Does Mewing Actually Work? An Honest Evidence Review

What Is Mewing?

Mewing is the popular name for a tongue posture technique promoted by British orthodontist Dr. John Mew and his son Dr. Mike Mew. The term comes from their surname and gained massive traction on social media platforms starting around 2019, though the underlying ideas have been circulating in niche orthodontic circles for decades.

Dr. John Mew developed a field he called orthotropics, which focuses on guiding facial growth through oral posture rather than relying on traditional braces or extractions. The central claim is straightforward: the way you rest your tongue, the way you breathe, and the way you swallow all influence how your face develops over time. According to orthotropic theory, modern humans have progressively worse facial development because of soft diets, mouth breathing, and poor oral posture habits established in childhood.

The basic practice involves resting the entire tongue flat against the roof of the mouth, keeping the lips sealed, breathing through the nose, and maintaining teeth in light contact. Proponents claim this can widen the palate, bring the maxilla (upper jaw) forward, and create a more defined jawline and cheekbone structure. The internet is filled with dramatic "mewing before and after" photos that appear to show significant facial changes. But how much of this holds up under scrutiny?

The Claimed Mechanism

The proposed mechanism behind mewing rests on a biomechanical argument. When the tongue is pressed firmly against the hard palate, it creates a constant, gentle force on the maxilla. Over time, this force is said to stimulate bone remodeling — expanding the palate laterally and encouraging the midface to grow forward rather than dropping downward. This concept is sometimes described as achieving "forward facial growth."

There are several components to the full orthotropic protocol:

• Tongue posture: The entire tongue, including the posterior third, should rest against the palate. This is the primary force driver.
• Correct swallowing: Instead of pushing the tongue forward against the teeth when swallowing (known as a tongue thrust), the tongue should press upward against the palate. A proper swallow involves the tongue pushing food backward with a wave-like motion against the roof of the mouth.
• Nasal breathing: Breathing through the nose keeps the mouth closed and the tongue in its proper resting position. Mouth breathing, by contrast, causes the tongue to drop to the floor of the mouth and the jaw to hang open, which proponents argue leads to elongated facial development over time.
• Lip seal: Keeping the lips gently closed at rest without straining reinforces the whole system and prevents mouth breathing.

The theory draws loosely from Wolff's Law, a well-established principle in orthopedic medicine that states bones adapt to the mechanical loads placed upon them. The question is whether the gentle force of a tongue against the palate is sufficient to drive meaningful skeletal change — particularly in adults.

What Does the Evidence Say?

Here is where honesty matters. If you are searching for "does mewing work" hoping to find a clear scientific consensus, you will be disappointed — not because the answer is definitively no, but because the research simply has not been done at the standard we would need.

There are no randomized controlled trials studying mewing specifically. The Mews' published case studies are largely observational, involve small sample sizes, and have not been peer-reviewed in high-impact orthodontic journals. Dr. John Mew was struck off the UK General Dental Council register in 2017 for bringing the profession into disrepute, though his supporters argue this was politically motivated rather than a reflection of the science.

The British Orthodontic Society (BOS) has publicly stated that there is no credible scientific evidence that mewing can change facial structure. Their position is that orthotropic claims lack the rigorous evidence base required to be considered an effective treatment. This is the stance of the mainstream orthodontic establishment.

That said, the picture is not entirely blank. There is legitimate orthodontic and craniofacial literature that touches on related concepts:

• Studies on mouth breathing in children consistently show it is associated with elongated facial development, narrow palates, and malocclusion. Correcting mouth breathing in growing children has been shown to improve facial development outcomes.
• Research on tongue posture and palatal expansion in pediatric patients shows that tongue position does influence palate width during growth. Myofunctional therapy, which overlaps significantly with mewing principles, is a recognized treatment in speech pathology and pediatric dentistry.
• Some orthodontic studies on functional appliances — devices that reposition the tongue and jaw — show measurable skeletal changes in growing children, supporting the idea that sustained forces can influence facial bone development during growth periods.

The gap in the evidence is not whether tongue posture matters during development — it almost certainly does. The gap is whether consciously changing tongue posture as an adult produces meaningful skeletal changes. On that specific question, the evidence is essentially nonexistent.

Age Matters: Children vs. Adults

This is the most important distinction in the entire mewing conversation, and it is often glossed over online. The age at which you start matters enormously because of basic craniofacial biology.

In children and adolescents, the bones of the skull and face are still growing. The palatal suture — the joint that runs down the middle of the roof of the mouth — remains open and responsive to mechanical forces throughout childhood and adolescence. This is why orthodontic palatal expanders work so well in young patients: the bones are literally being pushed apart at the suture, and new bone fills the gap.

For children who are mouth breathers or have poor tongue posture, correcting these habits early can plausibly influence how the face develops. This is not controversial — it aligns with mainstream orthodontic understanding of functional influences on growth. Pediatric myofunctional therapy is an established practice, and its principles overlap substantially with what mewing advocates recommend.

Adults are a different story. The cranial sutures progressively fuse throughout the late teens and twenties, with the palatal suture typically closing by around age 25 (though this varies). Once the sutures are fused, the maxilla is a single, rigid bone. The gentle force of a tongue pressing against the palate is orders of magnitude weaker than what would be required to move fused bone — surgically assisted rapid palatal expansion (SARPE) requires cutting through the suture with a saw to achieve expansion in adults.

This does not mean mewing is entirely useless for adults. There are soft tissue and postural changes that can occur at any age. But the dramatic skeletal transformations shown in many viral mewing before and after posts are almost certainly not happening in adults through tongue posture alone.

Proper Mewing Technique

Regardless of the debate about skeletal effects, the tongue posture and breathing habits promoted by mewing are generally considered healthy defaults by dental and medical professionals. If you want to practice proper oral posture, here is the correct technique:

The Basic Position

1. Place the entire tongue against the palate. This is the most commonly misunderstood part. Many beginners only press the tip of the tongue to the roof of the mouth. The key is to get the posterior third — the back of the tongue — up against the soft palate as well. Think of it as suctioning your whole tongue to the roof of your mouth.
2. Keep your lips gently sealed. Your lips should be together without straining. If your chin dimples or your mentalis muscle engages, you are forcing it.
3. Teeth in light contact or very slightly apart. You should not be clenching. A light touch or a millimeter of space is fine.
4. Breathe through your nose. This is essential. If you cannot breathe through your nose comfortably, address that first — a deviated septum, allergies, or chronic congestion may need medical attention before you can maintain proper tongue posture.

Common Mistakes

• Only using the tongue tip: The posterior tongue positioning is where most of the theoretical force application happens. If only the tip is up, you are not mewing effectively.
• Pushing too hard: Mewing is about a resting posture, not about actively shoving your tongue into the roof of your mouth. Excessive force can cause jaw pain, TMJ issues, and headaches.
• Clenching the jaw: Some people tense their masseter muscles when trying to hold the tongue position. This can lead to TMJ dysfunction and bruxism. Stay relaxed.
• Neglecting neck posture: Proper tongue posture is much easier to maintain with correct head and neck alignment. A forward head posture pulls the tongue away from the palate. Tuck your chin slightly and keep your head over your shoulders.
• Expecting overnight results: Even proponents of mewing acknowledge that any changes take months or years. Checking for results daily or weekly will only lead to frustration.

Realistic Expectations

Setting honest expectations is critical. The internet is saturated with dramatic mewing before and after transformations, but a closer look at these photos reveals several recurring issues:

• Lighting and angle changes: A slight change in lighting direction or camera angle can dramatically alter how the jawline and cheekbones appear in a photo. Overhead lighting hollows the cheeks; front-on lighting flattens the face.
• Body composition changes: Many mewing transformation posts span 1 to 3 years. During that time, weight loss, body fat redistribution, or simply aging (especially in teens going through puberty) can significantly change facial appearance.
• Puberty and natural growth: A large number of dramatic before and after photos come from teenagers whose faces are naturally changing through normal development. Attributing those changes to mewing is a classic post-hoc fallacy.
• Selection bias: People who perceive no results do not post about it. The before and after photos you see online are a self-selected subset that dramatically overrepresents positive outcomes.

What mewing can plausibly do for adults:

• Promote nasal breathing, which has well-documented health benefits for sleep quality, nitric oxide production, and cardiovascular health
• Improve head and neck posture through increased awareness of tongue and jaw position
• Produce subtle soft tissue changes over time — slight improvements in submental (under-chin) appearance as muscles adapt to new resting positions
• Reduce symptoms associated with mouth breathing like dry mouth and morning sore throat

What mewing almost certainly cannot do for adults:

• Significantly reshape the skeletal structure of the maxilla or mandible
• Produce dramatic changes visible in photos within weeks or months
• Replace orthodontic treatment or orthognathic surgery for actual structural issues
• Widen the palate once the midpalatal suture is fused

Evidence-Based Alternatives

If you want to improve your jawline and overall facial aesthetics, there are approaches with far stronger evidence behind them. Many of these work synergistically, and combining multiple strategies will yield the best results.

• Body composition optimization: This is the single most impactful thing most people can do for facial aesthetics. Reducing body fat percentage reveals underlying bone structure. A defined jawline is largely a function of low submental fat. No amount of tongue posture will overcome excess body fat in the face and neck area.
• Masseter training: Chewing hard foods or using dedicated jaw exercise tools can build the masseter muscles, creating a wider and more angular jaw appearance. Unlike skeletal changes, muscle hypertrophy is well-supported by exercise science and works at any age.
• Orthodontic treatment: If you have malocclusion, crowding, or bite issues, modern orthodontics (including clear aligners) can make real, measurable changes to tooth positioning and, in some cases, jaw alignment. Consult an orthodontist for an assessment.
• Orthognathic surgery: For severe skeletal discrepancies — a significantly recessed jaw, an underbite, or facial asymmetry caused by bone structure — jaw surgery is the evidence-based solution. It is a major procedure with real risks, but it produces genuine skeletal change that no amount of tongue posture can replicate.
• Posture correction: Forward head posture can make the jawline appear weaker and the neck area less defined. Correcting overall posture — strengthening the posterior chain, reducing screen-related forward head carriage — can meaningfully improve how your jaw and neck look from the side.

For a comprehensive, evidence-based approach to maximizing your jawline, check out our guide to jawline improvement, which covers all of these strategies in detail.

The Bottom Line

Does mewing work? The honest answer is: it depends on what you mean by "work" and how old you are. For children and adolescents, proper tongue posture and nasal breathing are genuinely important for healthy facial development, and correcting poor habits early may prevent problems. This is supported by legitimate pediatric orthodontic and myofunctional therapy literature.

For adults hoping to reshape their facial bones through tongue posture alone, the evidence is not there. The dramatic mewing results posted online are almost certainly explained by confounding factors like lighting, body composition changes, natural maturation, and selection bias. That does not mean the practice is harmful — proper tongue posture and nasal breathing are healthy habits worth adopting. Just do not expect them to replace the changes that body composition, exercise, orthodontics, or surgery can deliver.

The best approach is to adopt good oral posture as one small component of a broader strategy. Mew if you want to — it costs nothing and the breathing benefits alone are worthwhile — but pair it with the evidence-based approaches that actually move the needle.