ManageFirst Nutrition Practice Test 2026 - Free Nutrition Practice Questions and Study Guide

Iron is crucial for oxygen transport in the body primarily because it is a key component of hemoglobin, the protein in red blood cells that binds to oxygen. When red blood cells circulate through the lungs, hemoglobin captures oxygen from inhaled air. When these cells travel to tissues throughout the body, hemoglobin releases the oxygen, making it available for cellular respiration and energy production.

Iron’s role in oxygen transport is vital for maintaining adequate energy levels and ensuring that all cells receive the oxygen they need to function properly. Without sufficient iron, the body can become deficient in red blood cells or hemoglobin, leading to conditions such as anemia, which can significantly impair oxygen delivery and overall health.

The other minerals listed do play important roles in various bodily functions but are not directly involved in the transport of oxygen. For instance, calcium is essential for bone health and muscle contraction, potassium is important for maintaining fluid balance and nerve function, and zinc plays critical roles in immune function and metabolism.