First person, Adam and Chava were vegetarian.  So why aren’t we? The reason is because when we eat with humility, enunciating a bracha and using the food energy constructively, we elevate the soul of the plant and animal. Notes:
• Many people adopt vegetarianism and veganism as a true expression of their gentle nature and sensitivity to the animal’s life. Such genuine kindness is to be admired and emulated. And, as we read in this week’s parsha, Bereishit, Adam and Chava were indeed vegetarians.
• So why aren’t all practicing Jews vegetarians? Why were the generations after Noach and the flood permitted, by the same Torah that forbade Adam and Chava, to eat meat?
• The world is made up of four levels: human, animal, plant and inanimate. The animal kingdom, being the proximate level to human, was subject to human exploitation. Human arrogance and ego needed to be trained and tempered not to do so, so the animal kingdom was forbidden as a source of human food.  
• But the purpose of creation si for the human to elevate the world.  We spiritually elevate the plant or animal food by consuming it, not for mere satisfaction, but if done humbly and spiritually through a brachah and positive Kavvanah,  we transform the animal or plant vitality  to a higher spiritual plane. The plant is lifted.  The animal is lifted.
• After the flood humankind was ready to do so. Whether you are a carnivore or vegetarian/vegan – be aware that eating food is a holy act of elevation, a privilege, to be done consciously and sensitively.