Iron at the Crossroads of Thyroid Function and Detoxification in Women: Clinical Implications for Diagnosis and...

Iron deficiency is one of the most prevalent micronutrient disorders worldwide and disproportionately affects women across the lifespan. While its hematologic consequences are well recognized, the broader endocrine and metabolic implications of iron status remain underappreciated in routine clinical care. Iron is a critical cofactor in thyroid hormone synthesis and metabolism and plays a central role in hepatic detoxification pathways, mitochondrial energetics, and hormone regulation. Disruptions in iron homeostasis may therefore contribute to thyroid dysfunction, impaired detoxification capacity, and symptom patterns that overlap with hypothyroidism, particularly in women with increased physiologic demands such as menstruation, pregnancy, and perimenopause. This narrative review examines the interconnected roles of iron in thyroid physiology and detoxification systems, with a focus on clinical implications for women's health. We discuss mechanisms linking iron deficiency to altered thyroid hormone production, hepatic cytochrome P450 activity, estrogen metabolism, and mitochondrial function. Diagnostic challenges, including the interpretation of ferritin and iron indices in thyroid patients, are reviewed alongside evidence-informed therapeutic strategies. A systems-based clinical framework is proposed to guide screening, evaluation, and management of iron deficiency in women with thyroid disorders. Recognizing iron as a central regulator at the intersection of thyroid and detox pathways may improve patient outcomes and inform more comprehensive approaches to endocrine care.