In the old days, some advocated washing your mouth out with soap if you said something they thought was "dirty." While that's been abandoned as a popular tool of discipline, no one should ever give up on the idea of keeping the mouth clean and healthy.

When food gets lodged between teeth, plaque builds up around the gums and you can develop gingivitis (with red, swollen, bleeding gums). That is reversible. But if left untreated, it leads to periodontal disease (with chronic inflammation that damages teeth, bone, and tissue).

At that point, you've opened yourself up to a wide range of associated diseases, including diabetes, heart and respiratory conditions, some cancers, cognitive dysfunction, and even Alzheimer's.

A new study finds that if you have gums that often or always bleed when you brush your teeth, you're also at increased risk for asthma, chronic obstructive pulmonary disease (COPD), and chronic bronchitis.

For bacteria, the mouth is the gateway to your lungs — and gum disease throws your healthy oral biome out of balance, welcoming in potential troublemakers.

That's why it is so important to brush twice a day, floss daily (try a water-pick-like device), and see your dental professional for a checkup and cleaning at least twice annually.