Which statement aligns best with how many people are unaware of their thyroid issues?
About 60% are unaware.
Which stats most accurately reflect the prevalence worldwide of thyroid disorders?
Approximately 10% of the global population.
Graves’ disease comprises 60–80% of hyperthyroidism, yet about half relapse within 1 year after anti-thyroid meds. This suggests what major failing?
Treating symptoms not root cause—autoimmunity isn’t addressed; over-reliance on medication alone.
True or False: Women have about three times higher incidence of thyroid cancer than men, with a 283% rise from 1990 to 2013.
ture!
A male 65-year-old has a ~1 cm nodule. What percentage of the population has a thyroid nodule by age 60?
About 50%.
Why is TSH alone insufficient?
It misses FT4/FT3 status; doesn’t detect autoimmunity; pituitary D2 can mask tissue hypothyroid; wide ranges delay care; misses conversion/clearance issues.
Which statement about iodine and hypothyroidism is correct?
In Hashimoto’s (≈90% of hypothyroid), iodine can worsen disease;
goitrogens may help by lowering iodine uptake.
A coach prescribes bioidentical T3 without checking deiodinase or hormone fluctuations. Which error is this?
Premature T3 replacement without assessing conversion/regulation; ignoring potential fluctuating hypo/hyper.
Thyroid hormones elicit which metabolic activities?
Increase BMR/thermogenesis;
regulate lipid and glucose metabolism;
increase cardiac output/HR; support GI motility;
influence mood/cognition;
support growth/bone maturation.
True or False: T4 is a pro-hormone with ~1-week half-life; T3 is more active with a shorter half-life. A:
true
An elevation in parathyroid hormone might be suspected if?
Low vitamin D;
low calcium or malabsorption; CKD/secondary hyperparathyroidism;
bone loss.
TRH has which effects beyond initiating TSH release? A:
Stimulates prolactin; CNS effects including arousal/thermoregulation; impacts autonomic tone.
A 28-year-old TSH 1.9 mIU/L at 4pm, no T4/T3. Why might this be inaccurate for subclinical hypothyroidism? A:
Afternoon draw and fed state can lower TSH; missing FT4/FT3 prevents identification.
A 35-year-old male has minimal TSH, normal FT4/FT3, no antibodies, no meds. Best explanation?
A: Physiologic low pituitary set point/central adaptation with euthyroid hormones.
True or False: TSH 1.72 vs 1.01 is associated with higher miscarriage risk. A:
True.
In terms of thyroid hormone output, what percentage is typically T4?
A: About 80–90% (roughly 90% T4, 10% T3).
A 61-year-old with “subclinical low T3,” normal TSH/T4, chronic inflammation. Where to suspect issues?
A: Peripheral conversion—deiodinase dysfunction (reduced D1, increased rT3 pathway).
How much more metabolically potent is T3 compared to T4?
A: Approximately 3–4 times.
giver overview of thyroglobulin
Follicular storage protein for thyroid hormones; source of T3/T4 when proteolyzed;
TgAb indicates autoimmunity and can interfere with Tg assays;
Tg can rise with tissue destruction or cancer (context-dependent
Which two major anti-thyroid antibodies are clinically tested most often
A: Anti–thyroid peroxidase (TPO) and anti–thyroglobulin (TgAb).
A 46-year-old female has elevated TPO but no hypothyroid signs. Why?
A: Euthyroid autoimmunity phase; antibodies can precede dysfunction for years; influenced by iodine/postpartum/immune shifts.
Why might a female on the oral contraceptive pill have lowered thyroid function?
A: Estrogen increases TBG lowering free T4/T3;
altered hepatic binding/clearance;
potential micronutrient effects on conversion.
Which deiodinase is critical for T4→T3 in liver/kidneys and can contribute to rT3 dynamics under stress?
A: Type 1 deiodinase (D1): main T4→T3 in liver/kidney; under stress D1 drops while D3 inactivates T4→rT3.
Type 3 deiodinase does what?
A: Inactivates thyroid hormones: T4→rT3 and T3→T2.
