What role does Ferritin play in blood sugar?

Ferritin is the primary iron storage protein. Elevated ferritin levels may indicate iron overload, which can promote oxidative stress and insulin resistance, both linked to higher blood sugar. Observational studies have associated high ferritin with increased risk of type 2 diabetes, but ferritin also rises as an acute-phase reactant during inflammation, confounding the relationship. Conversely, low ferritin (iron deficiency) can impair glucose metabolism because iron is essential for insulin synthesis and signaling. The evidence is moderate: mostly epidemiological, with limited interventional data. Therefore, ferritin alone is not a reliable predictor of blood sugar dysregulation. It should be interpreted alongside other markers like HbA1c, fasting glucose, and inflammatory markers. A direct causal role is not established.