Spinach is relatively rich in nitrogenous substances, in hydrocarbons, and in iron sesqui-oxide, which last amounts to 3.3 per cent of the total ash. It is thus more nourishing than other green vegetables. It is a valuable part of the diet in anemia, not only on account of its iron, but also for its chlorophyll. Chlorophyll is known to have a chemical formula remarkably similar to that of hemoglobin, and it is stated that the ingestion of chlorophyll will raise the hemoglobin of the blood without increasing the formed elements.Spinach comes from a central and southwestern Asian gene center where it may have originated from Spinacia tetranda, which is still gathered as a wild edible green in Anatolia. Spinach was unknown to the ancient Mediterranean world.Three basic variants of modern spinach are Savoy which has dark green, crinkly and curly leaves; Semi-savoy, a hybrid variety which has slightly crinkled leaves and is much easier to clean than standard Savoy; and Flat- or smooth-leaf spinach which is, even more, easier to clean because of its smooth leaves.