Iron is an essential nutrient found in both tofu and tempeh. It is a mineral that helps to transport oxygen throughout the body, and is important for energy production and metabolism. Tofu and tempeh are both plant-based sources of IRON, making them a great choice for vegetarians and vegans. IRON from plant sources is not as easily absorbed by the body as IRON from animal sources, so it is important to combine these foods with other sources of vitamin C to increase absorption.