"After age 30, most men begin to experience a gradual decline in testosterone," states David Samadi, MD, chairman of the urology department at Lenox Hill Hospital in New York City.
Although testosterone levels never reach zero (as estrogen levels do in women during menopause), low testosterone levels men to experience symptoms such as fatigue, low libido, and reduction of muscle mass.
While low testosterone is more common in older men, it can occur in younger guys as well. Fortunately, every one of the causes of low testosterone in young guys are treatable, so if you encounter such symptoms at any given age, there's no reason to ignore it.
For younger guys, a drop in testosterone levels can be caused by some ailments, such as type 2 diabetes, chronic liver or kidney disease, COPD or other lung disease, or adrenal gland issues, according to Dr. Samadi.
Genetic causes of low testosterone in males include the ailments Klinefelter syndrome, Kallmann syndrome, Prader-Willi syndrome, and Myotonic dystrophy. Another disorder which can result in low testosterone is hemochromatosis, making the body shop too much iron.
"Low testosterone can also result when something happens, like trauma or steroid use, that prevents the testes from making the hormone," states Bruce Gilbert, MD, PhD, an adjunct clinical professor of urology and reproductive medicine at Weill Cornell Medical College and director of reproductive and reproductive medicine at the Smith Institute for Urology of the North Shore-LIJ Health System.
Other causes of low testosterone in males younger than 50 include pituitary gland tumors, HIV disease, and radiation therapy or chemotherapy for cancer.
Doctors categorize causes of low testosterone as primary or secondary.
"Primary hypogonadism stems from a problem in the testicles," Samadi states. In secondary hypogonadism, the testicles are normal but function improperly because of a problem with the hypothalamus or pituitary gland."
Can It Be Low Testosterone?
Regardless of the reason, low testosterone symptoms would be the same.
"Symptoms include low libido, erectile dysfunction, fatigue, decreased mental acuity and moodiness," Dr. Gilbert states.
If your blood test reveals low testosterone (usually defined as a level lower than 300 ng/dL), the doctor may treat you or refer you to a specialist, such as an urologist or endocrinologist.
"When it comes to treating low testosterone in older men, we usually reserve treatment for people who have symptoms, such as fatigue and reduced libido," Gilbert says.
In men who don't make the hormone in their testes because of a condition such as Klinefelter syndrome, or those who have lost their testes because of cancer, the only option is testosterone replacement therapy.
In these circumstances,"treatments are often used just in the short term, and when a physician has close observation and understanding of the individual," Gilbert says.
An important consideration for younger men before getting treatment is fertility. "You don't wish to offer supplemental testosterone to men who are interested in being fertile because it can turn off sperm production," Gilbert says.
Once a young man goes off testosterone supplementation, there's a chance his sperm count will never return to what it was before he started. "Therefore, men of reproductive age should consider alternatives which may improve their testosterone as well as maintain their sperm production," he states. One such alternative is a category of drugs known as selective estrogen receptor modulators (SERMs).
Other treatments for low testosterone include weight loss and other lifestyle modifications, like eating healthier and raising exercise.
The main point, though, is that if you've got low testosterone symptoms, it's important to see your doctor. Then, your doctor can rule out more serious causes of your symptoms, including high blood pressure or a thyroid problem, and offer treatment that could enhance your power and quality of life.