Copper is an essential trace mineral, playing a fundamental role in various biological processes. It circulates in the bloodstream primarily bound to proteins. The body carefully regulates its levels to ensure proper functioning and prevent harm from either too little or too much copper. This regulation involves complex mechanisms of absorption, transport, and excretion.
Copper’s Essential Functions
Copper acts as a cofactor for numerous enzymes, as a necessary component for their functions. These cuproenzymes are involved in energy production within cells, particularly in the mitochondria, where they play a part in converting oxygen to water during cellular respiration. Copper is also linked to iron metabolism, helping the body properly utilize iron. It aids in mobilizing iron from storage and enabling its transport, which is important for red blood cell formation.
Copper supports the immune system by contributing to the production and maturation of white blood cells, such as neutrophils, to fight infections. It is involved in nerve function and brain development, contributing to the synthesis of neurotransmitters and the formation of myelin sheaths that insulate nerve fibers. Additionally, copper is essential for the formation of connective tissues like collagen and elastin. It acts as a cofactor for lysyl oxidase, an enzyme that forms cross-links in these proteins, providing strength and elasticity to tissues such as skin, bones, and blood vessels.
Maintaining Copper Balance
The body maintains tight control over copper levels. Copper is absorbed from dietary sources primarily in the small intestine. Once absorbed, it enters the bloodstream and is transported to the liver via the portal circulation. In the blood, copper is mainly carried by proteins like ceruloplasmin. Ceruloplasmin, synthesized in the liver, transports most of the copper in plasma.
The liver plays a central role in copper homeostasis, either incorporating it into proteins like ceruloplasmin for distribution to other tissues or facilitating its removal from the body. Excess copper is primarily eliminated through bile, which is then excreted in feces. This balance of absorption, transport, and excretion ensures that copper levels remain within a healthy range, preventing both deficiency and toxicity.
Consequences of Imbalance
When copper levels are outside their optimal range, either too low or too high, serious health issues can arise. Copper deficiency can occur due to malabsorption issues, prolonged nutritional deficiencies, or genetic conditions. One genetic disorder, Menkes disease, impairs the body’s ability to transport copper from the intestines into the bloodstream, leading to severe copper deficiency despite sufficient intake. Symptoms of copper deficiency can include anemia, neurological problems such as poor coordination or muscle weakness, impaired immune function and increased susceptibility to infections, and issues with connective tissue and bone integrity.
Conversely, copper toxicity can result from excessive dietary intake, environmental exposure, or genetic predispositions. Wilson disease is a rare inherited condition where the body cannot properly excrete excess copper, leading to its accumulation in various organs. This buildup can cause liver damage, neurological symptoms like tremors and speech difficulties, and psychiatric changes. While acute copper poisoning from ingesting large amounts is rare, chronic accumulation from genetic conditions or environmental factors can result in severe organ damage and can be life-threatening if untreated.