Why does thyroid hormone production decrease despite adequate iodine intake when an individual develops resistance to thyroid hormone (RTH)?

💡 Explanation

Thyroid hormone production decreases in RTH due to impaired negative feedback sensitivity at the hypothalamus and pituitary, because thyroid hormones cannot effectively suppress TSH release. Therefore, the thyroid is less stimulated despite sufficient iodine, rather than enhanced iodine uptake compensating for the resistance.

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