Where is glycogen mostly stored in the body?

Glycogen is primarily stored in the liver and muscles due to their critical roles in energy metabolism. In the liver, glycogen acts as a glucose reservoir, providing a quick release of glucose into the bloodstream to maintain blood sugar levels during periods of fasting or increased energy demand. This function is essential for overall energy homeostasis.

In muscle tissue, glycogen serves as a readily available source of glucose during physical activity, providing energy directly to the muscles as they work. When muscles contract, they break down glycogen into glucose, which is then used in cellular respiration to generate ATP, the energy currency of the cell.

The other locations mentioned—kidneys, pancreas, heart, brain, skin, and bones—do not serve as significant sites for glycogen storage. While the brain does utilize glucose extensively as its primary energy source, it does not store glycogen to the same degree as the liver and muscles, making the liver and muscles the predominant storage sites for glycogen in the body.