I distinctly remember the concept of digestion beginning in the mouth as a main theme of one of my general nutrition classes in college. As my education progressed and I learned more about the biochemistry of how food is broken down, it was confirmed that indeed our taste buds signal our endocrine system that food is on the way.
So what happens when the tongue tastes the sweetness of sugar but the body does not actually receive any sugar or carbohydrate? My hypothesis has always been that the pancreas would begin to secrete insulin, blood sugar would decrease and, in turn, the body would be left to crave the sugar it did not get.
I often saw this anecdotally when I would suggest to my clients who struggled with overeating or binging to decrease diet soda and artificial sweeteners. Some of my clients noticed little change in sugar and carbohydrate cravings, but the majority did observe fewer cravings. The change seemed to mostly impact those who tried to drink diet soda as a replacement for meals or snacks.
Whenever I have given the summary of my hypothesis about diet soda, I have had to add the caveat that I had no research to actually support my theory. Well, now that research seems to be surfacing.
Studies in the Journal of Trends in Endocrinology & Metabolism have shown that diet soda drinkers suffer many of the same health problems of those who drink regular soda. The journal Appetite also published a 2012 article describing how rats given the artificial sweeteners saccharin and aspartame had — in both instances — greater weight gain than those given sugar. In 2010, Appetite also noted that aspartame causes more insulin release than sucrose 30 minutes after consumption.
No study has yet to prove my hypothesis beyond a doubt. However, I think it is safe to say that we may want to consider approaching diet soda in a way we approach many other sweet treats. They should be had only in moderation. I personally am a fan of suggesting they be added to a meal or snack that contains carbohydrate, protein and fat. That way, the body is being fed some carbohydrate rather than just being tricked into thinking it is getting the glucose it may be prepared to receive.