What is testosterone?

It is a sex hormone that is produced by the testes under the control of hormones that come from the pituitary gland which sits right above your nose.  Testosterone is not only needed to turn boys into men, it is also needed to produce sperm. Women also produce varying levels of testosterone although it is much lower than in males.

What does testosterone do?

Testosterone production inside the womb, dictated by the Y chromosome, is what separates males from females.  There are rare conditions where that may not happen correctly, but they are beyond the scope of this blog.  At the time of puberty, testosterone levels surge to cause increased bone and muscle mass, testicular and penile growth, increased libido, deepening of the voice, facial and body hair development, and the start of sperm production.

What are the symptoms of low testosterone?

Symptoms such as fatigue, decreased muscle strength, low libido, and poor “get-up-and go” are common complaints men have. However, those are not specific to low testosterone and can simply be due to poor conditioning (out of shape), medications, or obesity. Other symptoms including gynecomastia or “man boobs”, shrinking testicles, and/or lack of morning erections may raise concerns about low testosterone also.

How do you test testosterone levels?

There are 2 blood tests that check testosterone levels, free testosterone and total testosterone.  The most accurate test is the total testosterone. It must be drawn within 2 hours of waking up for an accurate diagnosis. Testosterone levels drawn outside of this time period are never accurate because the levels drop throughout the day and reach their lowest levels in the late afternoon. An abnormal test should be repeated to confirm the diagnosis because factors such as an illness could falsely lower your levels. An abnormal level is usually anything less than 250 or 300 depending on the lab that is testing it. Free testosterone levels can also be drawn to confirm the diagnosis also although it typically isn’t needed initially. 

What causes low testosterone levels?

There are 3 categories that could cause low testosterone or hypogonadism.  The first is primary hypogonadism.  This is a problem with the testicle’s ability to make testosterone. It is usually rare, and most men are born with that issue. Chemotherapy, however, can also cause primary hypogonadism.

Secondary hypogonadism is more common.  Most men who have this as a cause are usually not elderly. This is often caused by obesity or the use of narcotics.  It can also be caused by a brain tumor involving the pituitary gland.

The 3rd category is a drop due to normal aging.

Does testosterone replacement work for low libido or erectile dysfunction? 

The results are mixed. If you have normal testosterone levels and suffer from erectile dysfunction, more testosterone will likely not help. There may be other reasons for your erectile dysfunction such as uncontrolled diabetes, psychological, poor conditioning. If your levels are low however, there is a chance it may help.

Does testosterone help with bone mass or muscle strength?

Although it does increase bone mass in older men who have low testosterone levels, it doesn’t exactly prevent fractures and there isn’t a clear reason why.  In terms of muscle strength, although body builders and athletes with normal levels use testosterone to bulk up and build strength, in older men with low levels it doesn’t build strength. 

Is taking testosterone safe?

The short answer is that no one really knows. A widely publicized study in 2015 was stopped early because it appeared that men who were taking supplemental testosterone were dying from heart attacks and strokes much more frequently than the men who weren’t. As researchers later looked deeper into it the study, it appears to not be as big of a problem as once thought. However, no medication is 100% safe, testosterone included. My advice is to make sure you have an accurate diagnosis and discuss your risks with your physician prior to initiating treatment.   

Who should not get testosterone replacement therapy?

Men who have prostate cancer, breast cancer, a high red blood cell count, or a PSA level more than 4 shouldn’t take it. Men who already have heart disease, a history of strokes, congestive heart failure, enlarged prostate, or untreated sleep apnea should have an intensive risk assessment by their primary care physician or urologist prior to initiating treatment as it could make those symptoms worse.

How is testosterone replaced?

Testosterone is replaced by intramuscular injections (shots), patches, or gels.  Testosterone is a hormone and is broken down by acids in your stomach so pills will not work. Testosterone replacements are very expensive and can run you in the hundreds of dollars per month depending on which formulation you use. Injections are the cheapest whereas the patches and gels are the most expensive.

How to naturally boost testosterone:

Most of the time, as long as there isn't a testicular or pituitary gland problem you can boost your levels and your libido by putting in work at the gym or on the track. Cutting body fat and adding muscle mass can increase testosterone production. Also, getting off of narcotics such as Morphine and Hydrocodone will help.   

What able "testosterone boosters"?

I see those commericial just as much as you do and honestly from a doctor's prespective, I would be very weary of taking them. They are unregulated and no one really knows what's in those pills.  What you don't know can hurt you.  

Keith Perkins Jr., MD Dr. Perkins is a double board certified physician in Internal Medicine and Pediatrics and is the solo owner of Premier Internal Medicine and Pediatrics in Selmer, TN. He has been a practicing physician since 2011 and absolutely loves primary care.

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