Fizzy drinks firms told to come clean over use of 'addictive' caffeine

Soft drink manufacturers were accused yesterday of adding caffeine to carbonated beverages purely to make them addictive after a US study found that the drug has no effect on flavour for most people.

Soft drink manufacturers were accused yesterday of adding caffeine to carbonated beverages purely to make them addictive after a US study found that the drug has no effect on flavour for most people.

Scientists found that 92 per cent of people who regularly drink colas could not taste the caffeine in drinks such as Coca-Cola Classic or Pepsi.

Dr Roland Griffiths, a psychopharmacologist from John Hopkins Medical Institutions in Baltimore, who led the study, said it was time manufacturers were honest about caffeine.

"The marketing parallels between nicotine and caffeine are pretty stunning," he said. "Both are psychoactive drugs. Until recently, cigarette companies denied that nicotine is addictive and said it was added merely as a flavour enhancer for cigarettes. The same is being said for caffeine. This stands in sharp contrast to the claim some soft drink manufacturers make that they add caffeine purely for taste."

In the study of 25 adult cola drinkers, published in the Archives of Family Medicine, the scientists found that only 8 per cent, or two people, could detect caffeine in cola at a concentration of 0.1mg per millilitre. The rest of the group could not taste the difference between caffeinated and caffeine-free cola until caffeine levels were raised much higher than legally permitted.

"I'd like to see the soft drink industry come out of denial about the role of caffeine in their products," said Dr Griffiths. "They're adding a mildly addictive, mood-altering drug, one which surely accounts for the fact that people drink far more carbonated soft drinks with caffeine than without."

In Britain, 5560m litres of carbonated soft drinks are sold each year; colas represent 49 per cent of this with the vast majority of these, over 95 per cent, containing caffeine.

"Caffeine is not a drug. It is a flavouring," said Christine Milburn, of The British Soft Drinks Association. "Caffeine is found in lots of products and is in nature. Taste comes from a combination of ingredients not from one single ingredient and is very subjective," she said. "Carbonated soft drinks tend to be targeted at teenagers and the early twenties, with those aged 10 to 24 consuming 55 per cent of all carbonated drinks."

Dr Griffiths believes this is part of the problem. "Given that sodas are aggressively marketed to kids, manufacturers should openly say why the caffeine is there. We should tell what the caffeine dose is.

"We know adults and children can become physiologically and psychologically dependent on caffeinated soft drinks, experiencing a withdrawal syndrome if they stop," he said.