Vegetarianism is perhaps the most popular alternative diet on the planet. Many of its adherents have adopted the practice for philosophical reasons, such as concern over the treatment of modern farm animals or because they feel the diet is more environmentally conscious. There are also many who are vegetarian for religious reasons, and a large number who are no longer eating meat because they feel it’s the health-conscious thing to do. A number of vegetarian sources promote the diet as one that reduces the overall risk of heart disease and cancers while providing more energy in the short-term.
Human beings have evolved to be suited for an omnivorous diet, that is one containing both plants and animals. However, it is now possible to maintain a healthy diet that does not include animal sources. Human beings have a surprising amount of dietary flexibility, which has contributed to the success of our species. That flexibility has grown remarkably in the modern age, as most people now have access to a very wide and diverse variety of foods and supplements to meet our dietary requirements.
While the “what not to eat” part of a vegetarian diet is straightforward, careful attention needs to be paid to the foods one does consume in order to receive an adequate amount of nutrition. Some vegetarians (pescetarians) elect to eat fish, which makes the diet easier, but it is not ultimately necessary. A lack of meat, or in the case of veganism a lack of animal products altogether, can lead to deficiencies in protein, iron, B12, fatty acids, calcium, and vitamin D if one is not careful. This is much less of a concern for vegetarians who are consuming dairy products and eggs.
Vegans should carefully study the contents of vitamins and nutrients in their foods, their bioavailability, and the daily requirements of a healthy human body. There are many intricacies in nutrition, for example the iron from plant sources is harder for the body to use than the iron from meat sources. Also, there are a number of ways in which what we eat interacts with nutrients that affect how the body stores and uses resources. Many choose to supplement their diets either with pills or with fortified foods, such as iron-enriched orange juice or cereal as a simple way of meeting our daily needs.