The queue in any popular fast food chain will often include customers walking away with a tray full of fried food and a diet drink on the side. Whether this is a nod by the consumer to healthy eating or whether it is a true preference for the sugar free drink itself, I’m not sure. Diet drinks have such strong branding these days that it is sometimes difficult to differentiate the exact reason why people drink them. However, what is clear is that there is definitely a large category of people who drink them because they are low in calories and are believed to contribute to weight loss. However, rather counter intuitively these sweetened drinks are often not associated with weight loss and sometimes are indicated to cause weight gain.
The sweetener used in many of these drinks is called aspartame. This will not be a new word for most people, as it has been in the spotlight for some time for its apparently deleterious effects on human health. I have seen aspartame linked to multiple diseases and at one stage it seemed impossible that it wouldn’t be banned by the FDA or EMEA. However, the scientific evidence has been contradictory and I have abstained from having an opinion on it for some time. One study which I found in support for the “against” camp, published in 2016 in the journal Applied Physiology, Nutrition, and Metabolism caught my attention.
In 2013, it was demonstrated in mice that the gut enzyme intestinal alkaline phosphatase (IAP) was shown to prevent obesity, diabetes and metabolic syndrome (combination of conditions such as high cholesterol, bloody pressure etc). Interestingly, later research conducted by the same group found that aspartame inhibited this same IAP enzyme. When 2 groups of mice were fed on a high fat diet, and one group was given plain water and the other water supplemented with aspartame, the aspartame group had higher blood sugar levels and gained more weight. High blood sugar levels is an indication of glucose intolerance and diabetes while weight gain obviously underlies obesity .
Therefore, this work may help to explain some of the detrimental effects associated with aspartame and may just sway me towards leaving it out of my morning coffee!
 K. Kaliannan, S. R. Hamarneh, K. P. Economopoulos, S. Nasrin Alam, O. Moaven, P. Patel, N. S. Malo, M. Ray, S. M. Abtahi, N. Muhammad, A. Raychowdhury, A. Teshager, M. M. R. Mohamed, A. K. Moss, R. Ahmed, S. Hakimian, S. Narisawa, J. L. Millan, E. Hohmann, H. S. Warren, A. K. Bhan, M. S. Malo, R. A. Hodin. Intestinal alkaline phosphatase prevents metabolic syndrome in mice. Proceedings of the National Academy of Sciences, 2013
 Sarah Shireen Gul, A. Rebecca L. Hamilton, Alexander R Munoz, Tanit Phupitakphol, Liu Wei, Sanjiv K Hyoju, Konstantinos P Economopoulos, Sara Morrison, Dong Hu, Weifeng Zhang, Mohammad Hadi Gharedaghi, Haizhong Huo, Sulaiman R Hamarneh, Richard A. Hodin. Inhibition of the gut enzyme intestinal alkaline phosphatase may explain how aspartame promotes glucose intolerance and obesity in mice. Applied Physiology, Nutrition, and Metabolism, 2016