To understand the answer, it helps to remember that fat is basically stored energy. Your body converts fat to usable energy for your muscles and other tissues through a series of complex metabolic processes. This causes your fat cells to shrink.
These metabolic activities also generate heat, which helps maintain your body temperature, and waste products. These waste products — water and carbon dioxide — are excreted in your urine and sweat or exhaled from your lungs.
Apr. 28, 2012
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