Your Jaw May Be to Blame for Your Headaches Updated for 2026 CMCL 6 years ago Biting your nails, chewing on pen caps, or chewing a lot of gum may be the cause of your headaches. Did you know? If you have any of those habits, you might have temporomandibular dysfunction (TMD). Related Video Posts Your Legs Weaken First! Eat These 5 Cheap Vegetables to Rebuild Strength FAST After 60 5 Vegetables That FORCE Your Leg Muscles to Grow Again After 60 Over 60? THIS Green Leaf Protects Your Retina, Macula and Night Vision