You are using an older browser version. Please use a supported version for the best MSN experience.

Health Top Stories

Carbonated water in fizzy drinks could be causing sneaky weight gain, study suggests

9Coach logo 9Coach 20/05/2017 Sam Downing
Where possible, just drink plain old calorie-free water. © Shutterstock Where possible, just drink plain old calorie-free water.

Sipping on a fizzy drink could compel you to eat more than if you’d just downed a glass of water, according to research that probed how carbonated beverages affect appetite.

For the study, published in the journal Obesity Research and Clinical Practice, a research team from Birzeit University in Palestine gave lab rats one of four different types of drinks: a carbonated drink, a diet carbonated drink, a degassed carbonated drink (that had gone flat), and regular water.

Over the course of the year-long study, the rats were allowed to eat as much as they liked. At the end of the year, the rats who drank water and flat drinks had put on significantly less weight than the others.

Researchers determined that was because the rats who drank the carbonated drinks had secreted a lot more ghrelin — the “hunger hormone” that sparks your appetite.

In a separate part of the study, 20 healthy university students had their blood tested after downing either water or the different varieties of carbonated drink. Their ghrelin levels were found to be significantly higher after consuming carbonated drinks than after water — which the researchers believe proves the link between carbonated drinks and weight gain.

“The result of the study implicates carbon dioxide gas in soft drinks as playing a major role in inducing weight gain and the onset of obesity via ghrelin release and stimulation of the hunger response in male mammals,” they wrote.

If they’re right, it means one of the oldest dieting tricks around — “switch to sparkling water!” — could have the exact opposite effect than intended. (Mmm, taste that sweet irony.)

But an analysis of the research published by the UK’s National Health Service points out that it’s tricky to conclude that the carbon dioxide in fizzy drinks is directly responsible for weight gain.

“It is likely that obesity is caused by multiple environmental, social and lifestyle factors, rather than carbonation on its own,” says the analysis.

The study was published in February but has now gained traction after it was reported in the Daily Mail this weekend.

The British Soft Drinks Association pooh-poohed the link between carbonated beverages and weight gain, with a spokesman insisting to the Mail that “it’s bad science just to assume an outcome from a study on rats will be the same for humans”.

It’s not exactly shocking that sugar-laden soft drinks (which are basically just liquid calories) lead to easy weight gain. But it is surprising that diet and sugar-free soft drinks appear to be just as bad — even though they don’t have any calories in them.

While that weight gain could be pinned on the carbonated water in soft drinks, it could also be that people who regularly consume any kind of soft drink are also more likely to eat less healthy food and exercise less often.

Some experts offer an easy solution to the conundrum: where possible, just drink plain old calorie-free water.

image beaconimage beaconimage beacon