I see people are chiming in with their own experiences with IF, so here's mine: I've been doing IF for about 4 months myself and it's done wonders for me and positively changed my lifestyle. I lost weight much easier than ever before, but it's hard to tell how much of that is because of IF itself and how much is due to the dietary changes I implemented at the same time (zero processed food, significantly reduced sugar intake, etc...).
However, the biggest benefit I got from doing full IF is that it's become much easier for me to go without food for longer periods of time. I noticed this particularly on my most recent business trip, where I'd planned to travel for 6 hours starting at 6 AM with a rather hectic itinerary and several changeovers, so there wouldn't have been enough time to stop for snacks. When I arrived at my destination, I realised that I'd woken up, ate nothing, and then spent 6 hours on the road without even having thought of food.
I also noticed that it's become possible for me to switch from an eating-for-pleasure to an eating-for-sustenance mode without having to struggle with cravings and trying to suppress them.
My entire plan was as follows:
First I spent 6 weeks avoiding all sugar, just to reset my tolerance, so to speak. This was by far the hardest part. At the same time I got myself a so-called "multi-cooker", which is basically an air fryer and pressure cooker combo, because it seemed to me that it would make cooking and preparing large quantities of healthy food easier (that did prove to be the case).
At the same time, I started IF by allowing myself to eat only between 9 AM and 1 PM, unless I don't have access to food during that window (for example because I'm travelling and didn't have time to prepare food for the trip). Initially, I still counted calories when I ate even during that window, but then I noticed it was becoming effortless for me to not overeat. As long as I didn't introduce unhealthy food into the diet, calorie counting was no longer needed. In fact, I swung so much the other way at one point that I had to make sure I was getting enough food into my stomach during that four-hour window. I only ate one or two meals at most a day.
I was already working out regularly before IF, but it wasn't enough to maintain a healthy weight and make me feel energetic overall. I realised that after making changes to my diet.
After a while of doing IF, I started relaxing the rules a bit, especially with regards to what I'm not allowed to eat. However, I made sure to measure waist circumference and overall weight at least once a week and to take corrective measures as needed. I found that I'm able to have a chocolatey treat once or even twice a week, but still maintain a healthy weight. I still fast every day, but sometimes I extend the meal window to, say, 3 or 5 PM. I think that finding this balance after the initial period of culinary deprivation is an important final step in the journey, and is not to be underestimated. This was perhaps the second-hardest bit after quitting sugar abruptly (the withdrawal was real, albeit brief).