Hi! Many thanks for your question on eHealth forum!
Dizziness while eating could be due to acid reflux. The reverse flow of contents of the stomach cause a series of neurochemical transmissions, which cause dizziness. It is also related to changing pressure in the cochlear canals of the ear during this process. Normal GERD will not cause dizziness if under control. However a person with severe uncontrolled acidity or when such a person is hungry or his stomach is empty except for the acid, he may feel dizzy. Also presence of an ulcer in the stomach or weak esophageal sphincter can complicate matter. I would recommend you to see a gastroenterologist (a specialist who looks after the diseases of our digestive system).
The second possibility is that you have a TMJ disorder that precipitates dizziness once you start chewing. This is most likely cause. Many patients with TMJ have dizziness. There are two possible causes. One is that when TMJ is inflamed inner ear is affected causing dizziness. The second possible cause is inflammation of the sternocleidomastoid muscle (SCM) involved in TMJ and chewing.
You have to press on muscles of your face to look for sore points. To get some relief you can try massaging the sore muscles. Massaging the muscles does not help every one. Also if the procedure is nor correct, then it can further aggravate the problem. Then massage these points with short strokes. To massage the masseter muscles on each side of your jaw, place your thumb inside your mouth and squeeze the thick muscle in your cheek with your fingers. To massage the jaw muscles inside your mouth, use your index finger to probe and massage these spots. Moist heat or cold packs on the face, vitamin supplements, or biofeedback are useful for some people. Usually people find a method that brings relief by trial and error. Consult an ENT specialist. Hope this helps. Take care!