Men's Health

Low Testosterone In Men: How Exactly Does It Happen?

Learn more about how testosterone levels decrease the older you get. Your age plays into your symptoms of low testosterone, too.

Dr. Nayan Patel

Low Testosterone in Men

Testosterone is a vital male sex hormone and helps men maintain bone density, muscle mass and strength, sex drive, sperm production, and facial and body hair. As men age, their testosterone level gradually declines around 1% every year after age 30. And, a man’s testosterone level will fluctuate throughout the day with the highest level peaking in the morning. So, how does low testosterone happen? It’s simple: the testicals aren’t producing enough testosterone needed to function.

There are other names for low testosterone (male hypogonadism) like:

  • Primary hypogonadism
  • Secondary hypogonadism
  • Hypergonadotropic hypogonadism
  • Hypogonadotropic hypogonadism
  • Testosterone deficiency syndrome
  • Testosterone deficiency

Low T also tends to happen with age but, according to the American Urological Association, roughly 40% of men aged 45 and above have low testosterone. If a man isn’t producing enough testosterone in his body, he’ll likely experience hypogonadism – or Low T. Certain conditions like diabetes and obesity tend to go hand-in-hand with men who also have low testosterone. The threshold for a low testosterone level as defined by the American Urology Association is a low blood testosterone with less than 300 nanograms per deciliter (ng/dL) but not everyone is in agreement with that number and many providers will look at symptoms of low testosterone along with the blood testosterone level before providing a diagnosis.

Symptoms of Low Testosterone

It’s widely known that testosterone levels decrease the older you get but your age plays into your symptoms of low testosterone, too. Symptom severity levels will also be different from person-to-person. While there isn’t one specific symptom of low testosterone that is consistent among men, there are some common low testosterone signs to be aware of.

Top 10 Low Testosterone Signs

Low Sex Drive can be caused by many things like stress and the aging process but since testosterone plays a pivotal role in your sex drive, men with Low T will likely experience a steep decline in being interested in sex.

Hair Loss can also be attributed to the aging process, stress, and heredity but someone experiencing low testosterone will likely also lose body hair and facial hair. In addition, low testosterone levels can also make it hard to grow facial hair adequately.

Frequent Mood Changes are a cornerstone symptom of hormone imbalances and fluctuations. Any irregularity within testosterone or TSH (Thyroid Stimulating Hormone) can result in mood swings but low testosterone contributes to feelings of sadness and depression. 

Erectile Dysfunction affects around 30 million men and occurs when a man can’t attain or sustain an erection that’s firm enough for sexual intercourse. When erectile dysfunction becomes routine, it’s time to speak to a provider to find the root cause. 

Decreased Muscle Mass is often coupled with an increase in body fat - usually at the same time - because testosterone contributes to building muscle but doesn’t necessarily contribute to muscle strength or function. Low testosterone can also impact the body’s metabolism, which can increase fat within the body.

Hot flashes aren’t just for menopausal women - men with low testosterone can experience hot flashes, too! It’s often coupled with night sweats, reddening of the skin, and heavy sweating.

Fatigue shouldn’t be confused with being tired from a poor night’s sleep. Being tired and fatigued are very different. Men with low testosterone often report extreme fatigue with low energy, which can make it hard to work through everyday tasks. It can also place the body in a stressful state, which can increase cortisol levels. If cortisol levels are elevated for a long period of time, it can lead to adrenal fatigue which can adversely affect the body’s ability to regulate hormones. When cortisol levels are too high, it can also affect testosterone. 

Memory loss can happen as part of the normal aging process but doctors theorized that lower testosterone levels could contribute to affected memory. However, there is some conflict within the research world on this. A 2017 study on testosterone supplements did not find memory improvements among the men with Low T who took testosterone vs those who took a placebo. But a 2019 review of studies found that testosterone supplementation is linked with improved memory in older men who have Low T. 

Decreased semen volume typically occurs when someone has lower levels of testosterone because the testosterone is responsible for ensuring the prostate and seminal vesicles work properly. When those organs don’t work effectively, sperm can’t be produced at an optimum level. 

Reduced bone density and osteoporosis are both found in men with low testosterone because testosterone helps build bones and strengthen them. This can make older men with lower bone volume more susceptible to broken bones when they also have lower testosterone levels.

Low Testosterone Treatments

While there are some definitive symptoms of low testosterone, getting a diagnosis isn’t always easy. Testosterone levels aren’t regularly checked during annual physicals and symptoms are often brushed off as age or stress-related. If you are experiencing any of the symptoms mentioned above, take our free testosterone assessment to uncover what your doctors might be missing. It’s important to understand what you’re up against before you dive into low testosterone treatments.

Since every person’s symptoms of Low T are different, opt for a low testosterone treatment that is personalized to fit your symptoms and lifestyle. Low testosterone treatment options include:

  • Testosterone Replacement Therapy (TRT)
  • Bioidentical Testosterone Replacement Therapy (BTRT)
  • Testosterone Skin Patches
  • Testosterone Gels
  • Hormone Injections
  • Testosterone Pellets
  • Natural Supplements

Treating low testosterone shouldn’t be a one-size-fits-all approach. A bioidentical testosterone replacement therapy, or BTRT, may give you the best outcome because it mimics the natural testosterone produced in the male body. And you should work with a provider who can be readily available as needed to talk through changes you experience and side effects while also keeping tabs on your testosterone levels. 


1. Effects of Testosterone Supplementation on Separate Cognitive Domains in Cognitively Healthy Older Men


Reclaim Your Testosterone Balance