According to Dr Sebi, fasting is something that you do gradually over a period of time. You will adjust yourself too fast.
The first time Dr Sebi fasted, he did it for 94 days non-stop, but that is unusual for a beginner because the stomach has to adjust and get used to fasting, otherwise your body may feel the need to fill things thing back up in your stomach because it is used to keeping it full.
However, if you fast one day and eat another, fast one day and then eat another, take that for bout 7 days, then you will have an easier time fasting for multiple days. After that, your stomach will start to shrink and your desire for food decreases significantly.
In this video, Dr Sebi talks about how he fasted to reverse impotence and diabetes.