Why does thyroxine (T4) conversion to triiodothyronine (T3) decrease during prolonged starvation?

💡 Explanation

Decreased T4 to T3 conversion occurs in starvation because the body attempts to conserve energy by reducing the metabolically active T3; this involves decreased activity of deiodinase enzymes. Therefore, energy conservation is the primary driver, rather than increased glycogen or TRH secretion.

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