Too many diagrams focus on the "HPT axis," in which the Hypothalamus, the Pituitary, and Thyroid gland are the biggest icons. Take for example this diagram from Ortiga-Carvalho's chapter in a physiology textbook. The huge, super-ballsy pituitary. Seriously? In diagrams like these (this is not the only such pictorial), the truly pea-sized TSH-secreting pituitary gets … Continue reading Visual bias: The pituitary gland in HPT axis diagrams
In health, what happens when your tissues don't convert enough T4 into T3 hormone? Your healthy thyroid secretes more T3. The healthy thyroid gland's synthesis of T3 de novo (from raw materials of iodine and tyrosine) under the stimulation of a healthy TSH can maintain your circulating T3 supply. This prevent tissues from becoming hypothyroid … Continue reading Thyroid T3 secretion compensates for peripheral T4-T3 conversion
Why are some people extremely hypothyroid while their TSH is above reference range, while others have no symptoms and are completely healthy? How important is the Free T3 test when diagnosing true "euthyroid" status within the TSH reference range? Is it true that a normal TSH alone, or a normal TSH and normal FT4 test … Continue reading Relational Stability, part 3: Shifting TSH-T4-T3 relationships
In a series of posts, I'm sharing my plainer-English paraphrase of a very important article in thyroid science. My hope is that the public, doctors, and educated thyroid patients can better understand and appreciate its insights. This article by Dr. Rudolf Hoermann and colleagues Midgley, Larisch, and Dietrich explains the complex interrelationships between TSH, T4 … Continue reading Relational stability among thyroid hormones and TSH, part 1
This comprehensive educational post collects the basics of thyroid hormone, transport and conversion. T3 action on nuclear receptors Every organ and tissue in your body must maintain a healthy level of T3 hormone activity to function properly. Bloodstream T3 supply and local T3 action powerfully influences how every organ operates, from our liver to our … Continue reading The basics of thyroid hormone action, transport and conversion
