Menopause and Bone Loss: What's Happening and What You Can Do About It
You can't feel bone loss happening. You can feel a hot flash. You notice when you're not sleeping well. You may even notice changes in your muscles and how your body responds to exercise.
Your bones are different. Bone loss happens quietly, which is one reason it can be easy to ignore until a bone density scan shows osteopenia or osteoporosis, or until you have a fracture. And menopause is an especially important time to pay attention.
Bone loss accelerates around the menopause transition, often before your final menstrual period. The good news is that there is a lot you can do to protect your bones. The first step is understanding when bone loss happens, whether you're at increased risk, and what you can actually do about it.
Why Does Menopause Affect Your Bones?
Your bones are living tissue. Throughout your life, old bone is constantly being removed and replaced with new bone. Two types of cells do most of this work. Osteoclasts break down old bone, while osteoblasts build new bone. When you're younger, these processes are generally balanced.
Estrogen helps regulate this process. As estrogen becomes lower and more variable during the menopause transition, bone resorption increases, so you begin losing bone faster than you replace it. Estrogen is an important part of the story, although age and other hormonal and biological changes also contribute.
When Does Bone Loss Happen During Menopause?
Most of us don't think much about bone density in our 20s and 30s. That's when we're building toward our peak bone mass. After that, bone density is influenced by genetics, body size, nutrition, physical activity, hormones, medications, medical conditions, and aging.
Around menopause, bone loss speeds up considerably. The most rapid loss occurs during the menopause transition, beginning before your final menstrual period and continuing for the first few years after it. Bone loss then slows again, although it continues at a slower rate as you age. That's why you shouldn't wait until you're officially postmenopausal to start paying attention.
Who Is More Likely to Lose Bone?
There isn't one number or one characteristic that tells us whether you're going to develop osteoporosis or experience a debilitating fracture. Some of your risk comes from things you can't change, including your age, genetics, family history, and the amount of bone you built when you were younger. Other risk factors are ones we can actually do something about. Body composition, nutrition, and weight stability all play a role, as does your weight relative to your height. Behavior matters too: smoking, high alcohol intake, and low physical activity all increase bone loss or fracture risk, along with early menopause or primary ovarian insufficiency (POI), certain medications such as long-term glucocorticoids, and medical conditions that affect bone or interfere with nutrient absorption.
When Weight Loss and Menopause Overlap
This is becoming an increasingly important conversation.
Menopause is already a time when it becomes harder to maintain muscle, and bone loss accelerates around the menopause transition. At the same time, many women are trying to lose weight, sometimes with the help of a GLP-1 medication.
GLP-1 medications can be very effective when they're medically appropriate. But significant weight loss can include some loss of lean mass, and eating substantially less can make it harder to get enough protein, calcium, vitamin D, and other nutrients. Put those together with the hormonal changes of menopause, and you've got a situation where losing both muscle and bone deserves some attention.
The effects of GLP-1 medications on bone are still uncertain, but we are starting to get more data. Some studies suggest that people taking GLP-1 medications may lose more bone density or be more likely to receive a diagnosis of osteoporosis. We still have a lot to learn about how much of this is related to the medication itself, the amount and speed of weight loss, changes in muscle mass, nutrition, or the underlying health of the people taking these medications. Importantly, we also can't predict whether those changes in bone translate into more fractures in everyday clinical practice: studies of fracture risk have reported mixed results, with some showing similar or lower risk and others showing higher risk in particular groups.
Bottom line: If you're losing a significant amount of weight during menopause, protecting your bones should be part of the plan. Make sure you're getting adequate protein and other nutrients, keep resistance training in the picture, and include weight-bearing activity.
If you're considering or taking a GLP-1 medication, see GLP-1s and Menopause: Separating Evidence from Hype for a more detailed discussion of the benefits, limitations, and menopause-specific considerations.
Do I Need a Bone Density Scan?
The primary test we use to measure bone density is a DXA scan, sometimes called a DEXA. It measures bone mineral density, usually at the hip and spine.
Your result is reported as a "T-score". The T-score is a measurement of bone density compared to a healthy young adult of the same sex:
-1.0 or higher: normal bone density
Between -1.0 and -2.5: osteopenia
-2.5 or lower: osteoporosis
But your T-score is only one piece of the picture. Bone density and fracture risk are related, but they aren't the same thing. Age, previous fractures, medications, medical conditions, and other factors can affect your actual risk of breaking a bone.
When should you have a DXA?
In the United States, the U.S. Preventive Services Task Force recommends women begin screening at age 65. For postmenopausal women younger than 65, the recommendation is to assess risk first and then screen women whose risk is increased. Some women will need a DXA well before 65. Others can reasonably wait. The point of risk assessment is figuring out which group you're in rather than defaulting to either extreme.
If you have risk factors for osteoporosis, including low body weight defined as BMI less than 20 kg/m², family history of osteoporosis, experienced early menopause, are taking a medication or have a medical condition that affects bone, or have a history of a fracture from a fall from standing height or less, your clinician may recommend evaluating your bone health earlier. A fracture like this can indicate increased fracture risk even when your T-score isn't in the osteoporosis range.
FRAX is one tool that we use to determine when to treat bone loss. FRAX estimates your 10-year probability of having a major osteoporotic fracture or hip fracture. It combines information about your age, weight, medical history, fracture history, and other risk factors to estimate your 10-year probability of having a major fracture. It can also incorporate your DXA result when one is available.
I Have Osteopenia. What Does That Mean?
This is one of the most common things I hear after a DXA: "But I exercise. I eat well. I've been healthy my whole life. How can I have osteopenia?" And honestly, I understand why you're frustrated.
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