Tea 'may fight tooth decay'

Drinking tea could mean fewer trips to the dentist, according to new research reported today.

Scientists in the US have found that the traditional cuppa may protect teeth against cavities.

There was already a suggestion from previous studies that oriental green teas might help prevent tooth decay.

But the new findings show that black tea, enjoyed by 80% of the world’s tea drinkers including millions of Britons, has a significant protective effect.

Dr Christina Wu and colleagues at the University of Illinois College of Dentistry found that compounds in black tea were able to kill cavity-causing bacteria or suppress their growth and acid production.

Black tea also affected a bacterial enzyme responsible for converting sugars into the ‘‘glue’’ tooth decay bugs use to adhere to teeth.

Exposed to black tea, certain plaque bacteria also lost their ability to clump together. The total mass of dental plaque was therefore reduced.

One study conducted by Dr Wu found that when volunteers rinsed with black tea for 30 seconds five times at three-minute intervals, plaque bacteria stopped growing and producing acid.

It is the acid made by bacteria which corrodes the teeth and creates cavities.

Dr Wu said: ‘‘It is our belief.. that the intake of black tea can be significant to improve the oral health of the general public.

‘‘If sequenced properly between meals and normal oral hygiene, a reduction in dental caries (tooth decay) may be possible.’’

The findings were presented at a meeting of the American Society for Microbiology in Orlando, Florida.