People with a history of gum disease have a 52% greater risk of stomach cancer and a 43% greater risk of throat cancer compared to people without gum disease, according to a new study led by researchers from Harvard T.H. Chan School of Public Health. Having lost two or more teeth also increased risk for these cancers (by 33% for stomach cancer and 42% for throat cancer).
The study was published online in the journal Gut on July 20, 2020.
“Participants with periodontal disease and a higher number of teeth lost had a higher risk of developing the two gastrointestinal cancers, even after adjusting for other major risk factors,” said senior researcher Mingyang Song, assistant professor of clinical epidemiology and nutrition, in a July 21, 2020 U.S. News & World Report article.
He said that the high systemic inflammation caused by periodontal disease could be contributing to cancer development. Growth of bacteria in the mouth and gums may also be a factor, he said.
In a separate study in the journal Cancer Prevention Research, Song and colleagues found that gum disease is also linked with an increased risk of colorectal cancer. Compared with people with no history of periodontal disease, those who had gum disease had a 17% increased relative risk of having a serrated polyp, and an 11% increased risk of a conventional adenoma, according to the study. The researchers also found that the loss of four or more teeth was linked with a 20% increased risk for having a serrated polyp.
Read a U.S. News & World Report article about the Gut study: Keep Flossing: Study Ties Gum Disease to Higher Cancer Risk
Read a New York Times article about the Cancer Prevention Research study: Gum Disease Tied to Colon Cancer Risk