What are signs of iodine deficiency and dietary sources?

• A. Iodine deficiency has no effect on thyroid function.
• B. Goiter and hypothyroidism symptoms; dietary sources include iodized salt, seafood, and dairy.
• C. Iodine is not found in dairy products.
• D. Iodine supplements are always safe and recommended for all adults.

Answer: (B)

Iodine is essential for thyroid hormone synthesis, so deficiency directly affects thyroid function. Without enough iodine, the thyroid can’t make enough T4 and T3, prompting the pituitary to release more TSH. That extra stimulation causes the thyroid to enlarge, producing goiter, and leads to symptoms of hypothyroidism such as fatigue, cold intolerance, weight gain, constipation, and dry skin. Getting sufficient iodine through the diet helps prevent these issues. Common dietary sources are iodized salt, seafood, and dairy products, with other good options including eggs and seaweed. It’s important to remember that iodine supplementation isn’t universally safe or recommended for everyone; taking too much iodine can disrupt thyroid function, so supplements should be used under medical guidance.