In a nut shell you start the program with 9.5 days of ULC (ultra low carb) days - 30 grams max a day. On the 10th day, starting around 3 or 4 p.m. you begin your Carb Nite. You have a 6-8 hour window where you can eat just about anything you want. The next day you go back to ULC and no sooner than the 5th night after you have another Carb Nite - one Carb Nite a week.

There is a book and more info can be found here. The book is about 10 years old, so lots of the info has changed, but the basics remain the same. An updated version is in the works. You can also find lots of podcasts by John Kiefer on YouTube and www.body.io.

I was afraid that the Carb Nites would trigger cravings but they have not.

In fact, knowing that on Carb Nite I can have whatever I want has actually prevented me from caving in to the call of the carbs (i.e. Chinese food, popcorn, etc.). For me personally, I believe I have finally found my lifelong way of living.