Many males over the age of 30 suffer from low testosterone, the primary male sex hormone related to overall male health. When within normal testosterone range, males display an increase in protein synthesis and lean muscle development as well as better overall physical and psychological health. Low testosterone levels have been found to correlate with physiological disorders ranging from Cardio Vascular Disease to Type II Diabetes. Men suffering from low testosterone have even been observed to exhibit psychological symptoms such as anxiety and depression. Males over the age of 30 who suffer from low testosterone are eligible for testosterone replacement therapy, commonly known as TRT. TRT is steadily becoming a standard in treatment for males exhibiting appropriate symptoms. Though much more research is needed, current data supports the use of TRT treatment in symptomatic males over 30 to improve overall male health.

Testosterone, the primary male sex hormone, is secreted by the endocrine system and is responsible for overall men’s health. Specifically secreted by the gonads and dispersed throughout the body, testosterone is responsible for such things as development of lean muscle mass, regulation of glucose, and lipid metabolism (Kelly, D. and Jones, T. 2013). When within normal range testosterone helps to regulate and maintain these, and other, body processes. As men age the available levels of free testosterone decrease and regulation of these processes begins to fail. Research has begun to show a correlation between low testosterone and some specific physiological disorders. Some of the physiologic disorders found to correlate with low testosterone are Cardio Vascular Disease, Type II Diabetes, and Metabolic Syndrome (McGill et al 2013).

In the case of CVD (Cardio Vascular Disease), studies have shown that testosterone enhances myocardial function and TRT in middle-aged men reduces total cholesterol. The same studies have shown the correlation between low testosterone and CVD risk factors. The increase of these risk factors seems to coincide with an increase of cardio vascular mortality rates as well (Corona et al 2011). However, with the increase in TRT, more data is being recorded in order to further assess this relationship. Though the correlation between cardio vascular mortality and low testosterone can be made, more studies are required in order to identify a specific cause and effect relationship. Also, testosterone directly affects lipid metabolism, myocardial function, and total cholesterol, which are all risk factors for CVD (Corona et al 2011). Because of the effect of low testosterone on these body processes, an individual with low testosterone would fit into a category of increased risk for CVD. This increased risk seems to lead to the logical conclusion that the decrease in testosterone levels will increase the risk of CVD and therefore increase cardio vascular mortality rate. Only more long term research will tell.

Another disorder displaying a link between low testosterone and increased risk is Type II Diabetes. Men with Type II Diabetes have been found to have lower than normal levels of free testosterone (Dandona, P. and Dhindsa, S. 2011). Free testosterone is the term given to the accessible testosterone content found in the blood stream. As this level decreases the body’s fat composition begins to change leading toward obesity. Obesity and the high prevalence of lipids lower the efficiency of the body to metabolize glucose and thus decreasing insulin regulation.  This process is known as obesity induced insulin resistance which is a common factor for Type II Diabetes (Kang, H. 2013). The question which remains is how testosterone specifically affects the body’s lipid metabolism and fat composition. Though there is a direct correlation and strong evidence to support that low levels of free testosterone increase the risk of Type II Diabetes, more research is required in order to discover the specifics of this relationship.

Metabolic Syndrome is a disease characterized by a combination of systemic dysfunctions. The dysfunctions most commonly associated with this disorder are obesity, insulin resistance, and hypertension. Like CVD and Type II Diabetes, obesity and insulin resistance have been shown to correlate with low levels of testosterone. Research suggests that low testosterone and hypertension share an inverse relationship (Tsujimura, A. 2013). This relationship indicates that as blood serum testosterone levels decrease, hypertension increases. Though the exact effect of testosterone on blood pressure is still unclear, patients treated with TRT have shown a significant decrease in systolic and diastolic blood pressure (Tsujimura, A. 2013).

Testosterone has also been shown to have an effect on psychological behavior within males (Aydogan et al 2012). Specifically, anxiety and depression appear to be effected by the diminished presence of free testosterone in the blood stream. Recent studies indicate that patients suffering from low testosterone have a higher incidence of anxiety and depression (Pantalone, K. and Faiman, C. 2012). They also generally display a poorer quality of life when compared to patients receiving TRT. Some of this seems to be attributed to sexual dysfunction. Since testosterone is directly related to sexual function, and sexual dysfunction has been shown to cause both depression and anxiety, some argue that the sexual dysfunction caused by low testosterone is the primary cause for the elevation of anxiety and depression. Without conclusive direct evidence however, the question still stands to how testosterone directly affects personal mood. However, personal mood, including anxiety and depression, have been shown to improve with administered TRT indicating that the link does exist (Aydogan et al 2012).

What constitutes normal and low testosterone levels vary from source to source, but the effects of testosterone within an optimal range seems to be consistent. The National Institute of Health has stated that the normal range for blood serum testosterone is between 300 ng/dl (nanograms per deciliter) and 1000 ng/dl (Topiwala, S. 2012). While they are in this range, healthy subjects are said to exhibit normal physiological and psychological stasis. However, since this range consists of a 700 ng/dl span there still remains much debate as to what is optimal versus what is low. While when they are evaluated within a given optimal range, male subjects have been shown to attain a higher level of protein synthesis and lipid metabolism (Kelly, D. and Jones, H. 2012). A higher level of protein synthesis leads to an increase in lean mass as well as muscle density. The increase in lipid metabolism leads to an overall reduction in body fat with specifically high reductions found in the waste area and bloodstream (Bhattacharya, R.K. 2012). The reduction in bloodstream lipids has been shown to reduce risk of many of the disorders listed previously (Corona et al 2011).

Males over the age of 30 who suffer from decreased levels of free testosterone are eligible for TRT. Though the range of normal is great, diagnosis of symptomatic presentation and/or a blood testosterone level of 200 ng/dl or lower are indicative of plausible treatment requirements. Since many of the symptomatic results can be caused by other disorders, the combination of symptom diagnosis and blood testing is generally applied. Once a baseline of symptoms and blood tests establish deficiency, treatment through transdermal gels or intramuscular injections is administered. Administration of TRT through these methods is usually evaluated for effectiveness over the span of 6 to 12 months and titrated to the desired effect (Giannoulis et al 2012). The longer span of treatment titration allows providers to assess the critical changes over the initial psychosomatic response (Nigro, N. and Christ-Crain, M. 2012). As the patient receives treatment over time the initial psychosomatic response diminishes and the clinical responses can be more accurately assessed.

TRT is steadily becoming a standard in the treatment of low testosterone for males over 30. Those who present with the appropriate symptoms, and low blood testosterone level tests, are eligible for this treatment and its benefits. Since TRT is becoming more common, more funding is going toward research in the exact links between low testosterone and its correlating disorders. With time and perseverance many of the gaps in information should begin to be filled and appropriate data identified. Though TRT should not be considered a cure-all for aging males, it should be considered, evaluated, and researched for its potential benefits and contra-indications.

Works Cited

Kelly, D. and Jones, T. 2013. Testosterone: a metabolic hormone in health and disease. Journal of Endocrinology Society for Endocrinology in Great Britain. 217(3): R25-R45

McGill et al. 2013. Androgen deficiency in older men: Indications, advantages, and pitfalls of testosterone replacement therapy. Cleveland Clinic Journal of Medicine. 79: 797-806

Corona et al. 2011. Hypogonadism as a risk factor for cardiovascular mortality in men: a meta-analytic study. European Journal of Endocrinology. 165: 687-701

Dandona, P. and Dhindsa, S. 2011. Update: Hypogonadotropic Hypogonadism in Type 2 Diabetes and Obesity. Division of Endocrinology, Diabetes, and Metabolism, State University of New York at Buffalo and Kaleida Health. 96(9):2643–2651

Kang, H. 2013. Beyond the male sex hormone: deciphering the metabolic and vascular actions of testosterone. Journal of Endocrinology Graduate Institute of Clinical Medical Sciences, Hormone Research Center, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan. 217(3): C1-C3

Tsujimura, A. 2013. The Relationship between Testosterone Deficiency and Men’s Health. World Journal of Men’s Health Department of Urology, Osaka University Graduate School of Medicine. 31(2): 126-135

Aydogan et al 2012. Increased frequency of anxiety, depression, quality of life and sexual life in young hypogonadotropic hypogonadal males and impacts of testosterone replacement therapy on these conditions. Endocrine Journal Japan Endocrine Society. 59 (12), 1099-1105

Pantalone, K. and Faiman, C. 2012. Male hypogonadism: More than just a low testosterone. Cleveland Clinic Journal of Medicine. 79(10): 717-725

Topiwala, S. 2012. Testosterone. Medline Plus National Institutes of Health [Internet]. [Cited 2013 Oct 24]. Available from:

Bhattacharya, R.K. 2012. Testosterone replacement therapy among elderly males: the Testim Registry in the US (TRiUS): Clinical Interventions in Aging. 12(7): 321-330

Giannoulis et al. 2012. Hormone Replacement Therapy and Physical Function in Healthy Older Men. Time to Talk Hormones? Endocrine Reviews. 33(3):314–377

Nigro, N. and Christ-Crain, M. 2012. Testosterone treatment in the aging male: myth or reality? The European Journal of Medical Sciences Swiss Medical Weekly. 142(w13539): 1-6