Which micronutrient deficiency is the single most common cause of preventable intellectual disability (mental retardation) worldwide?
- A Iodine ✓
- B Iron
- C Folate
- D Zinc
Correct answer: A. Iodine
Explanation
Iodine deficiency during fetal life and infancy impairs thyroid hormone synthesis, causing cretinism and a spectrum of cognitive deficits collectively called iodine deficiency disorders. It remains the commonest preventable cause of intellectual disability globally. Iron deficiency anaemia also affects cognition, which makes it the tempting distractor, but iron deficiency is not classically listed as the leading cause of preventable mental retardation; that position belongs to iodine.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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