correlational
Taking 3 grams of glycine before bed might help people who have trouble sleeping spend more time actually sleeping compared to time spent in bed
Scientific Claim
Glycine ingestion (3 g) before bedtime is associated with increased sleep efficacy (sleep time/in-bed time) in individuals with chronic sleep dissatisfaction
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 study uses 'improved' which implies causation, but the design is a non-randomized cohort study with unclear blinding and control group status. Only association can be claimed.
Evidence from Studies
No evidence studies found yet.