Schoolboy scientist shatters Coke myth

By ANGELA GREGORY

An 11-year-old Tauranga school boy has drilled holes in the urban myth that Coca-Cola rots teeth the quickest.

Max Lynam's science project has demonstrated that while Coke has an effect, other drinks, including some fruit juices, are more than twice as corrosive on tooth enamel.

The Otumoetai Intermediate student soaked wisdom teeth in energy drinks, soft drinks and fruit juices for a fortnight to see which were the most harmful to enamel.

By comparing the weights of the teeth before and after, Max found the energy drink V came out on top , having eroded 31.9 per cent of the tooth.

Just Juice came second at 28.8 per cent, followed by Raro at 14.6 per cent.

The tooth soaked in Coca-Cola showed just 12.5 per cent enamel loss, a little more than pure orange juice, which dissolved 10 per cent of the tooth.

Diet Coke was the safest, dissolving 4.5 per cent.

Max said he was surprised at the results because he had always thought Coca-Cola was the worst tooth rotter.

"My dad's a dentist and he always goes on about keeping off Coke."

Max said his experiment had put him off fizzy and fruit drinks, and he would now try to stick to milk or water.

Head of the oral health department at Otago University, Dr Bernadette Drummond, said Coca-Cola was not as harmful as some other drinks because it had lots of phosphates which slowed down tooth erosion.

While sugar and acid in the soft drink would still attack enamel, Dr Drummond said the phosphates slightly slowed down the demineralisation of teeth, which would explain the experiment findings. But Dr Drummond said even the worst fizzy drinks could be drunk safely.

The danger to teeth came from people sipping the drinks over a prolonged period, she said.

Those at risk included toddlers with feeder bottles filled with fruit juice, teenagers who put fizzy drinks in sipper bottles, and athletes who sipped on sports drinks.

The prolonged intake of such drinks interfered with the effectiveness of saliva, full of calcium and phosphate, from remineralising the teeth.

Dr Drummond recommended fruit or fizzy drinks only be served with meals, be drunk straight away, and ideally swallowed through a straw.

"Some kids take a mouthful and let it fizz around their teeth ... that's the worst thing to do."

Frucor Beverages general manager technical Dr Eric Wilson said the drinks V and Just Juice distributed by the company were not dangerous to oral health.

Food technologist Dr Wilson said any enamel erosion would be minimal because of the short time the drinks stayed in the mouth and the neutralising effect of saliva.

Coca-Cola referred the Herald to the Australasian Soft Drink Association whose spokesman, Tony Gentile, said isolating a particular product as a cause of dental erosion was simplistic.

Mr Gentile said tooth erosion was relatively rare and easily misdiagnosed, with susceptibility widely ranging between people.