If a patient with a history of iodine deficiency undergoes gastric bypass surgery, which consequence on thyroid hormone regulation is most likely?

💡 Explanation

Gastric bypass can impair nutrient absorption, including selenium, required for deiodinase enzymes that convert T4 to T3. This leads to reduced peripheral T4 to T3 conversion because less selenium impairs deiodinase activity; therefore, T3 levels decrease, rather than affecting TSH secretion directly.

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