The thyroid stimulating hormone (TSH) is produced and secreted by the pituitary gland and stimulates the thyroid to produce T3 and T4. When TSH is elevated, low thyroid function may be indicated. If TSH is low it is indicative of high thyroid function. A study found that TSH was suppressed in all subjects after food, so fasting may be suggested although it is not reqired by Quest. Free T4 and Free T4 values did not change significantly after eating.

THIS IS THE MOST AFFORDABLE TESTOSTERONE TEST IN THE U.S. The most accurate way to measure total testosterone is with liquid chromatography/mass spectrometry. This panel also shows free testosterone percent by equilibrium dialysis and free testosterone calculated from percent free T. This test is more accurate for low and high testosterone blood levels (for men who expect high testosterone blood levels over 1,500 ng/dL, women, and children who usually have low T levels). It has no interferences with supplements or anabolics. Note: Results may take 5-7 business days. For a faster turnaround, choose this test instead: Testosterone, Free, Bioavailable and Total (With Lower & Upper Limit) plus SHBG

A single fasting growth hormone (GH) level is of limited value. The secretion of GH is episodic and pulsatile. GH has a half-life of 20 to 25 minutes. Testing for growth hormone deficiency or excess is best done as part of a dynamic test involving specific stimuli (see the online Endocrine Appendices: Growth Hormone Stimulation and Growth Hormone Suppression). Insulin-like growth factor-1 can also be useful in assessing growth hormone status.

This test is not the sensitive estradiol test but the regular one. It is not recommended for men (it is adequate for pre-menapausal women).  The results from this test are usually available 2 business days faster than the sensitive estradiol test.

Includes liver and kidney function, glucose and electrolytes

Pregnenolone is known as the mother hormone. All other steroids including testosterone and estrogen are derived from this important hormone. For this reason, optimal blood levels of pregnenolone are critical for a healthy hormone balance.  This test uses liquid chromatography/mass spectrometry, the most accurate assay for hormones.

Insulin-like Growth Factor 1, also known as IGF-1, is used as a biomarker for blood levels of human growth hormone. It is a hormone produced by the liver and other tissues which affects growth-promoting activities and glucose metabolism. The blood level of IGF-1 appears to fluctuate over 24 hours and is found to be related to growth hormone secretion.

SHBG (sex hormone binding globulin) binds to testosterone and estradiol. High SHBG may decrease free testosterone and free estradiol.

 A prolactin blood test is used by doctors to evaluate sexual dysfunction or very low testosterone blood levels of unknown causes in both men and women.

Cortisol (hydrocortisone) is the most prominent glucocorticosteroid, and it is essential for the maintenance of several body functions. The most important physiological effects of cortisol are that it raises blood sugar levels (enhances gluconeogenesis, or breaks down glucose) and lowers inflammation and the immune system.

This panel includes comprehensive testing of the thyroid stimulating hormone (TSH) in addition to free thyroxine (T4) and free triiodothyronine (T3).

The electrolyte panel includes: Carbon dioxide, chloride, potassium, and sodium