Free testosterone (T) is transported into the cytoplasm of target tissue cells, where it can bind to the androgen receptor, or can be reduced to 5α-dihydrotestosterone (DHT) by the cytoplasmic enzyme 5α-reductase. DHT binds to the same androgen receptor even more strongly than testosterone, so that its androgenic potency is about 5 times that of T. The T-receptor or DHT-receptor complex undergoes a structural change that allows it to move into the cell nucleus and bind directly to specific nucleotide sequences of the chromosomal DNA. The areas of binding are called hormone response elements (HREs), and influence transcriptional activity of certain genes, producing the androgen effects.
Nearly 1 out of every 4 men over age 50 experience the pain of losing the ability to perform sexually as a result of erectile dysfunction (ED). Common causes of ED are atherosclerosis, diabetes, prescription drug use (namely high blood pressure, depression, and allergy drugs), and—you guessed it—low testosterone. Supplements that may help include the following:
However, testosterone is only one of many factors that aid in adequate erections. Research is inconclusive regarding the role of testosterone replacement in the treatment of erectile dysfunction. In a review of studies that looked at the benefit of testosterone in men with erection difficulties, showed no improvement with testosterone treatment. Many times, other health problems play a role in erectile difficulties. These can include:
Dr. Anthony’s Notes: I use Maca often in cycles throughout the year. I typically buy the raw Maca powder, which has a VERY “dirt-like” earthy taste. Beware if you are a bit squeamish on tastes! How To Take Maca: 1500-3000mg of Maca powder is a typical dosage take daily alongside food. From personal experience, I've found that it’s best to buy the Maca powder as a standalone supplement and throw it into a blended protein shake to mask the taste.
On review of the patient’s history, he was found to have undergone laboratory tests before starting to use the aforementioned testosterone booster product. All blood parameters (testosterone hormone and full chemical profile) before product intake were in the normal range. A physical examination that included blood pressure and pulse assessments showed nothing out of the ordinary, and the man appeared to be in good condition before product consumption. After that medical checkup, the athlete began to consume the product for 42 continuous days divided into 2 cycles (each cycle comprised 24 days). The daily dose was a single pack of Universal Nutrition Animal Stak (ingredients are listed in Table 1), following the exact direction of the manufacturing company hoping to get the best results.
Longitudinal studies in male aging studies have shown that serum testosterone levels decline with age (Harman et al 2001; Feldman et al 2002). Total testosterone levels fall at an average of 1.6% per year whilst free and bioavailable levels fall by 2%–3% per year. The reduction in free and bioavailable testosterone levels is larger because aging is also associated with increases in SHBG levels (Feldman et al 2002). Cross-sectional data supports these trends but has usually shown smaller reductions in testosterone levels with aging (Feldman et al 2002). This is likely to reflect strict entry criteria to cross-sectional studies so that young healthy men are compared to older healthy men. During the course of longitudinal studies some men may develop pathologies which accentuate decreases in testosterone levels.
"Some say it's just a part of aging, but that's a misconception," says Jason Hedges, MD, PhD, a urologist at Oregon Health and Science University in Portland. A gradual decline in testosterone can't explain a near-total lack of interest in sex, for example. And for Hedges' patients who are in their 20s, 30s, and early 40s and having erectile problems, other health problems may be a bigger issue than aging.