
I am a research geek by nature. This whole thread sparked my interest.
Warning! Could be very boring! Ignore if you want.
I once had an anatomy and physiology professor tell me digestion starts at the mouth with the release of amylase. I also remembered that you didn't have to swallow to actually get digestive enzymes started. So it made me wonder what else could happen especially in relationship to glucose metabolism.
Anyways, after doing a little research I didn't find anything right off hand of just pure taste per se (no consumption), but I did find an interesting article about the ingestion of diet soda (the artifical sweetener sucralose -Splenda) and the effects on a little known hormone that plays a role in glucose metabolism.
Ingestion of Diet Soda Before a Glucose Load Augments Glucagon-Like Peptide-1 Secretion Interestingly, the artificial sweetener
did not play a significant role in increasing either insulin or glucose, but it did increase this one hormone, which is a glucogon like hormone. If you are wondering what the heck is glucogon, it is basically a hormone that works to raise your blood sugar, the opposite of insulin. The hormone is found in both gut and tongue tissue.
Ok now you all are wondering how this is vaping related. It may not be, but in my little racing mind it makes me wonder, what the sweet taste of some e-juices might possibly be doing to the glucogon like hormone receptors or other hormones in all of our tongues and subsequently our metabolism and weight. Mind you that all of our metabolisms are different because of genetics, diseases like diabetes etc. So there are many other variables, but I found this intriguing enough to share with the masses who are interested in this type of thing.

We probably will not know until science/government stops arguing whether or not this is a healthy thing and actually starts doing some unbiased research. That's the problem when you throw morality around.