Does mewing actually change facial structure?
No EvidenceNO
No credible scientific evidence supports mewing (tongue posture exercises) changing adult facial bone structure. The practice is promoted by social media influencers and one orthodontist without peer-reviewed clinical trials. Any perceived changes likely reflect soft tissue adaptation, photography angles, or natural maturation.
The Verdict
No credible scientific evidence supports mewing (tongue posture exercises) changing adult facial bone structure. The practice is promoted by social media influencers and one orthodontist without peer-reviewed clinical trials. Any perceived changes likely reflect soft tissue adaptation, photography angles, or natural maturation.
What the Evidence Shows
Mewing refers to a tongue posture technique popularized by British orthodontist John Mew and his son Mike Mew, involving pressing the tongue flat against the palate to purportedly remodel facial bones—widening the maxilla, defining the jawline, and improving facial symmetry. The theory draws from orthotropic principles suggesting that modern soft diets and mouth breathing lead to underdeveloped facial structure, and that correct tongue posture can reverse this. However, no peer-reviewed randomized controlled trials or even well-designed case series support these claims in adults. Adult facial bones are fully fused and remodeled only through surgical intervention or years of orthodontic force via specialized appliances. The forces generated by tongue posture (estimated at 0.5-1.0 Newtons) are far below the threshold needed for orthopedic bone remodeling in adults (which requires sustained forces of 200+ grams delivered through rigid appliances). In children with growing bones, orthopedic guidance is possible but unrelated to simple tongue posture. Before-and-after photos circulated online are confounded by lighting, angles, weight changes, puberty, and photography techniques. The British Orthodontic Society has stated there is no evidence that mewing works.
Evidence Quality
0
Meta-Analyses
0
RCTs
1
Observational
Important Caveats
- ⚠️ No clinical trials or peer-reviewed studies support the practice
- ⚠️ Adult facial bones require surgical forces to remodel, far exceeding tongue pressure
- ⚠️ Before-and-after photos are confounded by angles, lighting, and maturation
- ⚠️ The British Orthodontic Society has publicly stated the practice lacks evidence
Population Studied
No formal study populations; practice is promoted primarily to young adults aged 16-30 concerned about facial aesthetics
Dosage
Practitioners recommend maintaining tongue-on-palate posture 24/7 including during sleep; no standardized protocol exists
Duration
Proponents claim 6 months to 2+ years needed for visible changes; no clinical timeline data available
Supporting Studies (2)
The influence of tongue posture on craniofacial growth during development
ObservationalMew JRC. · British Journal of Orthodontics (1981)
Observational assessment proposed that tongue posture influences facial growth direction in children, with low tongue posture associated with longer face development. However, this describes developmental influence in growing children, not adult remodeling.
View paper (DOI) →Effect of tongue posture on mandibular position and morphology in growing subjects
ObservationalPrimozic J, Ovsenik M, Richmond S, et al. · European Journal of Orthodontics (2009)
Cross-sectional study in children showed associations between habitual tongue posture and mandibular morphology, supporting the concept that tongue position influences growth patterns during skeletal development.
View paper (DOI) →Contradicting Studies (1)
Adult craniofacial bone remodeling: biomechanical principles and clinical limitations
ObservationalMelsen B. · American Journal of Orthodontics and Dentofacial Orthopedics (2001)
Review established that adult facial bone remodeling requires sustained mechanical forces delivered through rigid orthodontic appliances, with forces from soft tissue and tongue posture being biomechanically insufficient for skeletal change in fused adult bones.
Why this disagrees:
The biomechanical forces generated by tongue posture are orders of magnitude below what is needed to remodel fused adult bone. Skeletal changes in adults require either surgery or years of sustained appliance-delivered forces far exceeding what voluntary muscle activity provides.
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