Autophagy (which directly translates to self-eating) is a term that is often associated with fasting and longevity. This is a self-preservation process whereby the body removes dysfunctional cells and recycles parts of them for usage in cellular repair and cleaning. 

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This basically tells us that if you stop eating for a certain period of time, or significantly lower your calorie intake through fasting, it deprives the body of nutrients, which forces it to repurpose cells in order to function. In fact, a 10-40% reduction in overall calorie intake is one of the most effective ways to induce autophagy, with it occurring within 18 – 96 hours. 

Autophagy isn’t the only bodily process induced by fasting. When you fast, your body goes through a process of ketosis.

Ketosis is the process whereby your body doesn’t have enough carbohydrates to burn for energy, so it burns body fat instead, leading to the formation of ketones, used for fuel. Through this process, the body begins to lose essential electrolytes such as sodium, magnesium, potassium, and calcium. When this happens for an extended period of time, it can lead to unpleasant side effects. This can then make fasting a health risk if not done correctly.  

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