The rationale for mouth taping during sleep is to encourage breathing through the nose rather than through the mouth. In a new paper, Canadian researchers reviewed the scientific literature on mouth taping, searching for studies that mentioned terms such as “mouth breathing”, “mouth taping” and “sleep”. Eight studies looked at mouth taping, and two studies involved using a chin strap to keep the mouth shut. They did however note we need further high-quality evidence to better understand if mouth taping is safe and works. This review didn’t focus on any research relating to mouth taping for proposed improvements to mood, skin, digestion, sharper jaw lines and other things, so the researchers could not draw conclusions about the efficacy and safety of mouth taping for those purposes.