When you have a chronic energy deficit (fewer calories coming in than going out), over time your body starts thinking that food is scarce. This results in your body holding on to fat as a way to protect itself. To make an analogy, think of your body like a house. If you’re not making enough money to pay your house bills, what do you do? Well, you may turn down the heat in your house, turn off lights when you are not in the room, and perhaps even fire your cleaning lady to compensate. Your body operates in a similar way. When you do not have enough calories coming in, your body saves energy by reducing your body temperature (slowing your metabolism), turning down your digestive juices (making your digestion weaker), reducing your pulse, and slowing your thyroid function (resulting in less energy). These are all built-in survival responses by your body, to help you go longer on less food.
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