how does your body burn up the food you eat?
Food is fuel and fuel burns. But where is the fire?
The fact is that burning can be either fast or slow. A log in fire can burn very fast. As it burns, the different chemical combinations in the wood shuffle around. Some of the chemicals join with oxygen from the air. In a little while the whole log has changed and dissappeared, except for few ashes. Some of the wood chemicals are also in food. they too, change and join with the oxygen that you breathe into your body. But the shuffling goes on a little at a time. It warms you without making a glow like a fire.