Why is glucose used as an energy storage

Your body stores extra glucose as glycogen to use when you need more energy. All parts of our body need energy to function. We get energy from carbohydrates, protein, and fat in the food we eat. During digestion, our body breaks down carbohydrates, protein, and fat into smaller pieces so our body can use them for energy. [pdf]
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Liver energy storage

Excess glucose gets stored short term in the liver and muscles as glycogen or long term as fat. Liver glycogen acts as a reservoir for your body's glucose to help maintain normal blood glucose levels. [pdf]
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