I know diet soft drink like diet Pepsi etc is not allowed when fasting, even if they contain no calories. It has something to do with insulin? I don’t quite understand it though. Can someone explain like I’m five?
The way I understand it is that the sweetness triggers an insulin reaction so your body expects food, but isn’t getting it. This in turn triggers your eat now hormones so you start to get hungry. Read The Obesity Code by Dr. Fung, he explains it very well.
The way it’s been explained to me is that, even though diet soda doesn’t have the calories associated with standard soda, the sweetness on your tongue can trigger cravings for actual sugar or make you prefer sweeter foods. So it acts as a “gateway” to sweeter and more calorie-dense but nutritionally empty food.
I haven’t seen any scientific papers backing that up, which is not to say that they don’t exist but to caveat that what I’m telling you is hearsay.
Here’s an article on low calorie sweeteners which you might find useful.
I’ve done loads of extended fasting and drank stevia sweetened sodas the whole time.
I just stay away from diet sodas because I’m afraid of all the unnatural ingredients and aspartame supposedly damages your gut.
But I might just be brainwashed. If you don’t care about that stuff there’s no reason you shouldn’t be able to drink diet soda.
Off topic but have you tried flavored sparkling water instead? Don’t get me wrong, I love a good Coke Zero mid-fast but I’ve found that Aha and Bubly brands Sparkling Water are pretty delicious and have the same effect. There are even caffeinated ones!!