The controversial fizzy alcoholic drinks are so acidic that they could rot people's teeth, say Dr Elizabeth O'Sullivan and Professor Martin Curzon in the British Dental Journal.

The dangers came to light following the case of a 17-year-old from Yorkshire whose teeth had rotted so badly that his fillings were sticking up above his teeth enamel.

The youth complained that his teeth hurt, particularly the morning after a night out with his friends. He admitted that he went out most nights with his friends, drank beer and several bottles of alcopop and often vomited because he was so drunk.

His dentist capped his teeth and advised him of the damage caused by the acid in the alcopops combined with the stomach acid produced when he was sick.

He cut down on drinking and stopped vomiting and, within six months, his teeth had stopped rotting.

Too many alcopops

Dr O'Sullivan and Professor Curzon say they fear many young people could be at risk of tooth decay because they drink too many alcopops.

Over �265m worth of the fizzy drinks were sold in 1996 and, despite denials that they are aimed at young people, reports show they are very popular among teenagers.

"People need to be alerted to the substantial damage that these acidic drinks can do to teeth," say the researchers.

"Anyone who drinks alcopops regularly should consider reducing the amounts they drink and the frequency with which they drink them. They should also see a dentist regularly."

Fizzy drinks, fruit juices and citrus fruits can all wear teeth down. And recent research showed that drinking too much wine could be bad for your teeth because it is acidic.