As a yoga practitioner you need to understand that the yoga diet has proved to be one that builds the body and keeps it healthy. The correct kind of food eaten in the correct quantity nourishes not just the body but the mind and the emotions too. In India it has always been believed that what you eat reflects your personality. This is why in yoga food is an important part of yogic practice as important as asana, pranayam and meditation.
Yogic food is vegetarian because those are the foods that keep the body light and the mind clear to pursue spiritual growth. The traditional Ayurvedic diet is composed of different diets based on different constitutions. However, the great sages of yoga believed that the yogic practitioner is capable of selecting those foods that are needed by the body. In keeping with the yogic belief of non-violence and also the belief that non-vegetarian food hinders clear thinking, non-vegetarian diet is shunned.
Since all yoga traditions, across the spectrum, believe that food is very much a part of yogic philosophy as a yoga teacher you too must understand what kinds of food help in spiritual development besides keeping both the body and mind healthy. What you eat will impact how well you do at your yoga practice as food feeds the mind as well as the spirit.