Chewing on One Side: Can It Make Your Face Asymmetrical?
Chewing on one side works the jaw muscle on that side harder, and over time it can make that corner of your jaw look wider. Whether it changes your whole face is less clear than the internet suggests. Here's what the research shows and how to even it out.
TL;DR
It mainly affects the jaw muscle, not the whole face. The masseter on your chewing side can grow with the extra work, widening that jaw corner. But a study of 748 adults found your preferred chewing side had no significant effect on overall facial asymmetry (Acta Odontologica Scandinavica, 2024). The most useful question is why you favour one side, because that reason, often a tooth, is usually the thing to fix.
Does chewing on one side make your face asymmetrical?
Chewing on one side can make the jaw muscle on that side bigger, but the evidence that it reshapes the whole face is mixed. The masseter, the thick muscle over the back corner of your jaw, responds to work like any other muscle, and clinical reviews list one-sided chewing alongside clenching and grinding as habits linked to it enlarging, sometimes on one side only (Sonar & Panchbhai, F1000Research).
When researchers measure the face as a whole, the picture gets less dramatic. The Northern Finland Birth Cohort study 3D-scanned 748 adults and tested which side each one chewed on. Preferred chewing side did not have a statistically significant effect on facial asymmetry (Heikkinen et al., 2024). A smaller Czech study of 163 adults did find a link, but only in men: right-side chewers tended to have a slightly more prominent right half of the face, and left-side chewers the left (Harnádková et al., Scientific Reports, 2024).
The takeaway: if your extra width sits right at the back corner of the jaw, your chewing side is a strong suspect. If your whole face looks lopsided, chewing is probably a small part of a bigger mix that includes bone, bite, sleep and posture. The full list is in why one side of your face is bigger.
Why you chew on one side
One-sided chewing is usually a response to something, not the root problem.
A tooth problem on the other side
Sensitivity, a cavity, a cracked tooth or a filling that sits high makes you protect that side without thinking about it.
Missing teeth
In the Finnish cohort study, a single missing tooth on one side made people about 2.4 times more likely to chew on the other side.
Jaw pain
Pain in the jaw joint or muscles on one side shifts chewing to the comfortable side, and the habit can outlast the pain.
Your bite
A bite that meets better on one side gives that side more chewing power, so food naturally goes there.
Plain habit
Some people simply always start on the same side, the same way they always lead with the same hand.
Signs you favour one side when you chew
Most people don't know their chewing side until they look for it. These are the giveaways.
- Food always ends up on the same side of your mouth before you start chewing.
- Clench gently and press both jaw corners: one bulge feels firmer or thicker.
- Gum always migrates to the same side.
- Your dentist mentions more wear on one side's teeth.
- The jaw corner on your chewing side looks wider in level photos.
How to stop chewing on one side
You stop chewing on one side by removing the reason first, then retraining the habit:
- Get the quiet side checked. If that side is sensitive, sore or missing teeth, no amount of willpower will make it comfortable. A dentist can tell you whether there's something to fix.
- Start every meal on your weaker side. The first few bites are where the habit lives. Moving food across deliberately for a few weeks is usually enough to make it automatic.
- Split your gum. If you chew gum, alternate sides, and don't overdo it. Heavy gum chewing mostly builds jaw muscle, as covered in does chewing gum help your jawline.
- Watch for clenching. Daytime clenching and night-time grinding load the same muscle. Teeth apart, lips together is the relaxed resting position.
- Be patient. Muscle changes take months, not days. Track it with photos taken the same way each time.
Can chewing on the other side fix facial asymmetry?
Chewing on your quieter side can help when the difference is mainly a bigger jaw muscle, and it does nothing for bone. Sharing the work lets an overworked masseter settle while the other side gets more use, which can narrow a jaw-corner difference over months.
Two warnings. First, aim to balance your chewing, not to swap your favourite side, or you'll eventually build the same problem on the other side. Second, don't try to speed it up by grinding through hard gum or jaw trainers on one side; that strains the joint. If your jaw clicks, locks, aches or your ears hurt when you chew, that points at a jaw joint problem (TMD), which needs a dentist or doctor rather than more chewing.
For the other habits that feed asymmetry, sleep position included, see does sleeping on one side cause facial asymmetry and the full plan in how to fix facial asymmetry.
Track your jaw symmetry over time
Jaw changes are slow enough that you won't see them in the mirror day to day. Take the free Face Symmetry Test now for a baseline: it compares your eyes, brows, cheeks, jaw and smile side to side and shows the regions that differ most. Repeat it every month in the same light and at the same distance.
The Symmetry IQ app does the tracking for you, scoring 8 facial-symmetry measurements on each scan and building a daily routine around the habits, like chewing and sleep, that you can actually change.
See how even your jaw really is
One level selfie gives you a 0-100 symmetry score and shows which regions, jaw included, differ most. Track it in the Symmetry IQ app while you even out your chewing.
Chewing on one side: frequently asked questions
Is chewing on one side bad?
Having a preferred side is very common and usually harmless. It becomes a problem when it's caused by something that needs fixing, like a painful tooth or missing teeth, or when it comes with jaw pain, clicking or headaches. Those are worth a dental check.
Can chewing on one side make your face asymmetrical?
It can make the jaw muscle on your chewing side bigger, which widens that corner of the jaw. Large studies are mixed on whether it changes the face as a whole: a Finnish study of 748 adults found no significant effect on overall facial asymmetry.
Can chewing on the other side fix facial asymmetry?
Evening out your chewing can let an overworked muscle settle and the quieter side catch up a little, so it can help when the difference is mostly at the jaw corner. It won't change bone, and deliberately overworking one side with hard gum can strain the jaw.
Why do I only chew on one side?
Usually because the other side is less comfortable or less effective: a sensitive or missing tooth, a filling or crown that sits differently, or jaw pain on that side. Sometimes it's just habit. Missing teeth on one side made people more than twice as likely to chew on the other in one large study.
How long does it take to even out after switching sides?
Muscles change slowly. Expect a few months of consistently splitting your chewing before any visible difference at the jaw corner, and check with photos taken the same way rather than the mirror.
Does chewing on one side cause TMJ problems?
It's one of several habits linked to jaw joint and muscle problems, alongside clenching and grinding. If your jaw clicks, locks, aches or your ears hurt when you chew, see a dentist or doctor rather than trying to train it away.
Which side should I chew on?
Both. The goal is to share the work, not to switch your favourite side. Start meals on your less-used side and move food across deliberately until it becomes automatic.
Sources
- Heikkinen EV, et al. Chewing Side Preference, Facial Asymmetry and Related Factors in the Northern Finland Birth Cohort 1986. Acta Odontologica Scandinavica, 2024.
- Harnádková K, et al. The relationship between facial directional asymmetry, handedness, chewing side preference, and eyedness. Scientific Reports, 2024.
- Sonar PR, Panchbhai AS. Masseter hypertrophy: a case and review. F1000Research, 2024.
- NHS. Temporomandibular disorder (TMD).
- NHS. Teeth grinding (bruxism).