Which mineral is vital for oxygen transport in the blood?

Iron is the mineral that plays a crucial role in oxygen transport within the blood. It is a key 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. Each hemoglobin molecule can bind up to four oxygen molecules, and the presence of iron is what allows this binding to occur effectively. When iron levels are insufficient, hemoglobin production can be impaired, leading to reduced oxygen delivery to cells, which results in fatigue and other health issues.

In contrast, calcium is primarily involved in bone health and muscle function, sodium plays a role in fluid balance and nerve transmission, and potassium is important for maintaining proper cell function and regulating heartbeat. While these minerals are essential for various bodily functions, they do not participate directly in the transport of oxygen within the bloodstream like iron does. Thus, iron is essential for efficient oxygen transport, making it the correct choice.