Taking 3 grams of glycine before bed might help people fall asleep faster and reach deep sleep quicker.
Scientific Claim
Glycine ingestion at 3 grams before bedtime is associated with reduced sleep latency to sleep onset and slow wave sleep in individuals with chronic sleep dissatisfaction, as measured by polysomnography.
Original Statement
“Glycine improved subjective sleep quality and sleep efficacy (sleep time/in-bed time), and shortened PSG latency both to sleep onset and to slow wave sleep without changes in the sleep architecture.”
Evidence Quality Assessment
Claim Status
overstated
Study Design Support
Design supports claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The abstract uses 'shortened' which implies causation, but the study's RCT classification has unclear randomization and blinding details per GRADE analysis, so definitive causal language is inappropriate. Association is the correct verb strength.
Evidence from Studies
No evidence studies found yet.