"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 can occur in younger guys as well. Fortunately, all the causes of low testosterone in young guys are treatable, so in the event that you encounter such symptoms at any age, there is no reason to ignore it.
Causes of Low Testosterone in Younger Men
For younger guys, a drop in testosterone levels can be brought on by some illnesses, including type 2 diabetes, diabetes, chronic liver or kidney disease, COPD or other lung disorder, or adrenal gland problems, based on Dr. Samadi.
Genetic causes of low testosterone in males include the diseases Klinefelter syndrome, Kallmann syndrome, Prader-Willi syndrome, and Myotonic dystrophy. Another disease that can result in low testosterone is hemochromatosis, which makes the body store 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 sexual medicine at the Smith Institute for Urology of their North Shore-LIJ Health System.
Additional causes of low testosterone in men younger than 50 include pituitary gland tumors, HIV infection, 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 says. "This could be from a developmental issue, injury to the testicles, or radiation or chemotherapy treatment.
Can It Be Low Testosterone?
Irrespective of the cause, low testosterone symptoms are 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 a urologist or endocrinologist.
Treatments for Low Testosterone in Younger Men
Not everyone with low testosterone needs treatment. "When it comes to treating low testosterone in older guys, we generally reserve treatment for people who have symptoms, such as tiredness and reduced libido," Gilbert says.
In these circumstances,"therapies are often used just in the brief term, and if a physician has close monitoring and understanding of the individual," Gilbert says.
An important consideration for younger men before getting treatment is fertility. "You do not want to give supplemental testosterone to men who want to be 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 think about alternatives that might increase their testosterone as well as preserve their sperm production," he says. One such alternative is a class of drugs called selective estrogen receptor modulators (SERMs).
Other treatments for low testosterone include weight loss and other lifestyle changes, such as eating healthy and raising exercise.
The main point, however, is that in the event that you've got low testosterone symptoms, it's important to see your doctor. Then, your doctor can rule out potentially more serious causes of your symptoms, including hypertension or a thyroid problem, and give treatment that could enhance your energy and quality of life.