Copper

Copper is an essential trace element whose chronic loss, driven by stress and aging, Peat identified as a primary mechanism behind the visible and functional declines of senescence, including loss of elasticity, depigmentation, and decreased respiratory capacity. 1 Its most critical role is as a component of cytochrome c oxidase, the terminal enzyme in the mitochondrial electron transport chain, making it fundamental to oxidative energy production. 2 Peat argued that the body's copper content decreases with age, while iron accumulates, and that this substitution of iron for copper in key enzymes, combined with the loss of copper-dependent antioxidant defenses like cytoplasmic SOD, accelerates free radical damage and the formation of lipofuscin. 1

The relationship between copper and iron is mediated by the copper-binding protein ceruloplasmin, which functions as a ferroxidase, keeping iron in its safe, oxidized state for transport and preventing it from catalyzing damaging reactions. 2 However, Peat cautioned against viewing ceruloplasmin as a simple marker to be aggressively increased, noting that it is an acute phase reactant that rises in response to stress, estrogen, and inflammation. 2 Dinkov elaborated that ceruloplasmin can rise defensively to sequester iron released during necrotic cell death or infection, and that low levels, rather than high, are a sign of low thyroid function, which impairs the body's ability to retain copper. 2 Roddy has written that a deficiency of bioavailable copper, often paradoxically accompanied by toxicity symptoms, can occur when ceruloplasmin is low, rendering copper "biounavailable." 2

Copper status is tightly linked to thyroid function and the broader metabolic state. Peat stated that thyroid hormone is needed to absorb and retain copper, likely by modifying cell structure to pull the mineral in, analogous to how thyroid pulls magnesium into cells. 2 Conversely, any stress that disrupts energy production—including high estrogen, nitric oxide, low thyroid, or darkness—will tend to cause a loss of copper from the respiratory system, allowing iron to fill the vacancy. 9 The stress hormone cortisol is particularly implicated, as it induces the production of metallothionein, a sulfhydryl-rich protein that binds heavy metals. Peat theorized that chronic cortisol exposure leads to an indiscriminate loss of copper alongside toxic metals like cadmium and lead, accounting for the characteristic features of aging. 1

Assessing copper status is challenging, as standard blood tests for iron and copper can be misleading; iron tends to hide in the liver and bone marrow, and serum copper may not reflect tissue bioavailability. 2 Peat suggested that a reliable, non-invasive sign of a copper problem is the loss of pigment in hair or skin, a phenomenon he linked to copper's role in melanin synthesis and illustrated with the case of Carl Pfeiffer, who lost all pigment after years of taking sulfur to deplete copper. 2 Dietary sources of copper include shellfish and liver, though liver also contains significant iron. 9 Peat warned that inorganic copper supplements can degrade nutrients in the stomach by peroxidizing fatty acids, producing a metallic taste, and recommended forms like copper chlorophyllin that do not cause this oxidative damage. 6 Roddy has emphasized that supplemental copper is not recommended, and that improving oxidative function and thyroid activity is the primary means of correcting copper utilization. 2