Scientists link oral bacteria to obesity

WASHINGTON, July 8 (Xinhua) -- In a study that may help investigators learn new ways to fight the obesity epidemic, U.S. researchers found that certain oral bacteria may be helping to make us fatter.

J. Max Goodson and colleagues from Boston-based Forsyth Institute reported Wednesday in the Journal of Dental Research that the salivary bacterial composition of overweight women differs from non-overweight women.

The researchers collected saliva samples from 313 overweight women and 232 healthy individuals, and used DNA analysis to measure the two groups' salivary bacterial populations.

They found significant differences in seven of the 40 species studied in the salivary bacteria of subjects in the overweight group.

In addition, more than 98 percent of the overweight women could be identified by the presence of a single bacterial species called Selenomanas noxia.

"These data suggest that the composition of salivary bacteria changes in overweight women," the researchers said in a statement. "It seems likely that these bacterial species could serve as indicators of a developing overweight condition and possibly be related to the underlying causation."

The reasons for the link between obesity and oral bacteria are likely complex, they said, adding that the link may be circumstantial as being related to diet or opportunistic due to metabolic changes.