It's easy to ignore the effects of poor oral hygiene because they're hidden in your mouth. But gum disease produces a bleeding, infected wound that's the equivalent in size to the palms of both your hands, says Susan Karabin, DDS, a New York periodontist and president of the American Academy of Periodontology.

"If you had an infection that size on your thigh, you'd be hospitalized," Karabin says. "Yet people walk around with this infection in their mouth and ignore it. It's easy to ignore because it doesn't hurt ... but it's a serious infection, and if it were in a more visible place, it would be taken more seriously."

You may think that the worst consequence of poor dental health would be lost teeth and painful times in the dentist's chair. But some studies have linked common oral problems to illnesses, including heart disease, stroke, diabetes, premature birth, osteoporosis, and even Alzheimer's disease. In most cases, the strength and exact nature of the link is unclear, but they suggest that dental health is important for preserving overall health.

"We need to educate the public that the mouth isn't disconnected to the rest of the body," says Sally Cram, DDS, a periodontist in Washington, D.C., and spokeswoman for the American Dental Association.

(Do you visit your dentist for regular checkups? Why or why not? Talk with others on WebMD's Dental Health: Support Group board.)

How Gum Disease Spreads

Periodontal disease is an infection caused by unhealthy bacteria that lodge between the teeth and gums. Simply brushing your teeth is enough to put some of those bacteria into your bloodstream, says Robert J. Genco, DDS, PhD, an oral biologist at the University of Buffalo. The bacteria then travel to major organs where they can spur new infections.

Inflammation also plays a role in spreading the effects of bad oral health. Red and swollen gums signal the body's inflammatory response to periodontal bacteria. "If you have inflammation in your mouth, certain chemicals are produced in response that can spread [through the bloodstream] and wreak havoc elsewhere in the body," Cram says.

Evidence is mounting of the importance of the "mouth-body connection," as it is known, as dental problems are being linked to a growing list of other ailments.

Oral Health and Diabetes

Karabin has diagnosed several cases of diabetes from her dentist's chair. "When I see a patient with multiple abscesses in their mouth ... I immediately think 'diabetes.' I will send that patient for a glucose tolerance test." Nearly one-third of people with diabetes are unaware that they have it, and dentists can play a big role in diagnosing these patients, Genco says.

Diabetes and gum disease can interact in a vicious circle. Infections of any kind, including gum disease, cause the body to produce proteins called cytokines, which increase insulin resistance and make blood sugar more difficult to control, Karabin says. Conversely, uncontrolled diabetes impairs the body's healing mechanism, which makes it harder to control gum disease, Cram says.