Please floss and brush, by all means. It's still good for your teeth and gums.
But don't imagine that you're going to ward off heart disease in the process.
That's the message of a new "scientific statement" from an expert committee of the American Heart Association, which analyzed more than 500 papers and articles on the topic.
The idea that periodontal disease might impair the cardiovascular system dates back more than a century, according to the statement, published in the journal Circulation, and the hypothesis had a resurgence beginning about 20 years ago. Indeed, people with bad gums are more likely to have strokes, heart attacks, and hardening of the arteries.
But for now, there is no evidence that one causes the other, the committee wrote. The apparent reason for the link is that both have other risk factors in common, such as cigarette smoking, age, and type 2 diabetes.
Dentists appear to be comfortable with the new conclusions. The American Dental Association's Council on Scientific Affairs endorsed the heart association's report.
It is still possible that new evidence will show gum disease contributes to cardiovascular disease, but further study would be needed, said cardiologist Ann F. Bolger, cochair of the committee that wrote the statement.
"Always have an open mind to learn something new if there's better data tomorrow," said Bolger, a professor at the University of California, San Francisco. "But right now, and having looked at it very carefully and fairly exhaustively, we can't support any causal relationship."
Gum disease was thought to contribute to heart disease in several possible ways. Gum inflammation could contribute to overall bodily inflammation, or bacteria from the mouth could spread and somehow damage the circulatory system.
A better explanation may be simply that people who take poor care of their oral health may also take poor care of their cardiovascular health, said committee cochair Peter Lockhart, a professor of oral medicine at the Carolinas Medical Center in Charlotte, N.C.