Bone tissue grows throughout your life. To keep your bones strong and healthy, special cells break down and rebuild bones. When more bone is rebuilt than is broken down, bones become dense, hard and strong.
Bone loss happens when more bone cells break down than are rebuilt. That causes bones to weaken and become more likely to fracture or break.
Having breast cancer does not cause you to develop osteopenia or osteoporosis, but some common treatments can increase your risk. Even if you have healthy bones, it’s important to do what you can to support your bone health during and after breast cancer treatment. Talk to your providers early on to find out what you can do to stop or lessen bone loss.
Early bone loss, called osteopenia, has no symptoms or pain. You might not even know you have serious bone loss, known as osteoporosis, unless you break a bone. Some people with osteoporosis also have back pain or lose height, or their posture may become stooped. The more bone loss you have, the greater the risk of bone breaks.
A bone mineral density test, or DEXA scan, can detect both osteopenia and osteoporosis. A DEXA scan is a different test than a bone scan, which you might receive as part of testing for your breast cancer diagnosis or if you have bone pain.
Breast cancer treatments that affect the way your body creates or uses estrogen may increase your risk for or speed up bone loss:
- Chemotherapy can cause early menopause or affect menstrual periods in any type of breast cancer.
- If your period comes back in less than 6 months after you finish treatment, you can reverse any bone loss you might have had with lifestyle changes or medicines. Your bones may even recover on their own.
- Hormonal therapy given to lower recurrence risk in estrogen receptor-positive breast cancer can cause bone loss.
- Ovarian surgery or suppression medicines are treatment options for some premenopausal women with ER-positive breast cancer. Surgery, or oophorectomy, removes the ovaries. These medicines prevent ovaries from making estrogen.
- Removing estrogen from your body in these ways mimics menopausal changes and puts you at risk for bone loss.
Some key factors can increase your risk for bone loss:
- Age. Aging has a major impact on bones. We build most of our bone strength and health before age 30.
- Menopause. Estrogen helps bones rebuild. After menopause, estrogen levels in your body go down, so postmenopausal women often have bone loss, regardless of cancer status.
- Exercise. Lack of exercise keeps bones from rebuilding well.
- Diet. Not getting enough calcium and vitamin D from foods or supplements weakens bones.
- Lifestyle. Smoking, drinking too much alcohol or taking illegal drugs can all cause bone loss.
- Your ethnic background and stature. Women who are thin, have a small frame and are of Caucasian or Asian descent have a higher risk of osteoporosis than Hispanic women. Hispanic women have a moderate risk of osteoporosis, and African-American women have a relatively low risk.
Men can also develop osteoporosis. No matter what your ethnic background or gender, you should discuss bone health with your doctor.
You might also be at higher risk for bone loss if your body makes too little or too much calcium or you have a family history of osteoporosis, have not had your period for a long time, or have or had an eating disorder.
Keeping a healthy lifestyle can help you protect your bones and make them stronger, even if you have bone loss.
Regular exercise helps bones become healthy and strong. The movement and muscle strength you gain from exercise helps maintain your bones and repair weakened ones. Include weight-bearing exercises and strength training such as
- brisk walking
- climbing stairs
- using resistance bands
Eating a nutritious diet is also essential. Calcium and vitamin D are vital to maintain and rebuild your bones. Here are some tips to improve your diet
- Get more calcium by eating yogurt, low-fat milk and other dairy products, fish, dark green leafy vegetables and foods with added calcium.
- Eat foods with vitamin D to help your body absorb calcium. Vitamin D is found in oily fish, cheese and fortified milk and cereal.
- Limit food and drink with caffeine because it may affect calcium levels in your body.
- Talk with your provider about how much calcium and vitamin D supplements you should be taking.
If lifestyle changes aren’t enough to treat your bone loss, you may be able to take medicines that build and strengthen bone. These include:
- Bisphosphonates – these are medicines that maintain and rebuild bones.
- As pills, you may take alendronate sodium (Fosamax), risedronate sodium (Actonel) or ibandronate sodium (Boniva)
- By vein, zoledronic acid (Reclast, Zometa)
- Bisphosphonates may cause a very rare side effect of exposed bone in the jaw that does not heal, called osteonecrosis of the jaw or ONJ. This side effect occurs in fewer than 1 in 1,000 women who take zoledronic acid. The risk is higher if you have metastatic breast cancer to your bone and need to take bisphosphonates for a long time as part of your treatment. See your dentist before you start taking a bisphosphonate. Once you start taking them, make sure to talk to your oncology team before having invasive dental procedures such as tooth extractions.
- Raloxifene (Evista) is a pill to prevent and treat osteoporosis in postmenopausal women.
- Denosumab (Prolia) is a type of medicine called a RANK ligand inhibitor that helps to grow bone mass in women at risk for fractures because of aromatase inhibitor treatment. It is given by injection once every 6 months.
- Calcitonin nasal spray is derived from salmon and helps make bone in postmenopausal women with osteoporosis.
Other general tips to help keep your bones strong:
- get help to stop smoking
- avoid drinking too much alcohol
- do not take illegal drugs
If you have metastatic breast cancer, learn more about ongoing treatment and bone loss.