What Causes Low Testosterone Levels?

Clinical study suggests that low testosterone levels in men are strongly linked to all-cause mortality due to cardiovascular dysfunction, diabetes type 2 and other related issues. It has also been statistically proved that testosterone replacement can minimize the risk of complications. Low testosterone levels can occur due to numerous reasons including certain diseases and even certain prescription and street drugs. It is imperative to mention that low testosterone levels are not always a sign of an underlying disease. For example, a fair percentage of men suffers from physiological hypogonadism i.e. declining testosterone levels caused by age related decline in the production of testosterone. This type of hypogonadism is more frequently seen in men over 40 years of age. However, this age dependent reduction does not occur at an alarming rate. Sometimes low T can be due to unknown reasons.

Following are the disease conditions or disorders that can markedly reduce testosterone in men and boys:

Chronic obstructive lung disease
Chronic renal (kidney) disease
Chronic liver disease
HIV/AIDS
Autoimmune diseases
Infections (for example, mumps)
Heart failure
Obesity and metabolic disorders
Type 2 diabetes
Injured testicles
Testicular cancer or its treatment
Prolactinoma-prolactin secreting tumor

Can Drugs Or Pharmacological Agents Aggravate The Risk Of Hypogonadism?

About 2-20% cases of hypogonadism are associated with abuse or overuse of certain drugs. Based on the results of a new study, drugs that are linked with reduction in the testosterone levels are:

Chemotherapeutic drugs for cancer treatment
Opioids
Corticosteroids (glucocorticoids)
Alcohol

Obesity And Low Testosterone Levels

Having BMI (body mass index) greater than 30 kg/m² is termed as obesity. It is quite prevalent across the globe, including United States and is considered one of the biggest culprits of abnormally low testosterone levels in males.

A 4-5kg/m2 rise in BMI can reduce testosterone by 10%, says Journal of Clinical Endocrinology & Metabolism,2007.

A year later another study published in the same journal according to which, wider waist contributes significantly to abnormal testosterone metabolism and the effects are more deleterious than advancing age. Fortunately, clinical study indicates that shedding off extra pounds can boost testosterone levels. A study published in the clinical journal Diabetes, Obesity and Metabolism suggests that men who shed weight via 9-week low calorie diet and exercise regains normal testosterone levels. Undergoing bariatric surgery also reduces extra weight very efficiently, giving prompt results. Losing weight moderately is also found to be beneficial. Men who lose weight through moderate exercise and diet program also ends up increasing their testosterone levels modestly.

Low Testosterone In Women:

Low T can occur in women too! But fortunately, low testosterone is not always symptomatic and doesn’t produce serious side effects like that in men. Low T in women can be due to various reasons such as:

Hysterectomy (surgical removal of uterus)
Premature ovarian failure
Ovaries being removed surgically
Adrenal insufficiency
Women who consume a combination of oral contraceptives
Hypopituitarism (a disorder where hormonal secretion from pituitary gland is reduced)
Impaired interaction between pituitary gland, hypothalamus and adrenal glands

References

Khaw, K. T., Dowsett, M., Folkerd, E., Bingham, S., Wareham, N., Luben, R., … & Day, N. (2007). Endogenous testosterone and mortality due to all causes, cardiovascular disease, and cancer in men European prospective investigation into cancer in Norfolk (EPIC-Norfolk) prospective population study. Circulation, 116(23), 2694-2701.
Wang, C., Jackson, G., Jones, T. H., Matsumoto, A. M., Nehra, A., Perelman, M. A., … & Cunningham, G. (2011). Low testosterone associated with obesity and the metabolic syndrome contributes to sexual dysfunction and cardiovascular disease risk in men with type 2 diabetes. Diabetes care, 34(7), 1669-1675.
Laughlin, G. A., Barrett-Connor, E., & Bergstrom, J. (2008). Low serum testosterone and mortality in older men. The Journal of Clinical Endocrinology & Metabolism, 93(1), 68-75.