Why do I clench my jaw during the day?
Last updated September 3, 2026.
It is usually stress or deep focus, not a jaw defect. The NHS lists stress and anxiety as the most common cause of teeth grinding and clenching, with sleep problems, smoking, and heavy caffeine or alcohol intake as contributors. Awake clenching is the same reflex during the day: concentration and tension tighten the jaw muscles without you noticing. Over time it can wear teeth, trigger temple headaches and earache, and feed temporomandibular disorder. The first-line fix is catching yourself: teeth apart, tongue as a spacer, lips closed, jaw relaxed, plus work on the stress driving it.
What to do
- Set clench-check reminders during focused work; awareness breaks the habit loop.
- Use the resting position: lips together, teeth apart, tongue resting between them.
- Cut the amplifiers: excess caffeine, alcohol, and smoking are all NHS-listed contributors.
- See a dentist if teeth are wearing or hurting; a guard and a TMD check may be next.
Related questions
- Why does my jaw click?
- Why do I get headaches behind my eye?
- Why do I get a dry mouth at night?
- Why are my teeth sensitive?