In fact, the burning of fat will not be felt. Whether fat or thin, people will consume energy when they are alive. After inhaling air, blood will be oxidized first, that is, hemoglobin will carry oxygen and flow all over the body. In this process, blood will be reduced, specifically, iron ions in blood will change from trivalent to bivalent (chemistry should be studied in senior high school), while other parts of the body will undergo oxidation reaction and release heat.

The so-called combustion process is actually a metabolic process and is imperceptible. Our human body is burning, and infrared instruments can tell.