Chewing gum used to be frowned upon by dentists. Not only was it full of sugar, but it also remained in the mouth longer than candies that you could swallow, making it a greater cause of tooth decay. However, in the 1950s, manufacturers introduced sugarless gum, which used an artificial sweetener that did not corrode the teeth. This form of gum could be chewed regularly without causing cavities. However this did not diminish other concerns about its daily use.
The temporomandibular joint (TMJ) is the place where the jaw attaches to the skull. If the muscles that hold this joint in its correct alignment become fatigued, the joint can move out of place, causing a TMJ disorder. This often results in jaw pain, headache and reduced movement or locking of the joint. Moderate gum chewing does not usually cause TMJ disorders; however, habitual chewing can cause muscle fatigue that may put you at risk. Particularly hard or vigorous chewing is especially stressful on the joint and surrounding muscles.
Excessive gum chewing can wear the enamel off your teeth and change your bite. In particular, the upper molars tend to spread, while the lower ones diminish. The upper front teeth may also drift forward while the lower ones drift backward, creating an overbite. These changes may require orthodontic care to correct. Furthermore, as the enamel erodes, your teeth may become more sensitive to hot, cold and acidic foods.
When any muscle repeats the same motion for a long period of time, it can become fatigued. This applies to the facial muscles that are responsible for moving the jaw during chewing. As a further complication, most people primarily chew their gum on one side of their mouth, fatiguing the muscles unequally. This can cause headaches, especially when the chewing is rapid and vigorous, as it sometimes is when the chewer is under stress.
Sugarless gum sometimes contains aspartame, an artificial sugar whose effects remain controversial. One study, which appeared in Life Sciences Journal, concluded that aspartame may help create formaldehyde in the body, which is a known carcinogen. Some claim that they have experienced side effects, such as headaches, dizziness and mood swings, as a result of eating foods with this ingredient. However, neither the FDA or the American Cancer Society have issued warnings about consuming aspartame, except in the case of people with phenylketonuria, or PKU, whose bodies lack the enzyme necessary to break it down.