Cascade of homeostatic failure.
Iron accumulation causes brain degeneration, hart dicease, possibly diabetes and some forms of cancer. The body likely evolved in times where iron was scarce, so it has no way of excreting excess iron.
Copper deficiency. Causes diminished cognition, especially tunnel vision and distorted perception. Also necessary in the immune system and two less important superoxide dismutase enzymes. The amounts used in animal feeds suggest that the belief of its toxicity is likely false.
Manganese. Required in the most important SOD present in mitochondria.
Molybdenum. Several detoxification enzymes.
Magnesium. Involved in processes regualating other minerals, its deficiency makes worse all of the above. Causes caclifications, bone loss, brain fog/depression, allergies, atherosclerosis and possibly others.
Calcium. Depletes magnesium, makes all the things above worse.