Breast Cancer and Osteoporosis: What is the Connection?

Medically Reviewed By: Philip D. Poorvu, MD

What is osteoporosis?

Osteoporosis is a condition that thins and weakens the bones in a way that makes them more likely to fracture, especially the bones in the hip, spine, and wrist.

Are there any risk factors for osteoporosis?

Osteoporosis can occur to anyone, but it is more common in older women. Risk factors include:

  • Getting older
  • Being small and thin
  • Having a family history of osteoporosis
  • Taking certain medicines (prednisone for instance)
  • Lack of physical activity
  • Smoking cigarettes
  • Heavy alcohol use
  • Not getting enough calcium and vitamin D in your diet

How do you know if you have osteoporosis?

People who have osteoporosis usually have no symptoms from it and may not know that they have it. Often, medical professionals recommend bone density testing to screen for osteoporosis. Sometimes, a bone density test may be done after a fracture to help understand why the fracture occurred and how to lower the risk of future fractures.

A bone density scan, also called a DEXA scan, measures calcium and other minerals in your bones. This low-dose X-ray test helps show the overall strength and thickness of your bones.

Bone density results are often given in the form of a T score, a measurement that compares your bone density measurement with the bone density of a healthy 30-year-old. A low T score indicate possible bone loss.

Your results may show one of the following:

  • A T score of -1.0 or higher, which is considered normal bone density.
  • A T score between -1.0 and -2.5, which indicates you may have low bone density (osteopenia) and may be at risk for developing osteoporosis.
  • A T score of -2.5 or less, which indicates that you have osteoporosis.

If your results show you have low bone density, your health care provider will recommend steps to prevent further bone loss.

How is osteoporosis connected with breast cancer?

Breast cancer treatments may increase the risk for bone loss and fractures. Reasons for this may include:

  • Loss of ovarian function/menopause: Reduced estrogen, either through menopause or medications that reduce estrogen, can cause bone loss because estrogen is protective for bones.
  • Reduced levels of hormones: By receiving hormone therapy, which blocks hormones that spur certain cancers to grow, some patients may have reduced levels of estrogen, which has a protective effect on the bone.

How can a person prevent further bone loss?

Several strategies can be used to reduce one’s risk for osteoporosis or to reduce the risk of bone fractures for those who have osteoporosis, including:

  • Nutrition: A well-balanced diet rich in calcium and vitamin D is important. Patients with osteoporosis should take vitamin D supplements and make sure to get enough vitamin D through diet.
  • Exercise: The best activities for your bones are weight-bearing and resistance exercises. Weight-bearing exercises include walking, climbing stairs, and dancing. Resistance exercises — such as lifting weights — can also strengthen bones.
  • Healthy lifestyle: A healthy lifestyle involves quitting smoking if you are a smoker, or reducing alcohol consumption. Smoking is bad for the bones as well as the heart and lungs. Women who smoke also tend to go through menopause earlier, resulting in earlier reduction in levels of the bone-preserving hormone estrogen and triggering earlier bone loss. High alcohol consumption can lead to a slightly higher risk of breast cancer in women and has an overall negative effect on bone health.
  • Medications: Some medications, including bisphosphonates or denosumab, can improve bone density and reduce fractures.

About the Medical Reviewer

Philip D. Poorvu, MD

Dr. Poorvu received his medical degree from the University of Pennsylvania in 2012 and went on to complete his residency in internal medicine at the Brigham and Women's Hospital. He is a medical oncologist in the breast Oncology Center and has a particular interest in the care of young women with breast cancer and breast cancer survivorship. His research seeks to better understand the impact of cancer treatments on fertility and a number of other survivorship issues. Dr. Poorvu's research is also focused on the use of genomic risk prediction assays and predictive biomarkers to help guide the management of breast cancer patients.