nathan

The most recent systematic review on this (PLOS ONE, 2025, 10 studies, 213 patients total) notes that every included study was rated poor methodological quality (Newcastle-Ottawa scale), and only 2 of the 10 studies showed a statistically significant improvement in the apnea-hypopnea index — and only in mild-apnea subgroups — with most others finding no difference. Nothing in this literature tests or confirms the post's specific claim ('breathing in nasty stuff' while sleeping mouth-open) — that's a fear-based line that sells the product more than it describes evidence. The more serious point is safety: 4 of the 10 studies in the review explicitly flag asphyxiation risk with nasal obstruction, and no official sleep-society guideline was found endorsing this practice for the general population — per Cleveland Clinic and CNN coverage, it remains a clinically unvalidated social-media trend, dangerous in particular for anyone with undiagnosed sleep apnea or a congested nose. Verdict: unproven for the claim itself, with a genuine safety caution that shouldn't be minimized.