Eau no! Now scientists say f izzy WATER makes us fat

AS THE list of foods deemed ‘bad for us’ grows ever longer, it sometimes seems that all we can safely eat is salad washed down with a glass of sparkling water.

But new research indicates that even this healthy option might contain hidden dangers because, rather than making you feel full, the carbon dioxide in fizzy water may actually make you fat by encouraging you to eat more.

Scientists have discovered that when we ingest the gas in a drink, it triggers a surge in a key hunger hormone.

Academics who studied rats found those that were given ‘flat’ sugary drinks alongside their normal diet put on no more weight than those given still water. But those given fizzy drinks – including zero-calorie versions containing artificial sweeteners – piled on weight.

Anti-obesity campaigners have called for action if studies show similar effects in humans.

However, the soft drinks industry has said there is no evidence that CO2 causes obesity in people.

In the study, researchers from Birzeit University in the Palestinian West Bank took 16 rat siblings of the same weight and split them into four groups. The first group was given water, the second a sugary soft drink with no gas, the third a ‘standard’ fizzy drink containing sugar and the fourth a ‘diet’ fizzy drink containing artificial sweetener. All were given access to unlimited food. After three months, those given the two fizzy drinks weighed significantly more than those given flat drinks.

The researchers calculated that the rats given fizzy drinks ate 20% more on average than those given flat beverages.

After a year, the rats given carbonated drinks showed signs of fat accumulating around their vital organs – a sign of chronic obesity. Tests showed levels of the hunger hormone ghrelin were ‘significantly higher’ in rats after ingesting a fizzy drink. The researchers then carried out tests on 20 healthy human volunteers. They found those given sparkling water to drink at breakfast had ghrelin levels six times higher than those given still water.

However, the British Soft Drinks Association last night cast doubt on the relevance of the research. Its director-general, Gavin Partington, said: ‘There is no body of scientific evidence that carbon dioxide contained in soft drinks – or even beer – causes increased hunger or obesity. It is bad science just to assume that an outcome from a study on rats will be the same for humans.’