diet soft drinks

Low-calorie drinks only create an increased risk of type 2 diabetes if a carbohydrate is added to the beverage, according to an American study.

Researchers from Yale University tested the theory that consuming low-calorie sweeteners disrupts the human metabolism, therefore creating an increased risk of developing obesity related conditions.

They posed this question and set out to find the answer in a bid to put to bed the long-standing debate over low-calorie sweeteners, like sucralose, in foods and beverages.

In the past, there have been conflicting results into the effects of consuming low-calorie sweeteners. Some studies have suggested that they promote the development of type 2 diabetes and obesity by disrupting the human metabolism. However, research has also found that consuming low-calorie drinks and food actually has a limited impact on metabolism, with research even saying they can actually aid in weight loss.

The findings of this new investigation surprised the researchers. After participants trialled different drinks over a week, it was found that those consuming a low-calorie sweetener only experienced negative metabolic responses when it was combined with a carbohydrate.

In short, combining low-calorie sweeteners with other carbs and sugars can cause insulin sensitivity to drop, which increases the risk of type 2 diabetes. Additionally, the researchers discovered that there were no changes in brain or metabolic responses to sugars when drinks containing low-calorie sweeteners alone were consumed.

Professor Dana Small is the director of the university’s Modern Diet and Physiology Research Center and was a senior author on the study. She said: “The bottom line is that, at least in small quantities, individuals can safely drink a diet soda, but they shouldn’t add French fries.”

“The subjects had seven low-calorie drinks, each containing the equivalent of two packages of Splenda, over two weeks. When the drink was consumed with just the low-calorie sweetener, no changes were observed; however, when this same amount of low-calorie sweetener was consumed with a carbohydrate added to the drink, sugar metabolism and brain response to sugar became impaired.”

The study tested the theory that the consumption of sweet foods and beverages not containing calories “uncouples” sweet taste perception from energy intake, which then goes on to reduce physiological response to sugar. This is associated with weight gain, glucose intolerance and the development of type 2 diabetes.

Limitations to the study should be considered due to the small sample size and short duration. However, the findings provide an interesting avenue for further research to explore in depth the effects of low-calorie sweeteners.

The study was published in the journal Cell Metabolism.

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