Well, you see, when you ingest a high amount of sugar, your body enters ketosis and speeds up your metabolism unless you are low on glycogen reserves. Your increased metabolism then processes that sugar, which puts you in a "sugar high" state. If you don't have a lot of simple fats or polysaccharides in your body at that point, it causes a false sense "hunger" for calories as you enter a sugar "low". Thus, a viscious cycle is born.
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