Research Supporting Testosterone Replacement
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1. Bringing testosterone from low normal to high normal lowers the risk for heart disease by 60%.
2. Low testosterone linked to long-term risk of death in relatively healthy adult men. This study is another major report linking testosterone deficiency in relatively healthy men with increased death
from all causes over time.
3. Two-year study of the effects of low dose testosterone on men’s libido. 82% of men noticed improvement compared to less than 10% in the control group.
Clinical Endocrinogy and Metabolism 1997.
4. In one of the largest studies of its kind, this study shows a decline in American men’s testosterone levels during the last 20 years. The decrease is not related to normal aging or to health and lifestyle factors known to influence testosterone levels. Testosterone concentrations dropped about 1.2% per year from 1987 to 2004, or about 17% overall. The downward trend was seen in both individuals and the entire population over time.
5. Dihydrotestoerone reduces prostate size.
6. Testosterone Improves Sexual Function, Mood, Muscle Strength and Body Composition Parameters in Hypogonadal Men. Subjects did not exercise, yet their lean body mass and fat mass improved. Improvement was correlated with serum level of Testosterone obtained. Study showed that these benefits were not, however, obtained with testosterone patches (which are too weak for most patients).
7. Testosterone supplementation increases working memory in men.
8. Testosterone Prevents Mental Decline in Aging Males. This study provides a longitudinal assessment of serum free testosterone concentration which was able to predict memory performance and cognitive status in elderly men.
9. Testosterone replacement reduces the risk of Alzheimer’s Disease by preventing the production of beta amyloid precursor proteins.
10. Testosterone levels correlate with improved cognitive function. Testosterone replacement provides the levels of testosterone needed for this improved function.
J Clin Endocrinol Metab 1999 Oct;84(10):3681-5.
11. Testosterone replacement is more effective than antidepressants for depression.
Androl 1992 Jul-Aug;13(4):297-304
12. Low testosterone levels is associated with fatigue. Using testosterone replacement increases one’s sense of well being. Many patients were also able to stop using antidepressants after testosterone replacement.
13. The lower one’s active testosterone level, the higher the risk for heart attack.
14. Men with heart disease have significantly lower total testosterone, free testosterone and bioavailable testosterone. Men with coronary artery disease also have lower levels of androgens than men with normal coronary angiograms. “Short-term administration of testosterone induced beneficial effect on exercise induced blood flow to the hearts of men with coronary artery disease.” In addition to dialitating coronary arteries, testosterone with exercise was shown to improve short term depression.
This effect may be related to a direct coronary-relaxing effect.”
15. This study shows the relationship between testosterone and heart disease. Low testosterone increases the risk of heart disease, while more optimal levels decrease the risk of heart disease.
16. This reports a study of dihydrotestosterone and testosterone levels in men screened for prostate cancer. Low testosterone levels increased the risk of prostate cancer. Testosterone replacement is expected to reduce the risk of prostate cancer.
17. DHT is lower in prostate cancer patients and in patients with more advanced tumors. PSA and DHT have an inverse relationship (that is to say the higher one’s DHT, the lower one’s PSA).
18. Testosterone replacement is better than exercise to reduce body fat, gain lean muscle and improve strength and effects of testosterone are improved with exercise (Synergistic effect)
19. The Dark Side of Testosterone Deficiency: Type 2 Diabetes & Insulin Resistance. This study demostrates that deficiency in testosterone contributes significantly to Type 2 Diabetes and Insulin Resistance. This leads to increased visceral fat deposits, increased inflammatory cytokines, promoting endothelia dysfunction and cardiovascular disease.
20. Low levels of testosterone play a role in the development of type 2 diabetes. Elevated insulin decreases testosterone levels resulting in a vicious cycle of worsening insulin resistance and reduced testosterone levels. Testosterone replacement breaks this cycle. It reduces the risk of diabetes and decreases insulin resistance.
Int J Obes Relat Metab Disord 2000
Mayo Clin Proc 2000 Jan;75 Suppl:S61-4
Diabetes Care. 2000 Apr;23(4):490-4
Metabolism 1997 May;46(5):526-9
21. Dihydrotestoterone with non-steroidal anti-inflammatory drugs (NSAIDS) kills prostate cancer cells.
22. Using HCG to boost testosterone levels results in significant improvement in prostate enlargement and symptoms.
23. Testosterone replacement decreases fat and increases lean muscle.
24. Testosterone replacement speeds healing and results in shortens hospital stays.
25. Pesticides reduce testosterone production in men.
Biology and Reproduction, 2003.



