Green tea contains antimicrobial molecules called catechins that may promote dental health, researchers claim.
"Green tea may have bacteriocidal effects, which would affect teeth, but only if you drink it without sugar," said Alfredo Morabia, of Columbia University in New York and editor of Preventive Medicine, who wrote an editorial accompanying the new research.
"They also reported that drinking sweet coffee was actually deleterious," he added. "Coffee alone had no problem, but sweet coffee would actually make you lose your teeth."
To reach the conclusion, Yasushi Koyama of the Tohoku University Graduate School of Medicine and colleagues looked at more than 25,000 Japanese men and women between age 40 and 64.
They found that men who drank at least one cup of tea a day were 19 percent less likely to have fewer than 20 teeth (a full set including wisdom teeth is 32) than those who did not drink green tea. Tea-drinking women had 13 percent lower odds.