Final answer:
Increased intake of iodine can potentially worsen hyperthyroidism as it provides more substrate for an already overactive thyroid gland, potentially increasing the production of thyroid hormones.
Step-by-step explanation:
Seafood and milk are known for their high levels of iodine, which is essential for the production of thyroid hormones T3 and T4. Hyperthyroidism is a condition characterized by an overactive thyroid gland, which produces excessive amounts of these hormones. Since iodine is required for the synthesis of T3 and T4, increased intake of iodine can potentially worsen hyperthyroidism by providing more substrate for the overactive thyroid to produce these hormones. Therefore, for someone with hyperthyroidism, it is recommended to moderate dietary iodine intake to avoid exacerbating the condition.