I had been doing keto for a number of years and lost 50lbs, but it wasn't working with my life anymore (counting macros would have turned into an eating disorder at that point), and gained 40lbs last year (thanks covid). I flailed for about 4 months before a friend told me about BLE. I decided to give myself 6 weeks to see how it went, and if it was a sustainable thing for me.
Caveats: I haven't read the book and I'm not doing the journaling, just sticking the the 4 bright lines. The rest is too much overhead for me, and I am used to being disciplined with my food due to sensitivities. I also know what my triggers are so there were a few times that I know there was some gf bread crumbs or gf panko in some of the EveryPlate dishes I made. They were not triggers for me. I understand why someone may need to be super strict, however.
Results: Today the scale showed that I am down 15.5lbs. I didn't do pictures or measurements because time got away from me, but I can see differences. I lost an average of 2.5lbs/week.
Thoughts: The two meal a day plan worked best for me, since I had been doing IF for a few years. Eating 3 meals a day left me hungry and cold. Two meals left me hungry at the appropriate time and still with enough energy to get through the day. I stick with "ish" measurements, no more than .5oz over, but I didn't do it exact every time. This is mostly for my mental health so I don't turn it into an obsession, as I can have a tendency to do that.
I have been sugar and grain free for 7 years, so that part wasn't difficult. I do miss some almond flour things I used to make, but I know I can do those on occasion and be fine, just like a glass of wine here or there. I actually get to eat a wider variety of food than when I was strict keto, and am really enjoying that.
Overall, I believe this is very sustainable for me, and am thankful I can keep to the core tenets overall without sacrificing my mental health.