MCQ IN MEDICINE

Detailed explanation-1: -In humans, a normal thyroid gland produces  85 mcg of T4 and 6.5 mcg of T3 daily (1). Thus, the ratio of T4:T3 that is directly secreted from the thyroid gland is around 13:1.

Detailed explanation-2: -In the pituitary, 80–90% of T4 is converted to T3, while only about 30–50% of T4 in the peripheral tissue is converted to active T3.

Detailed explanation-3: -TPO then produces T4 and T3 by transporting iodine to our thyroid. Our thyroid gland then produces T4 and T3. The majority of the hormone production in the thyroid is inactive T4. Our bodies cannot utilize T4, so it has to convert T4 into T3 to become useful to our system.

Detailed explanation-4: -Desiccated thyroid has roughly a 4:1 ratio of thyroxine (T4) to triiodothyronine (T3). In humans, the ratio is 11:1. A combination of various ratios of T4 and T3 might not provide benefits over T4 alone. Some controlled trials have shown inconsistent benefits of various ratios of T4 and T3.