It's about good fats, and not about depriving yourself. You choose what level of commitment you want to follow. I start my day with a cup of coffee and blended into the coffee is 1 tablespoon of grass fed organic butter and 1 teaspoon of unrefined coconut oil. Yes it sounds icky but it is actually not much different that adding cream to your coffee and it keeps me going until lunch time with no hunger. That's what I mean by good fats. My body is using up the fats instead of storing them because I did not give it carbs for breakfast, like a granola bar, cereal, or yogurt. There is no "cheating" because that's not the thought process behind this diet ie eating habit. There are days when your body will tell you to eat carbs because you need it not because your mind says "it's snack time, grab a candy bar". Now this doesn't mean you need to hit McDonald's for a combo meal, make good carb choices.
It did take me about a week to skip the afternoon snack that was a habit not a need but now I don't even miss it. I have dropped 11 pounds in 2 months time and like I said, I'm only about 90% bulletproof because that is the current level of comfort for me. I am choosing to be a healthier person not because I have a health issue right now but because I don't want to have one in the future.
Check out the blog for how to get started and don't just take my word for it, my other half (more disciplined half); Gabe, has lost 18 pounds in the first 45 days and he has only just started adding exercise back into his routine now that he has adjusted his eating habits. Here is a link to the blog, https://blog.bulletproof.com/the-complete-illustrated-one-page-bulletproof-diet/. Happy Health!