Final answer:
The three metabolic states of the body are the absorptive state, postabsorptive state, and fasting state. Insulin regulates the absorptive state, while glucagon and other catabolic hormones regulate the postabsorptive and fasting states.
Step-by-step explanation:
The three metabolic states of the body are the absorptive state, the postabsorptive state, and the fasting state. In the absorptive state, also known as the fed state, the body is digesting food and absorbing nutrients. Insulin is the hormone that regulates this state. In the postabsorptive state, the body is using stored energy to meet its needs. Glucagon is the hormone that regulates this state. In the fasting state, the body is relying on its stored fat for energy. Glucagon and other catabolic hormones are responsible for regulating this state.