Iron homeostasis and health: understanding its role beyond blood health - a narrative review.

Iron is an essential trace element that plays a critical role in numerous physiological processes, including oxygen transport, cellular metabolism, immune function, and organ health. While its most well-known function is in hemoglobin synthesis for blood health, iron's regulatory mechanisms extend far beyond the bloodstream. This review examines the broader implications of iron homeostasis, focusing on its impact on cellular functions, immune responses, and the health of organs such as the liver, heart, and brain. Disruptions in iron regulation, including both deficiency and overload, can lead to various disorders, including anemia, iron overload diseases, and chronic inflammation. Iron homeostasis is maintained by a complex balance of absorption, storage, and recycling, primarily regulated by hepcidin, a liver-derived hormone. Inadequate iron levels can impair mitochondrial function, DNA synthesis, and immune cell activation, leading to fatigue, anemia, and a weakened immune system. Conversely, excess iron can promote oxidative stress, contributing to tissue damage and conditions like hemochromatosis, cardiomyopathy, and neurodegenerative diseases. The liver, kidneys, heart, and brain are particularly sensitive to changes in iron balance, which can exacerbate or precipitate various health complications.