There are different types of vegetarians such as lacto-vegetarians who eat dairy but not eggs, ovo-vegetarians who eat eggs but not dairy, and pescetarians who eat fish and dairy but not poultry or meat. Vegans do not eat meat, fish, dairy, eggs, or honey. People become vegetarian or vegan for reasons like religion, ethics, health, or the environment. Vegetarians and vegans can get adequate nutrients but may need to pay special attention to getting enough iron, selenium, vitamin B12, omega-3 fatty acids, protein, and calcium.