demonstrates using both subjective measures and objective polysomnographic recordings. Participants taking 3 grams of glycine before bedtime reported feeling more refreshed upon waking, experienced faster sleep onset, and showed improved sleep efficiency on polysomnographic measurements. The amino acid appears to work by facilitating the drop in core body temperature necessary for sleep initiation and by modulating neurotransmitter activity in sleep-promoting brain regions. This research provides scientific validation for glycine as a safe, natural sleep aid with measurable benefits on both subjective sleep experience and objective sleep architecture.