Those who don’t brush their teeth regularly may be putting themselves at greater risk of contracting pneumonia.

Samit Joshi, a postdoctoral fellow in infectious diseases at the Yale University School of Medicine, presented a study at the Infectious Diseases Society of America’s annual meeting in Boston, claiming that changes in the types of oral bacteria can have a significant impact on the risk of developing pneumonia. Joshi cited poor oral hygiene as one of the most common risk factors for pneumonia, with the risk doubling if a person has severe gum problems.

The study analyzed the oral health of 37 subjects, from a variety of age and health backgrounds, over the period of one month. Though only a small percentage of the patients developed pneumonia, those who did acquire the disease also saw significant increases in the number of oral bacteria associated with pneumonia.

“Our findings might improve the way we prevent pneumonia in the future by maintaining [the types of] the bacteria which live within our mouths,” Joshi said in an interview with the Global Medical News Network (GMNN).

While the study was not designed to demonstrate the direct relationship between pneumonia and these bacteria, Joshi told the GMNN that he hopes his experiment will be replicated by larger independent studies to determine a causal link.

Upon hearing the findings of the study, the British Dental Health Foundation, an oral health charity, issued a press release stating that poor oral hygiene may lead to the development of pneumonia.

“During the winter months we’re all susceptible to colds, coughs and chesty viruses due to the drop in temperature,” Nigel Carter, the foundation’s chief executive, said in an interview in The Telegraph. “What people must remember, particularly those highlighted as vulnerable, is that prevention can be very basic.”

Carter added that links between gum disease and overall health have been well-documented, and that keeping up good oral health can help stave off illness.

Sheldon Campbell, a professor of microbiology at the Yale School of Medicine who was not affiliated with the study, said that while he was not surprised by Joshi’s findings, they are significant because they place an even greater emphasis on oral hygiene. While there are many variables that might affect the development of a disease, poor oral hygiene will likely negatively affect patients, Campbell said.

“Most of the bacterial organisms that cause infections are neighbors of the oral floor,” he said. “There are too many variables to accurately say, but it’s likely that oral microbodies probably impact the development of certain diseases.”

Approximately 3 million Americans are infected with pneumonia annually.