Our body is constantly fluctuating and changing and for the most part this is normal. A good metabolism is like a well-kept engine and will function in the right way, quickly adapting to situations as they arise. For example, when we go without eating for extended periods of time, we get hungry, we then eat, and this causes our levels of glucose to go back up.
If food intake is limited and intervals too spread out, our metabolism gets out of control and our engine starts working out of sync. Once our body senses that we do not have access to food, it will send a stress signal to our liver which will then overcompensate by releasing a very big dose of glucose. Now, the body has too much glucose which will then cause it to send out another stress signal in order to stabilize the glucose levels. To this, our pancreas will respond by releasing large amounts of insulin, of which too much can cause your blood sugar levels to plummet, hence the “crash.”