Drinking diet fizzy drinks but struggling to lose weight? You might not be alone. New research suggests that low-calorie ‘sugar free’ versions of soft drinks might actually prove to be a hindrance for those looking to shed some excess weight. However, a sweetener used in these types of drinks (aspartame) may be the main culprit in people’s struggle in shedding the pounds. This is according to research by Massachusetts General Hospital, which suggests the sweetener is interfering with the body’s metabolism. Using mice as test subjects, researchers discovered that contained within aspartame is a product known as phenylalanine, which disrupts an enzyme. This premise is similar to something that is seen in people with type 2 diabetes or heart disease. The lab tests also revealed that mice with aspartame in their drinking water gained more weight and encountered more problems with metabolism compared to the mice that didn’t consume the sweetener. “Sugar substitutes like aspartame are designed to promote weight loss and decrease the incidence of metabolic syndrome, but a number of clinical and epidemiologic studies have suggested that these products don't work very well and may actually make things worse,” the report's senior author Dr Richard Hodin commented. “We found that aspartame blocks a gut enzyme called intestinal alkaline phosphatase (IAP) that we previously showed can prevent obesity, diabetes and metabolic syndrome. “So we think that aspartame might not work because, even as it is substituting for sugar, it blocks the beneficial aspects of IAP.” However, The British Soft Drinks Association argued against the claims of the paper. Gavin Partington, BSDA Director General, said: “These claims are being made by a study conducted on mice and run contrary to the overwhelming body of scientific evidence. “Decades of scientific research, including human clinical trials, show that low-calorie sweeteners, such as those in diet drinks, have been found to help consumers manage their calorie intake when part of an overall healthy diet.” The issue of fizzy drinks is clearly one that is not going to disappear anytime soon. Earlier this year Medical Specialists® Pharmacy reported how the drinks have been linked to fertility and erectile problems, whilst there have been repeated calls for a sugar tax to be implemented, ranging from anywhere between 20% to 50%. It could be worth trying to cut down on the fizzy drinks if you are trying to lose weight. Moreover, Medical Specialists® are able to provide help for those still trying to lose weight, with our fantastic range of obesity treatments such as Xenical and Orlistat. Used in conjunction with a balanced diet and exercise, these treatments are very effective in enabling people to lose weight and gain back confidence.