Energy and Body

Starting from the physical definition of energy, this chapter presents its significance for the human body. Since a human being, from an energy perspective, represents an open system that absorbs energy through food and loses it again in various ways, the human body requires energy storage and controlled energy release. The main storage organs are the adipose tissue and the muscles. Storage and release are regulated by endocrine glands, neuronal pathways, and cytokines—the latter are messenger substances of immune cells. Thus, we can clearly distinguish between storage factors and release factors. This chapter presents these important factors in detail. The chapter is challenging, but it is the important platform for the entire book.