What is the function of iodine and its typical daily intake?

• A. Energy metabolism; 60 mcg daily
• B. Regulated growth and development; 150 mcg daily
• C. Bone mineralization; 500 mcg daily
• D. Protein synthesis; 1000 mcg daily

Answer: (B)

Iodine is essential for the production of thyroid hormones (T3 and T4), which regulate growth and development, including brain development in the fetus and during early life, and also help control metabolic rate. Adequate iodine intake ensures normal thyroid hormone synthesis, supporting proper growth and development. The typical daily intake for adults is about 150 micrograms per day, commonly met through iodized salt and foods like seafood and dairy; pregnancy increases needs, but that doesn’t change the basic adult recommendation. The other proposed daily amounts don’t align with standard guidelines for supporting thyroid hormone production, and the functions listed (bone mineralization or protein synthesis) aren’t the primary roles of iodine.