The higher the TSH level, the lower the level of thyroid hormone production.

WSJ: U.S. Track's Unconventional Physician

Suspected human carcinogen, interferes with normal reproductive system development and thyroid hormone levels.

FORBES: Connect

Diagnosis of low thyroid hormone are made via blood samples that measure levels of another hormone called TSH that induces thyroid production.

WSJ: U.S. Track's Unconventional Physician

Anthony Famiglietti, a 2004 and 2008 Olympian in the steeplechase, stopped taking synthetic thyroid hormone two months after being given a prescription for it in 2011.

WSJ: U.S. Track's Unconventional Physician

Flame retardants, which are found in textiles, computer casings, sofa foam and other household items, have been shown to interfere with thyroid hormone, essential for healthy brain development.

FORBES: Hidden Household Toxins

Such a physician might be able to guide the parents of colicky babies through a difficult time that is (mercifully) usually transient, and could also help patients requiring hormone replacement therapy (whether for low thyroid hormone levels or low testosterone levels) decide what replacement dose makes sense, and reach a conclusion that would be informed by numeric criteria but not exclusively defined by it.

FORBES: Are doctors over-responsive to patients -- or not attentive enough? (Answer: yes.)

This means the "under-active" thyroid gland in her neck does not produce enough of the thyroxine hormone.

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The other hormone that gets a bad rap when it comes to causing anxiety is from your thyroid gland.

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