Does Mouth Taping Actually Help You Sleep?

Opening

Dear reader, have you seen those videos on Instagram or YouTube lately of people sleeping with tape over their mouths? This trend, called “mouth taping,” has spread quite widely here in Korea too. It shows up in nearly every influencer’s “daily routine” video, and you can even find dedicated products at Olive Young, Korea’s popular beauty retailer.

The claim is simple. If you put medical tape over your lips before bed, you’re forced to breathe through your nose, which supposedly reduces snoring, improves sleep quality, eliminates bad breath, and even sharpens your jawline. The #mouthtaping hashtag has racked up over 200 million views on social media. Celebrities like Gwyneth Paltrow and Erling Haaland have publicly endorsed it. Is any of this true?

I decided to trace the scientific evidence behind this trend, and honestly, I was floored by what I found. Let me walk you through it.

What the Science Actually Says: 25 Years of Research, 213 Subjects

In May 2025, the journal PLOS ONE published the first systematic review¹ of mouth taping. A research team from the London School of Hygiene & Tropical Medicine and the University of Saskatchewan College of Medicine synthesized 25 years of research, from 1999 to 2024, following the PRISMA guidelines².

Let me give you the bottom line first. Of 120 papers screened, only 10 met the inclusion criteria. Total number of subjects across all studies: 213. Of the 6 studies that measured the Apnea-Hypopnea Index (AHI)³, only 2 showed statistically significant improvement.

Let’s unpack this a bit. A 2022 study from Chang Gung Memorial Hospital in Taiwan applied mouth taping to 20 patients with mild sleep apnea and found their snoring index and AHI roughly cut in half. Sounds promising so far, right? But there’s an important caveat: the subjects were limited to people with a BMI under 30 and mild sleep apnea, and the sample size was just 20. The research team itself warned that “this could be dangerous for patients with moderate to severe sleep apnea.”

What about the rest of the studies? A 2023 study published in Sleep and Breathing observed something interesting. Even with tape applied, many people were still breathing through their mouths. The researchers called this phenomenon “mouth puffing” — air leaking out through the cheeks even when the mouth itself is sealed by tape. In other words, taping the mouth often didn’t result in complete nasal breathing at all.

And critically, a randomized controlled trial on asthma patients found no significant effect from mouth taping whatsoever.