Tea 'may fight tooth decay'

Could your regular cuppa improve your smile?

Drinking tea may ward off tooth decay and bad breath, according to scientists.

A study suggests chemicals in tea can destroy bacteria and viruses that cause throat infections, dental caries and other dental conditions.

It raises the prospect of adding tea extracts to toothpaste and mouthwash to protect the teeth.

The study, presented at a meeting of the American Society for Microbiology, is the latest in a string of health claims about tea.

According to research by US microbiologist, Milton Schiffenbauer, of the independent Pace University, green tea is better at fighting viruses.

"Our research shows tea extracts can destroy the organism that causes disease," he told a conference in Washington DC.

"If we can stimulate the immune system and at the same time we are destroying the organisms, then it makes sense to drink more tea."

Bad breath

The latest research looked at green tea as well as black tea - the most popular beverage in the world.

It found that caffeinated green tea was the best at fighting viruses, followed by caffeinated black tea. Decaffeinated blends were less effective as anti-viral agents.

Another study looked at chemicals in tea known as polyphenols. Experiments in the laboratory showed they slowed the growth of bacteria associated with bad breath.

Christine Wu, of the University of Illinois at Chicago, said: "Besides inhibiting the growth of pathogens in the mouth, black tea and its polyphenols may benefit human oral health by suppressing the bad-smelling compounds that these pathogens produce."

But a UK researcher said it was too early to draw any firm conclusions before clinical trials on the dental benefits of tea were carried out.

"Tea may be an additional factor in our armamentarium against oral disease, " Dr Ian Douglas of the University of Sheffield Dental School told BBC News Online.

"But don't stop cleaning your teeth with conventional fluoridated toothpaste until there is more information."