Low testosterone has become an increasingly common topic in men's health, but misconceptions about the condition and its treatment persist. While testosterone replacement therapy (TRT) can improve quality of life for some men, experts say it's important to understand that low testosterone is more complex than a single number on a blood test.

CU Medicine urologist Jeff Morrison, MD, recently shared his expertise on the topic in an interview with TIME. He emphasizes that testosterone levels should never be evaluated in isolation. What is considered "normal" can vary from person to person, making symptoms, medical history and overall health important factors in determining whether further evaluation or treatment is appropriate.

When considering TRT, Dr. Morrison encourages patients to understand both the potential benefits and risks. As he told TIME, "There's no free lunch. There are side effects."

What is Low Testosterone and Why Does It Matter?

Testosterone is a hormone produced primarily in the testicles that plays an important role in many aspects of men's health. While it is often associated with sex drive, testosterone does much more than support sexual function.

The hormone helps regulate sperm production, maintain muscle mass and strength, support bone density and influence mood and energy levels. Healthy testosterone levels are also important for overall well-being and quality of life.

Testosterone levels naturally decline with age, typically beginning around age 30. However, age alone does not determine whether someone has low testosterone. Some men maintain healthy hormone levels and experience few symptoms as they get older, while others may develop testosterone deficiency and notice changes in their physical, sexual or emotional health.

What Are the Symptoms of Low Testosterone?

According to Dr. Morrison, the symptoms of low testosterone can be debilitating and affect multiple aspects of a man's physical, sexual and emotional well-being.

While symptoms vary from person to person, some of the most common signs of low testosterone include:

• Reduced sex drive (libido)
• Decreased spontaneous erections
  
• Fatigue or low energy
• Difficulty building or maintaining muscle mass
• Increased body fat
• Mood changes, including irritability or low mood
• Reduced motivation
• Difficulty concentrating

Many men seek care because they notice a gradual decline in energy, performance or overall quality of life. However, Dr. Morrison notes that these symptoms are not exclusive to low testosterone.

“Conditions such as poor sleep, chronic stress, depression, anxiety, obesity and certain medical conditions can cause similar symptoms,” said Dr. Morrison.

Because many symptoms overlap with other health issues, symptoms alone are not enough to diagnose low testosterone. A thorough evaluation, including a medical history, physical exam and appropriate laboratory testing, is necessary to determine whether low testosterone is truly the cause and whether treatment may be beneficial.

How is Low Testosterone Diagnosed?

Diagnosing low testosterone involves more than checking a single lab value. According to Dr. Morrison, physicians look at both a patient's symptoms and their hormone levels to determine whether testosterone deficiency may be present.

“The diagnosis of low testosterone requires two separate low testosterone test results along with symptoms,” said Dr. Morrison.

In addition to blood testing, physicians evaluate a patient's symptoms, overall health and medical history. Because factors such as obesity, sleep apnea and chronic illness can affect testosterone levels, diagnosis is based on more than a number alone.

How is Low Testosterone Treated?

Treatment for low testosterone depends on a patient's symptoms, hormone levels and overall health. According to Dr. Morrison, some men may benefit from lifestyle changes such as improving sleep, exercising regularly and managing their weight, while others may be candidates for testosterone replacement therapy (TRT).

For men with symptoms of testosterone deficiency and consistently low testosterone levels, TRT can help improve issues such as low libido, fatigue and decreased muscle mass.

“Before starting TRT, patients should understand both the benefits and potential risks,” said Dr. Morrison.

Possible side effects of TRT include:

• Acne
• Testicular shrinkage or atrophy
• Infertility
• Increased red blood cell counts
  

One important consideration is fertility. Testosterone replacement therapy can reduce sperm production and may affect a man's ability to have children. For that reason, men who are planning to start or grow their families should discuss their fertility goals with their physician before beginning treatment.

Can Testosterone Levels Be Improved Without TRT?

For some men, lifestyle changes can help improve testosterone levels and reduce symptoms. Dr. Morrison often encourages patients to focus on factors that support overall hormone health, including:

• Getting adequate, quality sleep
• Losing weight, when appropriate
• Exercising regularly
• Managing stress
• Limiting excessive alcohol use
• Managing chronic health conditions

“We as urologists have seen men improve their testosterone levels after they address the underlying cause,” said Dr. Morrison. “This could be anything from sleep apnea to drinking less alcohol.”

When to See a Doctor for Low Testosterone

Symptoms such as low libido, fatigue, erectile dysfunction and decreased muscle mass can affect quality of life and may be signs of low testosterone or another underlying health condition.

"Low testosterone can affect many aspects of a man's life," said Dr. Morrison. "We're here to help and have a variety of treatment options available."

If you're experiencing persistent symptoms, talk with your primary care provider or urologist. To learn more or schedule an appointment with Jeff Morrison, MD, contact CU Medicine Urology - South Denver at Highlands Ranch Pavilion 1 at 303-265-3940.

This content was reviewed on 8/11/2026 by Jeff Morrison, MD.