Sugar-free and diet drinks are not helpful for weight loss and could even cause people to pile on the pounds, researchers at Imperial College have claimed.

A review of dozens of studies dating back 30 years found that there is no solid evidence that sugar-free alternatives prevent weight gain, type 2 diabetes or help maintain a healthy Body Mass Index. (BMI)

Although artificially-sweetened beverages contain fewer calories than sugary versions, researchers say they still trigger sweet receptors in the brain, which may make people crave food. Coupled with the fact that most people view diet drinks as healthier, it could lead to over-consumption, the researchers argue.