DHEA (dehydroepiandrosterone) is most known for being a pro-hormone which in the body gets converted to testosterone and estrogen. It is a long held view that DHEA exerts all its effects via conversion to testosterone and estrogen. However, recent studies show that DHEA also has several interesting non-hormonal actions...
Many studies have highlighted the importance of investigating all major hormones, and correcting deficiencies and imbalances if present.[1-8] Given the known mechanisms of testosterone and GH/IGF-1 in building muscle (and possibly also DHEA in elderly) it is reasonable that age-related low levels of anabolic hormones contribute over time to sarcopenia and frailty.[1, 2, 4, 7, 9, 10] Thus, multiple small effects in aggregate can lead to adverse loss of muscle and disability. In this scenario, if replacement was to occur, it would require lower doses of multiple anabolic hormones. An added benefit to this approach would be fewer side effects from the use of lower hormone doses . In addition, multiple anabolic hormone replacement might also have beneficial additive and/or synergistic effects.[11-13]
A notable study investigated whether supplementation with testosterone and GH together, in physiological doses, results in greater improvements in body composition and muscle performance in older men, compared to testosterone supplementation alone...
The consequences of low testosterone levels (aka low-T) have been primarily investigated in middle-age and older men. However, low-T in young men aged 20-39 years can confer health risks as well...
When it comes to health promotion and longevity, DHEA is a supplement which deserves more attention than it is getting.
DHEA levels (the main circulating form of DHEA in the bloodstream is DHEAS) decrease approximately 80% between ages 25 and 75 year.[1, 2] This large decline in DHEA has led to interest in the possibility that aging related DHEA deficiency may play a role in the deterioration in physiological and metabolic functions with aging, and in the development of chronic diseases.
In support of this, it has been reported that DHEA level is negatively correlated with mortality and risk of developing cardiovascular disease (CVD) (i.e. lower DHEA(S) levels are associated with higher mortality and CVD risk).[3-5] More recently it has been found that a steep decline or extreme variability over time in DHEA(S) levels is associated with higher mortality, more so than baseline DHEA(S) levels.
Aging not only reduces DHEA(S) levels, but also results in an increase in arterial stiffness [7, 8], which is an independent predictor of cardiovascular disease (CVD) risk and mortality.[9-11]
It has been reported that DHEA levels are inversely associated with arterial stiffness (i.e. lower DHEA levels are associated with increased arterial stiffness. [7, 12, 13] Therefore, it is possible that DHEA replacement in older adults could reduce arterial stiffness, and thereby contribute to reduction in CVD and mortality...
Prediabetes is a condition in which blood glucose level is higher than normal but does not reach the level for diabetes diagnosis.[1, 2] Studies have shown that people with prediabetes tend to develop type 2 diabetes within 10 years, and are at increased risk for cardiovascular disease.
Among US adults over 18 years, the prevalence of prediabetes has increased from 29.2% in 1999 to 36.2% in 2010. Considering the entire US population in 2010 (approx. 309 million, data from US Cencus), this corresponds to 112 million US adults, or over one third of the US population.
Data from non-diabetic men have revealed an inverse association between insulin resistance and testosterone levels; i.e. a higher degree of insulin resistance is associated with lower testosterone levels.[4-6] This raises the question whether prediabetes, which is a state of increased insulin resistance, is also associated with low testosterone. However, few studies have investigated testosterone levels in men with prediabetes, and the risk of testosterone deficiency in men with prediabetes has not been reported.
Because the prevalence of prediabetes is affecting such a large number of Americans, and is on the rise, it is important to investigate how this condition might affect testosterone levels. Knowing that can help detect men who are likely to have testosterone deficiency and might be at risk for health complications caused by low-T.
It is well-documented that testosterone levels decline with age in men. After the age of 40 years, total testosterone decreases on average -4 ng/dL ( -0.124 nmol/L) per year  or 1.6% per year , and bioavailable testosterone by -2 to 3% per year.  In older men (over 60 years of age), the average rate of decrement in total testosterone levels has been found to be 110 ng/dL every decade.
However, the relative contributions of changes in health and lifestyle to that decline have not been adequately evaluated. A notable study was set out to investigate this...
Testosterone deficiency, popularly known as "low T", has entered the center stage in both the lay and medical communities. However, how is testosterone deficiency (a.k.a. hypogonadism) diagnosed? What is the testosterone level threshold below which you can say you have low T? What are the references ranges for healthy men?
Testosterone deficiency in men, aka hypogonadism, is associated with increased total and abdominal fat mass, and reduced muscle mass, which negatively impacts body composition.[1, 2] This contributes to development of risk factors like insulin resistance, chronic inflammation, and atherogenic dyslipidemia (a triad of increased blood levels of small, dense LDL particles and triglycerides, and decreased levels of HDL particles), which increase the risk for cardiovascular disease, metabolic syndrome and diabetes.[1, 3-16]