Earlier quoted context omitted.
I abstain from food between 8PM and 12PM Monday - Friday, adjusting for training schedules and such. It really helps me keep my GI tract clear, reduces inflammation, resulted in weight loss, etc. without any effect on my cycling fitness. IF (or IMF as some people call it) is amazing.
I've fasted from ~8P to ~3P every day for coming up on 2 years and apart from making me more mindful of what I eat and drastically reducing my appetite I've experienced basically no other health benefits. IF is increasingly well studied and it is not especially amazing. (I like it a lot. Just saying.)
With that regime I have constant energy without ups and lulls. It's great.
When I do go too long without eating, I feel fine and I don't feel particularly hungry. But people around me say that I become uncommunicative, quarelsome, and that I tend to just kind of sit there and stare in front of me unmovingly.
People particularly notice this at group dinners/brunches. Before food, I reply with 1-word answers and mostly don't engage in conversation. After food I'm the life of the party.
So yeah, fasting does not work for me. But I do tend to have very small breakfast. At 10am regardless of when i wake up.