Do you have a testosterone deficiency?

Naturally testosterone declines with age and as a result you might get the disease known as hypogonadism. Hypogonadism is due to producing low testosterone or a testosterone deficiency which may damage the hypothalamus, pituitary gland or testicles by inhibiting the hormone secretion and testosterone production. Insufficient testosterone can lead to abnormalities in muscle and bone development, underdeveloped genitalia, and diminished virility.

Testosterone is the androgenic hormone primarily responsible for normal growth and development of male sex and reproductive organs, including the penis, testicles, scrotum, prostate, and seminal vesicles. It makes possible the development of secondary male sex characteristics such as musculature, bone mass, fat distribution, hair patterns, laryngeal enlargement, and vocal cord thickening. Additionally, normal testosterone levels maintain energy level, healthy mood, fertility, and sexual desire.

The testes produce testosterone regulated by a complex chain of signals that begins in the brain. This chain is called the hypothalamic-pituitary-gonadal axis. The hypothalamus secretes gonadotropin-releasing hormone (GnRH) to the pituitary gland in carefully timed pulses (bursts), which triggers the secretion of leutenizing hormone (LH) from the pituitary gland. Leutenizing hormone stimulates the Leydig cells of the testes to produce testosterone. Normally, the testes produce 4–7 milligrams (mg) of testosterone daily.

Testosterone production increases rapidly at the onset of puberty and decreases rapidly after the age of 50. Studies show that about 13 million men in the United States experience testosterone deficiency and less than 10% receive treatment for the condition. Men that are obese, have diabetes or hypertension may be twice as likely to have low testosterone levels.

The possibilities of testosterone therapy are enticing — increase your muscle mass, sharpen your memory and mental focus, boost your libido, and improve your energy level. As you get older, testosterone therapy may sound like the ultimate anti-aging formula. But health benefits from testosterone therapy aren't quite so clear-cut.

Before you buy into the tempting claims, find out what's known — and not known — about testosterone therapy so that you can make the best decision for your long-term health.

Your doctor can prescribe a synthetic version of testosterone. Testosterone therapy using testosterone replacement medications may be necessary for men who have very low levels of testosterone (hypogonadism). Testosterone therapy medications are available as injections, patches and gels.

It's not clear that naturally falling testosterone levels cause any signs and symptoms in men. Studies of men who have very low levels of testosterone due to diseases and treatments may offer some clues to the role testosterone plays in a man's body as he ages. According to those studies, testosterone deficiency can have several effects on the body, including:

• Decreased sexual function
• Loss of bone density
• Loss of muscle mass
• Increase in fat mass
• Reduced muscle strength
• Memory loss
• Mood changes and depression

Some men experience these signs and symptoms, but don't have unusually low levels of testosterone. Others may have low levels of testosterone, but don't experience any signs and symptoms that would prompt them to seek treatment.

Some men believe that taking testosterone medications may help them feel younger and more vigorous as they age. But while studies show that testosterone therapy can restore your testosterone level to that of your youth, it isn't clear that there's any benefit to this. And it isn't clear if a higher testosterone level can help you live longer.

Few rigorous studies have examined testosterone therapy in men with healthy testosterone levels. Some small studies have revealed unclear results. For instance, studies found that healthy men who take testosterone medications saw their muscle mass increase, but in most studies the men weren't any stronger after testosterone therapy.

Not enough study has been done to determine the risks of testosterone therapy in men with normal testosterone levels. In theory, a higher than normal testosterone level could increase a man's risk of prostate cancer or an enlarged prostate (benign prostatic hyperplasia). But studies haven't determined whether testosterone therapy could cause these complications.

Studies show testosterone therapy can cause sleep apnea in some men. This condition causes you to continually start and stop breathing as you sleep. Testosterone therapy may also cause your body to make too many red blood cells (polycythemia), which can increase your risk of heart disease.

Consider these pros and cons when evaluating testosterone therapy:

Potential benefits	Potential risks
Improve muscle mass and strength Increase bone mineral density Thicken body hair and skin Improve sexual desire Boost energy Decrease irritability and depression Improve cognitive function	Cause skin reactions Cause fluid retention Cause baldness Cause or aggravate sleep apnea Stimulate noncancerous growth of the prostate and cause or worsen urinary symptoms Stimulate growth of prostate cancer that's already present Enlarge breasts Stimulate growth of breast cancer that's already present Cause testicle shrinkage Limit sperm production Stimulate excess blood production Cause acne

If you're concerned that you might have a hormone deficiency, talk to your doctor. A decline in testosterone that falls below normal values may be a reason to take supplemental testosterone. There is some controversy about whether testosterone therapy should be used in men who have naturally lower testosterone levels as a result of aging. It remains unclear whether restoring the testosterone levels to those of youth benefits older men.