All it takes is one can of soda to increase risk of type 2 diabetes by 22%, according to a new study.
In the study published in Diabetologia, researchers studied diet and drinking habits of about 28,500 people from Britain, Germany, Denmark, Italy, Spain, Sweden, France, Italy, and the Netherlands over a period of 15 years.
Those who consumed a 12 oz serving of a sugared-beverage on average daily — about the size of a soda can — had a greater risk of developing diabetes compared to people who drank a can once a month or less.
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The results are in line with other data from the U.S. that linked sugar-sweetened beverages like sodas and fruit juices with an increased risk of heart disease and diabetes. But the relationship is still an association, and does not establish that sugared beverages cause diabetes.
The reason for the connection reflects the complex interaction among eating habits, body weight and other metabolic factors that contribute to the disease. In the current analysis, for example, the increased risk of diabetes only appeared among those drinking sugared sodas daily, and not among those who consumed fruit juices. But the association remained even after the scientists took into account the participants’ body mass index (BMI) and the total amount of calories they ate in a day, they still recorded an 18% increased risk of type 2 diabetes among the frequent soda drinkers.
That suggests that the contribution of sugared drinks to diabetes risk may extend beyond its effect on weight — the researchers found that even those who drank artificially sweetened soft drinks appeared to show an increased risk of diabetes, which disappeared once they adjusted for the influence of weight. People who drink sugar-sweetened drinks may not be healthy overall, and have other risk factors that contribute to their increased vulnerability to developing diabetes, say the researchers; for example, overweight itself is a risk factor for the disease.
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The findings are likely to fuel a currently contentious debate in New York City, where they have been the target of a public health campaign by New York City Mayor Michael Bloomberg in recent months. As part of the mayor’s ongoing efforts to improve the health of New Yorkers, Bloomberg proposed a ban on super-sized sugary drinks that would have prohibited restaurants, delis, sports arenas, movie theaters and food carts regulated by the city health department from selling drinks larger than 16 oz. However, a judge blocked the ban the afternoon before it was implemented, calling it “arbitrary and capricious” since it would not apply to all vendors equally.
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Both the American Diabetes Association and the American Heart Association (AHA) recommend that people limit the number of sugared sodas they consume, and the AHA says women should try to restrict the added sugar they drink to no more than 100 calories per day, or about 6 teaspoons of sugar, while men should consume no more than 150 calories, or about 9 teaspoons of added sugar daily.