Is mouth taping safe to do every night?

For most healthy adults, yes — mouth taping is safe for nightly use. It promotes nasal breathing, which is how your body prefers to breathe during sleep. The key safety variable is the adhesive itself, not the act of taping. Look for tapes with medical-grade, certified adhesives (like ISO 10993-1) rather than generic ones. It's not recommended for people with nasal obstructions, untreated moderate-to-severe sleep apnea, or children. If you have concerns, talk to your doctor first.