However, the researchers are hesitant to give omega-3's full credit just yet, as other factors might be involved, too.
Advanced gum disease, known as periodontitis, is a chronic inflammation caused by the accumulation of bacteria at the gum line. The condition can lead to bone and tooth loss.
"The bacteria involved seem to need inflammation to grow," senior researcher Dr. Kenneth J. Mukamal of Harvard Medical School, Boston, told Reuters Health in an e-mail. "Indeed, anti-inflammatory treatment with omega-3's seems to help experimental periodontitis in rabbits. Our hope was to extend that to humans."
Mukamal and his colleagues studied more than 9,000 adults, all participants in the National Health and Nutrition Examination Survey between 1999 and 2004.
About eight percent of the participants had gum disease, report the researchers in the Journal of the American Dietetic Association.
Based on the participants' recalls of their diets over the previous 24 hours, the team found that those who consumed intermediate or high amounts of one of the main fish-derived omega-3 fatty acids, DHA, were less likely to have the disease.
After taking into account factors such as age, sex, and calorie intake, the top third of patients in terms of DHA intake had a 22% reduction in their odds of developing gum disease compared with those in the lowest third.
The researchers also found a lower rate of gum disease among participants with relatively low blood levels of C-reactive protein, a sign of inflammation.
Still, Mukamal cautioned that the findings don't yet confirm that omega-3's have a true protective effect on the gums. For example, tooth loss could have affected diets of the participants, rather than the other way around.
They also didn't obtain enough information in the study to pinpoint just how much omega-3 is best for the prevention of periodontitis, should it eventually prove to be protective.
Mukamal did highlight the American Heart Association's recommendation of two meals per week of fatty fish -- such as salmon, mackerel, herring, or albacore tuna -- and noted that this "seems like a very reasonable amount."
Some earlier research has pointed to health benefits associated with fish oil, although the exact effects are still not clear.
"Omega-3's have a wide number of potentially beneficial effects on many organs," said Mukamal. "The gums may be a new one that hasn't been appreciated before."
For gum disease prevention, he also advises going to a dentist for regular cleaning, and if recommended, seeing a gum specialist for antibiotics or more aggressive cleaning.
By Lynne Peeples
Journal of the American Dietetic Association, November, 2010.
Last Updated: 2010-11-10 16:35:04 -0400 (Reuters Health)
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