On  Science Friday recently Ira Flato interviewed Professor Susan Swithers about her research on artificial sweeteners.  You know the keywords: Splenda, Stevia, Equal, diet soda, zero calorie drinks, sugar-free gum….


These items have never been included in the Kartini meal plan and we ask our parents not to have them in the home.  Dr. Swithers now brings a relevant and interesting perspective on such super-sweet chemicals, especially in light of some of our newer metabolic tests done here in the clinic. In  Trends in Endocrinology and Metabolism July 3 2013  (see also this week’s Give Food a Chance newsletter for more media coverage of this study)  Dr. Swithers proposes that ingestion of even small amounts of these artificial sweeteners cause derangements in energy and glucose (sugar) metabolism that can lead to obesity, type two diabetes and heart disease.  Serious stuff, folks.


Basically, the problem as she sees it, is that the brain is programmed to initiate a cascade of metabolic responses to ingested sugars and carbohydrates designed to allow us to use glucose as a fuel, to burn now and to save some as fat to burn later, to feed the brain itself and to act as a trigger for other metabolites controlling mood, food seeking behavior, reward circuits, etc.  Some of the chemicals involved are insulin, glucose produced endogenously by the liver, GLP1 hormones (controlling the balance between glucose and insulin as well as appetite and satiety), leptin, and more.  


The brain orchestrates our metabolism magnificently: when the tongue senses “sweet” it knows what will follow, namely sugar.  When nothing follows, no calories, no fuel, the system is thrown off.  If this “crying wolf” happens often enough, the response of finely tuned hormones like GLP-1 becomes less sensitive and might, paradoxically, lead to unintended consequences such as weight gain.


I urge readers to listen to this interview and draw their own conclusions.  Some eating disorder centers allow diet drinks in their meal plans, no doubt partially fueled by the fact that staff may drink them.  Ditto zero-calorie drinks.  They have been promoted as anti-obesity “healthy choice” options for school children as well.


Be careful with children, be very careful.