A prolonged fast has additional benefits compared to an overnight fast. Overnight the body still has liver glycogen and is not forced to begin burning fat. However, after two days of fasting, or a fasting-mimicking diet, the body starts to burn visceral fat as energy. The brain stops using sugar and begins using ketone bodies, such as beta-hydroxybutyrate as fuel. Further changes are seen, as the immune system, and organs including the liver and the heart shrink. In this clip, Dr. Valter Longo explains the benefits of a prolonged fast.
This clip was taken from the first FoundMyFitness interview with Dr. Valter Longo found at https://www.youtube.com/watch?v=d6PyyatqJSE
Original episode published on Oct 1, 2016