I'm not sure how I feel about this.
For the past 6 months or so I'm more or less in a routine of doing a 24-hour (or more) fast per week. The main reason I'm doing this is because ketosis urinalysis strips are telling me that somehow a diet of no carbs but green vegetables somehow lessens my keto levels around a certain point, and only a total fast ensures going farther into ketosis. So, I'm mostly doing it to maximize my ketosis diet that's had me steadily losing weight for a long time now (had quite a bit to lose, unfortunately).
Beyond that, I THINK I can testify to other healing effects and mental clarity and I think recovery from lasting effects of stress.
Some things I hear about intermittent fasting, though, I can't get on board with from my personal experience before and after I heard about it. Firstly, I believe in the "old" science that says going very long without eating for too long slows down metabolism and conserves calories, and so giving the body any kind of burst of calories (like the one meal a day thing) will result in fat storage just because there's nothing else that can happen to them and in response to a potential starvation situation. That's just been my experience. I've always found that fat loss happens the most with eating smaller meals (mostly lightening up on high-glycemic carbs), which I suspect triggers mechanisms for food SCARCITY (we're rationing our food stores in times of less supply, like in a winter season), not full-on starvation.
And, all that has me feeling the most decent too. I can't get on board with the OMAD thing pretty much for sure. The other thing is, I also can't second-guess that my BEST workouts lifting weights would happen after a big sandwich on a whole wheat bun -- NO way I need to keep finding that out to be convinced. There's nothing like the energy of being carbed-up, including mental sharpness too. The trick is getting away with that of course: metabolism.
I flat-out don't believe fasting is good for a direct approach to fat loss. Again, the only benefit I see is to beeline it to ketosis, but fat burned in a fast can't offset the negatives of damage to metabolism. But all these other benefits like autophagy, starving cancer cells, and more, sure make me want to go for longer fasting periods more frequently. I've heard varying things about benefits from different sources. I've made it to 36 hours but usually go about 24 and still often get anxious and can't function well after that point.
Thougts?