TUESDAY, Oct. 26 (HealthDay News) -- Eating even moderate amounts of omega-3 fatty acids, typically found in foods such as salmon and other fatty fish, may help ward off gum disease, new research suggests.

Researchers divided nearly 9,200 adults aged 20 and up participating in the National Health and Nutrition Examination Survey between 1999 and 2004 into three groups based on their consumption of omega-3 fatty acids. Consumption was assessed by asking participants to recall exactly what they'd eaten during the prior 24 hours.

Dental exams showed participants in the middle and upper third for omega-3 fatty acid consumption were between 23 percent and 30 percent less likely to have gum disease than those who consumed the least amount of omega-3 fatty acids.

Specifically, the researchers found that the omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were associated with less gum disease. The association with linolenic acid (LNA) was not statistically significant.

"Eating a very feasible amount of fatty fish seems to have a lot of benefit," said senior study author Dr. Kenneth Mukamal, an associate professor of medicine at Harvard Medical School. "But we found no benefits to eating tons of this stuff."

Since the study was a snapshot of a single day's diet, Mukamal said researchers could not determine exactly how much fish oil people should consume regularly. But following guidelines from major organizations such as the American Heart Association, which recommends eating fatty fish at least twice a week, is probably a good idea, not just for gum disease but for overall health, they noted.

"There are a lot of benefits of omega-3 fatty acids. We have good evidence they prevent sudden death caused by heart rhythm disturbances. We have some evidence omega-3 fatty acids can reduce the risk of heart attacks and stroke," Mukamal said. "This is a great example of another potential benefit."

In the study, researchers took into account other factors that could affect the likelihood of having gum disease, such as age, income, education and other health and socioeconomic factors.

The study is published in the November issue of the Journal of the American Dietetic Association.

Periodontitis is a chronic inflammation of the gums caused by bacteria that accumulate around the gum line, according to background information in the study. Over time, the gum tissue can recede and separate from teeth, leading to "periodontal pockets," or spaces between the gums and the teeth, and loss of the bone that provides the supporting structure for the teeth.

About 54 percent of men and 46 percent of women over age 30 in the United States experience gingival bleeding, the earliest sign of periodontal disease, according to background information in an accompanying editorial.

In the general population, about 11 percent of adults aged 50 to 64 have moderate or severe periodontitis, rising to 20 percent of those over age 75. In the study, about 8.2 percent of participants had periodontitis.

The usual treatment of periodontitis is good dental hygiene, including manually removing bacteria during dental appointments and applying local antibiotics to kill the bacteria, though there is disagreement among dentists about how well local antibiotics work.

In an accompanying commentary, Elizabeth Krall Kaye, a professor in the department of health policy and health services research at Boston University Henry M. Goldman School of Dental Medicine, said the study supports incorporating fatty fish into one's diet, but not necessarily fish oil supplements.

"The study is interesting in that they studied a large population, and they saw some benefit just from consuming moderate amounts of omega-3 fatty acids," Kaye said.

Other sources of omega-3 fatty acids include sardines, mackerel and swordfish, along with some nuts and seeds such as walnuts and flax seed.

More information

The American Heart Association has more on omega-3 fatty acids.