The element essential for the formation of blood cells is iron. Iron plays a crucial role in the production of hemoglobin, the protein in red blood cells that carries oxygen from the lungs to the rest of the body. It is vital for overall health, and its deficiency can lead to anemia, characterized by fatigue and weakness due to reduced oxygen transport. Iron is found in various foods, including red meat, beans, lentils, spinach, and fortified cereals. Maintaining adequate iron levels is essential for ensuring that the body functions optimally and supports physical health and energy levels.