Heme Synthesis Disruption Most discussions around fatigue in mold or heavy metal exposure focus on mitochondrial dysfunction . While that is valid, it often overlooks a rarely discussed upstream process: heme synthesis . Heme is not just part of hemoglobin. It is required for: Oxygen transport (hemoglobin, myoglobin) Mitochondrial electron transport chain (cytochromes) Liver detox enzymes (cytochrome P450 system) Catalase (hydrogen peroxide breakdown) Without adequate hem