Vegetarianism is a diet that is comprised of mainly plant foods and thus lacks animal proteins which is then replaced with vegetable protein sources (ie.soy). A vegetarian diet does not include fish, a major source of omega-3 fatty acids, though some plant-based sources of it exist such as soy, hempseed, pumpkin seeds. canola oil and especially, walnuts and flaxseeds (click to see how to eat them).
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Lacto-vegetarian: those who do not eat meat or eggs but do consume dairy products.
Lacto-ovo-vegetarian: those who do not eat meat but do consume dairy products and eggs.
Ovo-vegetarian: those who do not eat meat or dairy but do eat eggs.
Veganism: those who avoid eating any animal products including eggs, milk, cheese and sometimes honey, are known specifically as dietary vegans. Most also avoid using animal products such as leather and some cosmetics, and are called vegans.
Raw foodist: a raw food diet involves food (usually vegan) that is not heated above 116F; it may be warmed slightly or raw, but never cooked. Raw foodists argue that cooking destroys enzmyes and/or portions of each nutrient