Does mouth taping help you sleep better?

Mouth taping has only a handful of small studies behind it in total: two systematic reviews each included no more than 9 to 10 studies with a combined 213 participants. The results contradict each other on several points, and there are no large randomised trials to provide clarity. For healthy sleepers who simply want to sleep better, there is therefore hardly any evidence that mouth taping does anything.

In one specific group, people with mild obstructive sleep apnoea (in which the throat temporarily collapses during sleep), two small studies observed an improvement in apnoea measurements. How large that effect is, and whether it applies to everyone with sleep apnoea, is not clear. In people using CPAP therapy, small laboratory studies showed that mouth breathing can undermine the functioning of the mask, and that mouth taping can reverse that effect. That is interesting, but it applies only to that specific medical situation, not to the average sleeper.

The physiological reasoning behind mouth taping is not entirely made up: nasal breathing keeps the mucous membrane lining of the throat more moist and flexible, which slightly reduces the likelihood of airway collapse. That mechanism, however, has been studied in people who are awake, not during sleep. Whether the effect measured during the day is relevant at night is unknown.

The risks deserve explicit attention. If you have a blocked nose, mouth taping can be seriously dangerous. Studies excluded such people for good reason. Suffocation is not a theoretical risk but a real danger that is identified in the literature. Therefore, never use mouth taping if you cannot breathe freely through your nose. For asthma patients, mouth taping was examined in a randomised study involving 51 people and was found to have no effect whatsoever on symptoms or lung function. The popular claims on social media, such as more energy, better immunity or improved oral hygiene, have little to no scientific research behind them.