Iron Facts: What It Is and Why We Need It
Iron is a key element in the metabolism of almost all living organisms. In humans, iron is an essential component of hundreds of proteins and enzymes. As the National Institutes of Health state:
Iron is an essential component of hemoglobin, an erythrocyte protein that transfers oxygen from the lungs to the tissues. As a component of myoglobin, a protein that provides oxygen to muscles, iron supports metabolism. Iron is also necessary for growth, development, normal cellular functioning, and synthesis of some hormones and connective tissue
Most of the symptoms of iron deficiency are a result of the associated anemia, and may include fatigue, rapid heart rate, palpitations, and rapid breathing on exertion. Iron deficiency impairs athletic performance and physical work capacity in several ways. In iron deficiency anemia, the reduced hemoglobin content of red blood cells results in decreased oxygen delivery to active tissues
During pregnancy, mothers need to increase their iron intake because it’s needed for the developing fetus and placenta, as well as blood volume expansion.
Because iron from plant sources is less efficiently absorbed than that from animal sources, the U.S. Food and Nutrition Board has estimated that the bioavailability of iron from a vegetarian diet is only 10%, while it is 18% from a mixed diet. Therefore vegetarians need to increase their intake of iron. However, that doesn’t mean relying solely on supplements. We have a great article on how to get iron from plant sources. We’ve also created a helpful infographic below, which lays out some of the top iron sources. You’ll find it’s mostly vegetarian.
Below that, we have a second graphic listing the recommended daily allowances for iron in a person’s diet, so you know how much you should be getting.