I think it is important to understand metabolism. Metabolism is the process by which your body converts what you eat and drink into energy. Even when you're at rest, your body needs energy. The amount of energy your body needs to perform basic life functions is called Basal Metabolic Rate. Everyone has a different BMR and it is based on factors like your sex, age, amount of physical activity, etc. e.g. Men naturally burn more than women. However, these basic life functions take up about 70%of your energy needs.
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