First time attempting 48 hour fast-What's the scoop on sparkling water?

I’m currently 19.5 hours into my first time doing a 48 hour fast, and feeling pretty good! I used to practice OMAD very regularly and had great results, but fell off the wagon in the last several months after a couple job/lifestyle changes. I used to work a very active job and hit the gym regularly and now have a completely sedentary job, and started slacking on the gym, and it’s been rough. I’ve gained about 15lbs in that time.

But NOW, I have a better state of mind about the effects of fasting, other than only for weight loss. I started doing a lot of research about reaping all the different benefits of fasting and felt compelled to start a 48 hour fast. I’ve done many successful 24s in the past, so I know I can handle this. Before, I considered myself a more casual OMAD’er but this time, I am seeking the best results possible!

This brings me to my question: what are everyone’s thoughts on sparkling water? I feel like I keep seeing mixed opinions on this. Is it okay? Does an unsweetened flavored water break a fast? I thought it was okay, but I keep running across comments on old posts stating that it hinders your fast. Thanks!