"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.
Though 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 loss of muscle mass.
While reduced testosterone is more common in older men, it may occur in younger guys as well. Luckily, all the causes of low testosterone in young guys are treatable, so in the event that you experience such symptoms at any given age, there's no reason to dismiss it.
For younger men, a fall in testosterone levels may be caused by some ailments, such as type 2 diabetes, chronic liver or liver disease, COPD or other lung disease, or pituitary 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 that could cause low testosterone is hemochromatosis, which makes 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," says Bruce Gilbert, MD, PhD, an adjunct clinical professor of urology and reproductive medicine at Weill Cornell Medical College and director of reproductive and sexual medicine in the Smith Institute for Urology of their North Shore-LIJ Health System.
Other causes of low testosterone in men younger than 50 contain adrenal gland tumors, HIV disease, and radiation treatment or chemotherapy for cancer.
Doctors categorize causes of low testosterone as secondary or primary.
"Primary hypogonadism stems from a problem in the testicles," Samadi states.
Is It 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.
Your doctor can diagnose low testosterone with a blood test.
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 a urologist or endocrinologist.
Not everyone with low testosterone needs treatment. "When it comes to treating low testosterone in younger men, we usually reserve treatment for those who have symptoms, such as tiredness 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 usually used only in the short term, and when a doctor has close observation and knowledge of the patient," Gilbert says.
An important consideration for younger men before getting treatment is fertility. "You don't want to offer supplemental testosterone to guys who are interested in being fertile since 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. "Hence, men of reproductive age should think about alternatives which may improve their testosterone in addition to maintain their sperm production," he says. One such alternative is a class of drugs called selective estrogen receptor modulators (SERMs).
Other remedies for low testosterone include weight loss and other lifestyle modifications, like eating healthy and raising exercise.
The main point, though, is that if you have low testosterone symptoms, then it is very important to see your doctor. Then, your doctor can rule out potentially more serious causes of your symptoms, such as hypertension or a thyroid problem, and give treatment that could improve your energy and quality of life.