It might not be the garlic or onions, coffee or alcohol. Rather, a new study links it to the types of bacteria that dominate the back portion of the top of your tongue. Some bacteria protect against halitosis, the formal name for really bad breath, while others cause the pungent odor, says a team of researchers from The Forsyth Institute in Boston. "I think there's a definite smoking gun here -- that it's a strong association," says lead researcher Bruce Paster. "There are the good bacteria and the bad ones." The study, reported in the February issue of the Journal of Clinical Microbiology, relied on gene sequencing to compare bacteria found on the tongues of those with halitosis and those with fresh breath. Researchers reported species of the same three bacteria were prevalent among five people with fresh breath. The most common of these germs found on these subjects' tongues, Streptococcus salivarius, appeared in only one of six people with halitosis -- and at extremely low levels. Six species of bacteria were linked to halitosis, and several of those germs were not found in those with fresh breath. About 65 million Americans suffer from halitosis at some point in their lives, the National Institute of Dental Research has estimated. (Agencies) | 研究發現,口腔異味并不一定是因為大蒜、洋蔥、咖啡或酒精引起的,罪魁禍首有可能是位于舌尖背部的幾種特殊類型的細菌。 來自波士頓福塞斯研究所的一個研究小組發現,口腔內有一些細菌可以防止口臭,也就是口腔異味的產生,而另一些的作用則剛好相反。 研究小組的領導者布魯斯·帕斯特說:"我們有確鑿的證據表明--口氣和這些細菌之間是有聯系的。有的細菌能令口氣清新,同時也有能引起口臭的細菌。" 這一研究結果發表在二月的《臨床微生物學》雜志上。文中,研究人員是通過基因序列比較口氣有異味和無異味人群口腔內的細菌種類來論證這一結論的。 研究人員發現,在五名沒有口臭的試驗對象口腔中,都有同樣的三種細菌,其中含量最高的是唾液鏈球菌。而在六名有口臭的人士中,只有一個人的口腔中有這種細菌,而且含量很低。 研究人員共發現了六種能引起口臭的細菌,其中幾種是口氣清新的人口中所沒有的。 據美國國家牙科研究所估算,約6千5百萬美國人有不同程度的口臭。 (中國日報網站譯) |