Hyperthyroidism and Osteoporosis: What Is the Relationship?

Because of how thyroid hormone impacts bone turnover (bone breakdown and new bone growth), people with hyperthyroidism have an increased risk of getting osteoporosis and more severe osteoporotic disease.

Read on to learn more about how hyperthyroidism affects bone loss and how you can manage both conditions simultaneously.

Connection Between Hyperthyroidism and Osteoporosis

Elevated thyroid hormone activity (hyperthyroidism) increases your risk of osteoporosis, a condition that causes a loss in bone mass and increases the risk of fractures. This is also true for underlying conditions that cause hyperthyroidism, including the immune system condition Graves' disease, thyroid adenoma (a benign thyroid cyst), and others. 

Elevated levels of thyroid hormone seem to increase the rates at which bone is destroyed and decrease the rates at which it is rebuilt. Not surprisingly, this can lead to the reduced bone mass seen in osteoporosis.  

Scientists aren’t exactly sure why this is but believe that thyroid hormone released by your thyroid gland may affect the cells involved in building and breaking down bone, called osteoblasts and osteoclasts. 

Low levels of another hormone, called thyroid stimulating hormone (TSH), also seem to increase bone breakdown. Since TSH is usually low in people with hyperthyroidism, it may also account for increased osteoporosis risk.

Risks

Many studies have shown that people with untreated hyperthyroidism have significantly decreased bone density. Moreover, they have an increased risk of breaking bones, such as a fracture to the hip. This risk increases with age, just as it does for people with osteoporosis without hyperthyroidism.

Severe hyperthyroidism poses a more significant risk of osteoporosis than mild hyperthyroidism. But even people with subclinical hyperthyroidism (normal thyroid hormone levels but abnormally low TSH) may have an increased risk.

However, your risk of osteoporosis from hyperthyroidism varies and depends on other risk factors you may have for osteoporosis. For example, a young person assigned male at birth with hyperthyroidism but no other risk factors for osteoporosis is unlikely to have issues. 

However, incidence increases in people with other factors that contribute to osteoporosis, such as people of older age, individuals assigned female at birth, and people with a history of smoking, your risk becomes greater. Hyperthyroidism is just one potential risk factor for osteoporosis that you and your healthcare provider should consider.

Additionally, hyperthyroidism might make your osteoporosis more severe.

Treatment and Management of Hyperthyroidism and Osteoporosis

The good news is that treating hyperthyroidism may bring your rate of bone loss back to your baseline, even if you don’t use any other treatments for osteoporosis. Once your hyperthyroidism is treated and under control, your osteoporosis risk reduces.

However, depending on the severity of the condition(s), the underlying cause(s), age, and other health conditions, you may also need to treat osteoporosis. This may include medication to help strengthen bones. Speak to your healthcare provider to determine a treatment plan.

Monitoring

In some cases, having hyperthyroidism might mean you'll need additional testing and monitory for osteoporosis. For instance, because hyperthyroidism increases your overall risk of osteoporosis, you might need to get bone mineral tests at an earlier age compared to people without hyperthyroidism. 

Most women without risk factors for osteoporosis do not need bone mineral density testing until age 65, whereas people with hyperthyroidism often require testing at an earlier age.

Prevention

If you have hyperthyroidism or have had it in the past, you can take steps to prevent osteoporosis in the future, even if you aren’t at risk right now. Building your bone mass at a younger age can help prevent issues as you get older. The following can help you maintain your bone mass as osteoporosis becomes a more serious risk.

• Get enough calcium and vitamin D in your diet. Ask your healthcare provider if taking a supplement makes sense.
• Stay active with weight-bearing exercises like walking, jogging, and strength training.
• Don’t smoke.
• Limit your use of alcohol. 

Summary

Those with hyperthyroidism tend to have a faster bone breakdown and slower bone regrowth than those without the condition. Over time, this increases the risk for osteoporosis, especially in older individuals who are already at a higher risk.

Hyperthyroidism doesn't guarantee you'll get osteoporosis; it's just one of several factors that can increase your risk.

Treating hyperthyroidism itself can help you lower your risk of osteoporosis. But you can make other lifestyle choices to help prevent osteoporosis, too, like getting enough calcium and vitamin D and limiting your intake of alcohol.