GUM DISEASE CAN LEAD to lost teeth, but the associated bacteria and inflammation in the mouth and gums are also linked to a number of cancers. A study published March 2022 in Cancer Causes & Control found people with a history of periodontal disease—a serious gum infection often caused by poor dental hygiene, also called gum disease—are 45% more likely to develop colorectal cancer than those with no history of periodontal disease.

How to Properly Floss

Flossing is only effective at protecting against gum disease if you do it correctly. The American Dental Association explains you should ease the floss between your teeth and hold the floss in a C-shape against one tooth. Next, slide it into the space between the tooth and the gums. Then gently scrape the side of your tooth, moving away from the gum line with up and down motions.

This isn’t a one-off finding. A March 2021 study of nearly 150,000 people published in the journal Gut found those with gum disease had a 43% increased risk of developing esophageal cancer and a 52% increased risk of developing stomach cancer during 22 to 28 years of follow-up.

Gum disease also was associated with a nearly 18% increased risk of developing breast cancer, according to a 2018 analysis of eight previous studies. And losing at least one tooth has been linked to an increased risk of several cancers, including cancers of the esophagus, stomach, pancreas, lungs, and head and neck.

“Oral health is a gateway to the body,” says Tom Salinas, a dental oncologist at the Mayo Clinic in Rochester, Minnesota. When people lack good oral hygiene, bacteria build up on and between teeth and at the gum line. It’s not difficult for those bacteria to get to other organs where they can cause greater systemic problems, including cancer, says Zafrulla Khan, a dental oncologist at the J.G. Brown Cancer Center in Louisville, Kentucky. The bacteria also can cause chronic inflammation, which plays a role in promoting tumor growth, adds Ronald Koslowski, a dental oncologist based in Los Angeles.

Visit Your Dentist

Cancer patients and survivors should consider seeing a dental oncologist.

Luckily, you don’t need to go to great lengths to maintain good dental hygiene. The American Dental Association (ADA) recommends brushing your teeth for two minutes twice per day to clear plaque and food particles from the surface of teeth. Floss your teeth daily to get rid of bacteria stuck between teeth and at the gum line. Alternatives such as water flossers can also work. According to the ADA, the best method for flossing is one you’ll do every day.