what happens when the body uses its fat stores to provide tissues with energy during fasting, when there is not enough food energy?

When the body uses its fat stores to provide tissues with energy during fasting, a process called lipolysis occurs. Lipolysis is the breakdown of stored fat into fatty acids and glycerol, which can then be used by the body for energy. The fatty acids are broken down further into molecules called ketone bodies, which can be used by the body for energy.