By Dr. Nikol Fedin, DMD — Co-founder of SayLess
Full transparency: I’m a licensed cosmetic dentist and I co-founded SayLess, so I have skin in the game here — literally. I built Night Lips because I couldn’t find a mouth tape I’d actually recommend to my patients. Read this knowing that context, and judge the information on its merits.
Every night, you cleanse, tone, layer your serums, press in your eye cream, and finish with a rich moisturizer. You’ve curated your routine down to the last drop. And then you fall asleep — mouth open — and quietly undo a significant portion of what you just did.
I say this as a dentist, and as someone who used to do exactly the same thing.
Mouth breathing during sleep is one of the most overlooked causes of accelerated skin aging, chronic dry mouth, disrupted sleep quality, and jawline loss of definition. Mouth breathing during sleep is far more common than most people realize — and most people have no idea it’s happening to them. Research published in the European Respiratory Journal found that mouth breathing increases upper airway resistance 2.5 times compared to nasal breathing, fragmenting sleep and pulling the brain repeatedly out of deep restorative stages.
That’s why I co-founded SayLess and created Night Lips. But before I tell you about the product, let me tell you what’s actually happening to your skin while you sleep with your mouth open.
What Mouth Breathing Does to Your Sleep Quality and Skin Overnight
Your skin does its most important repair work while you sleep. Cell turnover accelerates. Collagen synthesis peaks. Every product you applied before bed gets absorbed. This is the window your skincare routine is designed for.
Mouth breathing disrupts all of it — in two ways.
First, dehydration. When you breathe through your mouth, you lose significantly more moisture overnight than nasal breathers. Mouth breathing increases overnight water loss by approximately 42% compared to nasal breathing — your body loses significantly more moisture through oral expiration than nasal expiration. Research suggests this triggers compensatory fluid retention pathways, and combined with impaired sinus drainage and elevated cortisol from disrupted sleep, may contribute to the puffiness and tiredness many mouth breathers report waking up with. The expensive hydrating serum you applied at 10pm is fighting an uphill battle against the moisture your open mouth is pulling out of your system all night.
Second, inflammation. Mouth breathing bypasses your nasal passages, which are designed to filter, humidify, and regulate the air entering your body. Without that filtration, you’re drawing unfiltered, drier air directly into your throat and lungs. Over time, research shows that chronic mouth breathing disrupts the oral microbiome by eliminating the protective salivary buffer, creating an environment where pro-inflammatory pathogens thrive and triggering a systemic inflammatory response that raises markers like CRP and IL-6. The dermatology and geroscience literature has a term for the result: inflammaging — the chronic, low-grade systemic inflammation that accelerates biological aging. Research published in the Annals of the New York Academy of Sciences established that this persistent inflammatory state drives tissue degradation at the molecular level, triggering enzymes that break down collagen and elastin in the skin. A 2025 review in Frontiers in Immunology connects these same inflammatory pathways directly to accelerated visible skin aging.
As a dentist, I see the downstream effects of mouth breathing every day: dry cracked lips, accelerated tooth decay from dry mouth, worn enamel from nighttime grinding, and loss of jawline definition from years of sleeping with the jaw hanging open. The mouth is the gateway to the rest of the body, and what happens there at night matters far more than most people realize.
Why Nasal Breathing Changes Everything
Nasal breathing is the way your body was designed to breathe. Your nasal passages produce nitric oxide — a molecule that improves circulation, supports your immune system, and helps regulate blood pressure. None of this happens when you breathe through your mouth.
Research published in Acta Physiologica Scandinavica shows that nasal nitric oxide acts as a natural pulmonary vasodilator, improving oxygen delivery to the lungs by approximately 10% compared to mouth breathing. A separate study published in Thorax demonstrated that nasal nitric oxide also functions as a broad-spectrum antimicrobial agent, directly inhibiting bacteria and viral replication in the upper airway. And a 2023 randomized trial in the American Journal of Physiology found that just five minutes of nasal breathing measurably lowered diastolic blood pressure and shifted the nervous system toward a parasympathetic state.
During sleep specifically, nasal breathing keeps your jaw in its natural closed resting position. This engages and maintains the muscles that define your jawline. Over years of mouth breathing, those muscles weaken and the lower face gradually loses its structure — not from weight gain, not from aging alone, but from a mechanical pattern that nobody ever told you about.
Nasal breathing also supports deeper, more restorative sleep. When your airway is properly humidified and filtered, your body can reach the deeper sleep stages where physical and cognitive repair happens. This is why sleep specialist Dr. Michael Breus — one of the leading voices in sleep science — has been vocal about the importance of nasal breathing during sleep. Better breathing, better sleep, better recovery. It really is that connected.
How to Add Mouth Tape to Your Nighttime Skincare Routine
This is where I want to be practical with you, because the question I hear most from women is: does mouth tape work with my skincare routine, or do I have to choose?
You don’t have to choose. Here’s exactly how to integrate it.
Step 1: Cleanse Start with your usual double cleanse or single cleanse depending on your routine. Nothing changes here.
Step 2: Treatments and serums Apply your actives — retinol, vitamin C, peptides, whatever your routine calls for. Apply to your face and neck as usual. Let them absorb fully before moving to the next step.
Step 3: Moisturizer This is where most mouth tapes fail. A traditional adhesive strip will slide right off over moisturizer, or pull at your skin when you remove it in the morning. Night Lips was specifically formulated with a skin-safe, hypoallergenic adhesive that holds through moisturizer, serum, and overnight cream — and removes gently in the morning. It was designed with sensitive skin in mind.
Apply your moisturizer. Let it sink in for a minute or two.
Step 4: Lip care Apply your lip balm, lip mask, or overnight lip treatment. Night Lips holds over lip products — this was one of the non-negotiables when we were developing the formula. Your lips are covered by the tape all night. They should be hydrated, not stripped.
Step 5: Apply Night Lips Night Lips is cut in a lip shape — not a strip across the mouth — which means it sits naturally on your lips without covering your full face or feeling claustrophobic. The silky, ultra-breathable fabric means you barely feel it’s there. Press it gently into place and you’re done.
Step 6: Any remaining steps Eye cream, face oil, hair mask — whatever comes last in your routine, apply as normal. Night Lips doesn’t interfere with anything else you’re doing.
That’s it. The whole integration takes less than thirty seconds and you wake up with none of the dry mouth, puffiness, or morning grogginess that comes with a night of mouth breathing.
A Note on What’s Actually Touching Your Face
When I was developing Night Lips, one of the things I kept coming back to was the fact that most mouth tape on the market ships directly from overseas factories, sealed in plastic pouches. The chemical smell when you open the package is off-gassing from the adhesive — and you’re placing that tape directly under your nose, against your lips, for eight hours.
As a dentist who thinks carefully about what goes in and on the body, that wasn’t acceptable to me.
Night Lips is made from an ultra-breathable fabric with a skin-safe, hypoallergenic adhesive formulated for sensitive skin. We hand-package every single order in-house and aerate every tape before it ships — so when you open the pouch, there’s no chemical smell. Just clean, breathable fabric ready to use on night one.
WIRED named Night Lips the best mouth tape on the market, and I’m proud of that — but what I’m proudest of is that I’d put this on my own face every night without hesitation. Because I do.
Who This Is For
Night Lips is for anyone who wakes up with a dry mouth, anyone whose partner has mentioned snoring, anyone who feels like they slept but still wakes up tired, and anyone who has invested in their skincare routine and wants to make sure it’s actually working.
It’s also for anyone who is simply curious. The shift from mouth breathing to nasal breathing during sleep is one of the highest-leverage changes you can make for your health, your skin, and your sleep quality — and it costs less than a single serum.
If you’ve never tried mouth tape before, Night Lips is the place to start. The beginner-friendly Mini version covers just the center of the lips for those who want to ease in gradually. The full Night Lips tape provides complete coverage for deeper nasal breathing throughout the night.
The Moment Is Now
Mouth tape for sleep has become one of the most searched wellness topics of the last two years — and for good reason. The science of nasal breathing during sleep is no longer fringe. It’s backed by sleep specialists, recommended by dentists, and now a staple in the routines of people who take recovery seriously. Night Lips was built for exactly this moment.
Ready to Try It?
Your nighttime routine deserves a final step that actually protects everything else you’re doing. Night Lips takes thirty seconds to apply and works with every product already in your routine.
Shop Night Lips: https://getsayless.com/products/mouth-tape
30 strips per pack. One month to find out what better sleep and nasal breathing can do for you.
Dr. Nikol Fedin, DMD is a cosmetic dentist and co-founder of SayLess. Night Lips was developed from her clinical experience and her own nighttime routine.
References
Lee, Y.C., et al. (2022). The Impact of Mouth-Taping in Mouth-Breathers with Mild Obstructive Sleep Apnea: A Preliminary Study. Healthcare, 10(9), 1755. https://pmc.ncbi.nlm.nih.gov/articles/PMC9003800/
Fitzpatrick, M.F., McLean, H., Urton, A.M., Tan, A., O’Donnell, D., & Driver, H.S. (2003). Effect of nasal or oral breathing route on upper airway resistance during sleep. European Respiratory Journal, 22(5), 827—832. https://publications.ersnet.org/content/erj/22/5/827
Franceschi, C., Bonafe, M., Valensin, S., Olivieri, F., De Luca, M., Ottaviani, E., & De Benedictis, G. (2000). Inflamm-aging: An evolutionary perspective on immunosenescence. Annals of the New York Academy of Sciences, 908, 244—254. https://pubmed.ncbi.nlm.nih.gov/10911963/
Karpuzoglu, E., Holladay, S.D., & Gogal, R.M. Jr. (2025). Inflammaging: triggers, molecular mechanisms, immunological consequences, sex differences, and cutaneous manifestations. Frontiers in Immunology. https://pmc.ncbi.nlm.nih.gov/articles/PMC11893255/
de Souza, B.C. (2017). The quality of sleep modified by the mouth breathing syndrome can impair the athlete’s physical performance. Medicine. https://pdfs.semanticscholar.org/d5c5/f42b6109e3e5ce012f4f1dc6ed6f8de2dd7b.pdf
Lundberg, J.O.N. (1996). Inhalation of nasally derived nitric oxide modulates pulmonary function in humans. Acta Physiologica Scandinavica, 158, 343—347. https://stacks.cdc.gov/view/cdc/11642
Lundberg, J.O.N. (1999). Nasal nitric oxide in man. Thorax, 54, 947—952. https://publications.ersnet.org/content/erj/13/1/179
Watso, J.C., Cuba, J.N., Boutwell, S.L., Moss, J.E., Bowerfind, A.K., Fernandez, I.M., Cassette, J.M., May, A.M., & Kirk, K.F. (2023). Acute nasal breathing lowers diastolic blood pressure and increases parasympathetic contributions to heart rate variability in young adults. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 325(6). https://journals.physiology.org/doi/10.1152/ajpregu.00148.2023
Disclaimer
The information in this article is provided for educational purposes only and does not constitute medical or dental advice. Dr. Nikol Fedin, DMD, is a licensed cosmetic dentist and co-founder of SayLess. Her content reflects her professional knowledge and personal experience. It is not a substitute for advice from your own dentist, physician, or licensed healthcare provider. Individual results vary. If you have a medical condition including sleep apnea, respiratory conditions, or other health concerns, consult your physician before using mouth tape.
