Sugary drinks can cause weight gain and long-term health problems if drunk regularly for as little as a month, according to scientists.
Too much fizzy pop or sweetened fruit juice alters the body’s metabolism, so that the muscles use sugar for energy, instead of burning fat, a study found.
The effect is long-term, making the pounds harder to shift and raising blood sugar levels, which increases the risk of conditions such as type 2 diabetes, it was claimed.
Dr Hans-Peter Kubis, who led the research at Bangor University, said: “Our results give a stark warning against regularly drinking sugar-sweetened drinks.”
He added: “Not only can regular sugar intake acutely change our body metabolism; in fact it seems that our muscles are able to sense the sugars and make our metabolism more inefficient, not only in the present but in the future as well.
“This will lead a reduced ability to burn fat and to fat gain. Moreover, it will make it more difficult for our body to cope with rises in blood sugar.”
Dr Kubis said that, when in need of refreshment, people should drink water instead.
His researchers found that the muscle cells of volunteers both identified and responded to a sugary diet, switching how they used the fuel. This created an inefficient metabolism in lightly active men and women who drank fizzy beverages on a regular basis for four weeks.
Dr Kubis added: “What is clear is our body adjusts to regular soft drink consumption and prepares itself for the future diet by changing muscle metabolism via altered gene activity, encouraging unhealthy adaptations similar to those seen in people with obesity problems and type 2 diabetes.”
In the study, 11 people in their twenties supplemented their diets with sugary soft drinks for a month. Before and after the study they had their blood and muscle tissue, as well as their whole body metabolism and composition, tested.
Genes and proteins important for fat and sugar metabolism were analysed and blood sugar and fats assessed.
Dr Kubis said: “What we found is that it is not the sugar in itself that puts on weight but the way it gets the body to store more.
“This would relate to all kinds of soft drinks with a high sugar content, including fruit juices.
“It was a small study because it is difficult to find young people who have not previously been exposed to a lot of soft drinks and who are willing to undergo muscle biopsies.
“But we are now hoping to carry out a bigger study with more participants over a longer period of time.”
Dr Kubis has been campaigning for the Government to take action to encourage the public to cut down on sugary drinks.
He added: “Clearly taxation on sugary drinks is overdue. This money could be invested in the NHS where it is urgently needed to treat people with obesity problems and diabetes.”