Which nutrient is essential for the transport of oxygen in the blood?

The essential nutrient for the transport of oxygen in the blood is iron. Iron is a crucial component of hemoglobin, the protein found in red blood cells that binds to oxygen in the lungs and carries it to tissues throughout the body. When iron levels are adequate, hemoglobin can effectively perform its function of oxygen transport. A deficiency in iron can lead to reduced hemoglobin production, ultimately resulting in conditions such as anemia, which impairs the body’s ability to transport oxygen efficiently.

Other nutrients listed, such as glucose, calcium, and vitamin D, play important roles in the body, but they are not directly involved in the transport of oxygen. Glucose is primarily an energy source for cells. Calcium is vital for bone health and muscle function, while vitamin D is important for calcium absorption and overall bone health. However, none of these nutrients facilitate the binding and transport of oxygen in the bloodstream like iron does.