IL1B and acute respiratory distress syndrome: Studies have shown that the T3 concentration affects macrophage activity.[18] Hyperthyroidism reduces inflammation, whereas hypothyroidism promotes phagocytosis and increases IL‐1β expression in macrophages.[19] The effects of TH and thyromimetics on macrophage polarization in ALI/ARDS are still unclear despite some evidence suggesting that T3 can reverse proinflammatory cytokine levels in hypothyroid or type 2 deiodinase knockout mice.[15]