Vitamin B12 is needed by everybody, but it’s a real problem for those following a vegan or vegetarian diet, as there isn’t a source of it in those diets. Vitamin B12 is vital for healthy blood cells, supporting the nervous and digestive systems, and for energy. It’s what the body needs to convert carbohydrate into glucose, and therefore the energy for our bodies to use. Being deficient in Vitamin B12 can cause anemia, nerve damage, heart diseases, problems conceiving or during pregnancy, and many other ailments. The common advice for vegans and vegetarians is get a Vitamin B12 supplement.