Which nutrient is primarily involved in oxygen transport in the blood?

The primary nutrient involved in oxygen transport 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 is present in hemoglobin, it allows for the efficient transport of oxygen, which is essential for cellular respiration and energy production in all living cells.

While carbohydrates provide energy, proteins have a variety of roles in the body, including structural support and enzyme function, and calcium is vital for bone health and muscle function, they do not play a direct role in the transport of oxygen in the blood. Iron specifically is the element that enables hemoglobin to effectively carry oxygen, highlighting its critical role in this process.