Osteoporosis is a progressive bone disease. It can lead to brittle bones and an increased risk of fracture if left untreated. The International Osteoporosis Foundation estimates that 1 in 3 women and 1 in 5 men over age 50 will experience an osteoporotic fracture in their lifetime.

Testosterone is an important hormone for maintaining healthy muscles and bones. Researchers are still learning how testosterone levels affect bone density.

Current evidence suggests that men with testosterone deficiency have a higher risk of developing osteoporosis and experiencing fractures. But more research is needed to confirm the relationship between low testosterone levels and the development of osteoporosis.

Read on to learn more about the connection between testosterone levels and osteoporosis.

Your body is constantly building and breaking down bone tissue. This process is known as bone remodeling. Osteoporosis develops when your body breaks down bone tissue faster than it builds it up.

Three types of cells are involved in the process of remodeling:

  • Osteoblasts lay down new bone tissue.
  • Osteoclasts reabsorb bone.
  • Osteocytes regulate bone homeostasis (the redevelopment and reabsorption stages of bone growth).

Some of these cells may have receptors for androgen hormones. Testosterone is thought to modify bone mass by activating these receptors.

Testosterone and osteoporosis in men

People undergoing menopause experience a sharp decrease in estrogen levels. But as men age, they experience a more gradual decline in their hormone levels. Testosterone levels decrease by about 1% per year after about age 30 or 40.

Testosterone deficiency is the primary cause of osteoporosis in men. It can also cause other symptoms, such as:

In older men, osteoporosis commonly causes spine fractures and hip fractures.

Bone mineral density has a close relationship with testosterone levels in men. When men undergo androgen deprivation therapy for prostate cancer, a common side effect is osteoporosis. Bone mineral density tends to decrease by 2% to 8% in the first year after treatment.

Research suggests that men who have low testosterone levels have a higher risk of fracture than men with testosterone in an average range. However, it’s not clear whether testosterone supplementation decreases the risk of fracture.

Testosterone and osteoporosis in women

In women, a primary cause of osteoporosis is estrogen deficiency from menopause.

Women produce a small amount of testosterone in their ovaries and adrenal glands. Bone growth and maintenance are significantly influenced by testosterone in women as well as men.

In a 2015 study involving 64 postmenopausal women, researchers found that testosterone levels didn’t affect bone mineral density in this group.

Researchers noted that some previous studies showed high androgen levels were associated with increased bone mineral density in premenopausal women.

Research suggests that bone mineral density seems to be influenced by testosterone levels and exercise habits. Testosterone levels may naturally decline in men starting around age 30 or 40, which may lead to testosterone deficiency in middle age.

Osteoporosis may be a side effect of androgen deprivation therapy (ADT) used to treat prostate cancer. ADT involves reducing testosterone and other androgen hormones with drugs or surgery.

Anywhere from 9% to 53% of men are thought to develop osteoporosis after ADT.

Some genetic conditions, such as Turner syndrome and Klinefelter syndrome, can also result in testosterone deficiency. Other causes of low testosterone can include:

Secondary causes of low testosterone, which are caused by problems with the pituitary gland or hypothalamus, may include:

  • Kallmann syndrome
  • pituitary disorders
  • HIV
  • obesity
  • surgery
  • trauma
  • stress

Women produce testosterone primarily in their ovaries and adrenal glands. Causes of low testosterone in women can include:

Osteoporosis doesn’t usually cause symptoms until it leads to a bone fracture. Low testosterone tends to cause more noticeable symptoms.

Diagnosing low testosterone

A blood serum test is used to determine testosterone levels. A blood sample is usually drawn with a needle through a vein in your arm. A lab will determine whether your testosterone levels are below the normal range.

Diagnosing osteoporosis

Osteoporosis is usually diagnosed with a bone mineral density scan. Typically, this exam is performed with dual-energy X-ray absorptiometry (DEXA). DEXA measures the number of X-rays that are absorbed by your tissues and bone to estimate your bone mineral density.

During the test, you lie on a table and the scanner passes over your bone. Often, only your hips and spine are evaluated.

Prescription medications may slow bone loss and reduce the risk of fracture. Some of these medications may also stimulate new bone formation.

Postmenopausal women who have had a fragility fracture or who have received a bone density T-score of −2.5 or less should consider taking an osteoporosis medication.

Women with bone density T-scores from −2.0 to −2.5 may want to consider drug therapy if they have a parent with a history of hip fracture or one or more other risk factors of osteoporosis.

Talk with your doctor about whether you should begin taking osteoporosis medications, or if they think lifestyle changes alone can manage the condition.

Medications for osteoporosis

The most widely prescribed drug class is bisphosphonates. Doctors sometimes treat severe osteoporosis with:

  • Forteo (teriparatide): This medication may be prescribed for people at high risk of fracture.
  • Tymlos (abaloparatide): This medication may also be prescribed for people with a high risk of bone fracture.
  • Evenity (romosozumab): This medication is prescribed to postmenopausal women who have a high risk of bone fractures and who have used other treatments that did not work well.

Testosterone replacement therapy (TRT) may also be used to treat people with low levels of testosterone. This therapy involves applying pills, gels, or patches to your skin or receiving regular injections.

It’s important to note that the effect of TRT on bone mineral density has not yet been established. More research is needed.

Lifestyle changes for osteoporosis

Lifestyle habits that can help preserve bone health include:

  • avoiding smoking
  • minimizing alcohol intake
  • increasing physical activity and engaging in regular weight-bearing exercise, such as:
    • weightlifting
  • consuming an adequate amount of calcium
  • consuming at least 600 IU of vitamin D per day up to age 70 and 800 IU after age 70
  • treating underlying diseases that may be contributing to bone loss
  • talking with your doctor about medications that may affect bone loss, such as glucocorticoids

Researchers are continuing to examine exactly how testosterone levels affect bone mineral density.

Current evidence suggests that low testosterone is linked to an increased risk of osteoporosis and bone fracture in men, although more research is needed to confirm this link.

A common cause of osteoporosis in women is low estrogen levels.

If your testosterone levels are low, your doctor may recommend taking testosterone replacement therapy (TRT). While the benefits of TRT in reducing fracture risk have not yet been proven, it may help improve sexual function and quality of life.