Conclusion
As you can see, there is a big difference between the internal machinery of those that fast occasionally and those that don’t. These differences can very much be the difference between a long, healthy late life and a short, sick one. This is because our bodies were designed to react to and thrive in conditions of zero calorie intake periods rather than in a chronic energy surplus. Fasting is effective in restoring insulin sensitivity to resistant cells as well as increasing the efficiency of energy distribution so that you no longer store unneeded fat.
Although my example included someone fasting for at least a week, there are more sustainable strategies. For example, by eating all your food within a daily 4 hour period, you can slowly burn off your liver glycogen and fat, provided that you eat few enough calories each day. This fulfills the psychological need for food as well as providing health benefits. Ultimately, the message I want to convey is simple: when looking at health issues, take a step back and ask yourself what we evolved to do. More often than not, this will provide the answer you seek.