New studies show a correlation between gum disease and rheumatoid arthritis (RA).

In fact — it’s more than just a subtle link. RA and gum disease might actually share a common origin.

The specifics of the relationship between RA and gum disease are not perfectly clear, but what is apparent is that having either condition puts you at risk for the other.

And now, new studies show that isn’t where the commonalities end.

Researchers have recognized a link between gum disease and RA for many years — that part is nothing new.

Over the decades, several studies have shown that people with RA are more likely to develop gum disease than their RA-free counterparts — even up to .

A German study showed that when people with RA developed gum disease, it was more aggressive and severe than in people with gum disease who didn’t have RA.

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Linking inflammatory conditions

It is well-documented that RA and gum disease are both inflammatory diseases that attack healthy tissue. But now science is showing that they may even share certain biomarkers in the blood, and a possible genetic link.

A study out of Israel noted that a genetic marker called HLA-DR4, which is often seen in people with RA, was also present in 80 percent of people with gum disease.

A possible genetic link isn’t the only theory. According to the National Rheumatoid Arthritis Society, people in the United Kingdom who have gum disease were up to four times more likely to have RA than those without.

One theory is that bacteria from gum disease can increase inflammation throughout the body, which may increase the risk for an autoimmune condition like RA.

The Arthritis Foundation and European League Against Rheumatism have often written about the role that oral health plays in RA, noting that the way you take care of your teeth could play a role in joint health.  These organizations also presented many studies on the topic at the annual EULAR conference.