The diet is an integral part of all yogis, swastha purushas, and the healthy persons or diseased.We studied the principles, components, physiology, pathology, and management of diet in the Yoga, the Ayurved, and the current WHO standards On comparison and summarization, we found- Research parameters leans towards more subjective while choosing the diet material; but the diet principles become more philosophical while choosing the diet habits. So is true about understanding the body, the nature and the balance, the interactions between them. Under the parameters like expected effects or ultimate aim the body constituents, theories, and medium of transmission of power determines ‘the path’, and so the form of diet, therapy vehicles, and criteria of health etc. So, the diet should be watched as philosophical entity to know or to aim at whilst proper materials are imperative to transfer specific thoughts.