Men - Why Test These Hormones?
- Testosterone
- SHBG - Sex Hormone Binding Globulin
- Free Testosterone Index
- PSA - Prostate Specific Antigen
- IGF-1 - an index of Human Growth Hormone (Profile II)
Testosterone is important for:
- energy production (ATP)
- preventing mental and physical fatigue
- maintaining sex drive
- building and maintaining healthy skin, bone and muscles
Testosterone deficiency can cause:
- loss of bone density (osteoporosis)
- night sweats
- mental burnout
- insulin resistance
- decreased muscle mass
- erectile dysfunction
- low physical stamina
- low sex drive
- depression
- cardiovascular disease
- immune dysfunction
SHBG is important because:
- It is used as a relative index of your overall exposure to all forms of estrogens: those produced by your body (endogenous) and those consumed (phytoestrogens, xenoestrogens)
- It is an indirect index of estrogen interaction with the liver.
- It is the protein that binds tightly to total testosterone in the circulation and limits the amount of testosterone bioavailable to tissues.
- High levels indicate excess exposure to estrogens and lower availability of testosterone to tissues.
SHBG outside the expected range indicates:
- An imbalance between testosterone to estrogen.
- High = overall estrogen burden
- Low = low estrogen, more bioavailable testosterone
- Andropause onset and/or rapid aging in men (see above).
- Increased risk of prostate disease.
PSA is important because:
- It is a protein produced by the prostate gland that we can measure.
- It is an important indicator of prostatic enlargement or increased risk of cancer.
- PSA needs to be within the expected range for two good reasons:
- High PSA levels are a warning sign of prostate health risks.
- Normal PSA evaluation is prerequisite to initiating testosterone therapy.
IGF-1 is Important because:
- It is a reliable indicator of human growth hormone.
- Low IGF-1 levels indicate Adult Growth Hormone Deficiency associated with rapid aging, decreased muscle and bone mass, slowing cognition, low libido and poor quality of life.
References
Gambineri A., and Pasquali R. Testosterone therapy in men: Clinical and pharmacological perspectives. J Endocrinol. Invest. 23: 196-214, 2000.
Bjorntorp P. The regulation of adipose tissue distribution in humans. International Journal of Obesity 20:291-302, 1996.
Marin P. Effects of androgens in men with the metabolic syndrome. The Aging Male 1 (1998) 129-136.