This work investigates the foundational principles of ancient Greek nutritional science and the physiological effects of various foodstuffs on the human body. Galen, a prominent physician and philosopher of the Roman Empire, synthesizes his clinical observations and humoral theory to categorize foods based on their inherent qualities. By examining the interaction between diet and health, the text provides a systematic framework for understanding how specific ingredients influence the balance of bodily fluids. The author utilizes his extensive medical background to argue that dietary regulation is the primary mechanism for maintaining physical equilibrium and preventing disease.

Historians of medicine regard this text as a critical primary source for understanding the development of Western nutritional theory. Scholars frequently note the dense, technical nature of the prose, which reflects the rigorous medical standards of the second century.