Your Jaw May Be to Blame for Your Headaches Updated for 2024 CMCL 4 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 Why You Should Stop Picking Your Nose Now! Why You Should Stop Picking Your Nose Now! Drink This Juice to Eliminate Pounds of Waste and Lose Weight