New weight loss medications like Saxenda and Wegovy are helping people lose weight, but scientists are wondering if they might affect bone strength. Researchers reviewed studies from 2013 to 2024 to understand how these drugs impact bones. While animal studies showed some positive effects, human studies suggest these medications might slightly reduce bone density—similar to what happens when people lose weight through dieting. Scientists say we need more research to understand the full picture, especially to see if these drugs increase the risk of broken bones in people taking them long-term.

The Quick Take

  • What they studied: How do popular weight loss medications (GLP-1 receptor agonists like Saxenda and Wegovy) affect bone health in people with obesity?
  • Who participated: This was a review of existing research rather than a new study with participants. Scientists looked at animal studies and human research published between 2013 and 2024.
  • Key finding: Early evidence suggests these weight loss drugs may cause a small decrease in bone mineral density and increase bone breakdown, similar to what happens when people lose weight through diet alone. However, the research in humans is still limited.
  • What it means for you: If you’re taking or considering these medications, talk with your doctor about bone health. The current evidence doesn’t mean you shouldn’t use these drugs, but it suggests doctors should monitor bone health in people taking them long-term, especially those at risk for weak bones.

The Research Details

This was a literature review, meaning scientists searched through all published research on this topic from January 2013 through December 2024. They looked at both animal studies (mostly in mice and rats) and human studies to understand how GLP-1 receptor agonist medications affect bones.

The researchers examined three main areas: how these weight loss drugs affect bones directly, how regular weight loss from dieting affects bones, and how weight loss surgery affects bones. They wanted to see if there were any patterns or consistent findings across different types of studies.

By reviewing all available evidence together, the scientists could get a bigger picture of what’s known and what still needs to be studied about these medications and bone health.

A literature review is important because it brings together all the available evidence on a topic. This helps doctors and patients understand what we know and don’t know. In this case, it’s especially important because these weight loss medications are new and increasingly popular, so we need to understand all their effects—not just weight loss, but also impacts on bones and fracture risk.

This review looked at research published in English from a 12-year period, which is a reasonable timeframe. However, the authors note that human studies on this specific topic are limited, meaning we don’t have as much information from people as we do from animal studies. The review is published in a respected bone health journal, which adds credibility. Readers should know that because this is a review of existing research rather than a new study, the conclusions depend on the quality of the studies reviewed.

What the Results Show

The review found that when people lose weight through dieting or weight loss surgery, they typically lose bone mineral density (the density and strength of their bones). This happens in about 7-10% weight loss situations. The good news is that animal studies with liraglutide (Saxenda) showed some protective effects on bone quality, even when the animals lost weight.

However, when researchers looked at human studies with these medications, the picture was less clear. Early evidence suggests that GLP-1 receptor agonists may cause a modest (small) reduction in bone mineral density and increase bone turnover—meaning bones are being broken down faster than they’re being built up. This pattern is similar to what happens with regular calorie restriction.

An important finding was that in animal studies, the bone-protective effects of liraglutide only appeared at doses much higher than what doctors prescribe for people. This suggests the doses used for weight loss in humans may not provide the same bone benefits seen in the lab.

The review also examined how different weight loss methods affect bones. Bariatric surgery (weight loss surgery) causes significant bone loss, similar to or possibly greater than what happens with these medications. The researchers noted that the bone effects of these newer medications (dual and triple receptor agonists) haven’t been well studied yet, so this is an area needing more research.

This research fits with what we already know about weight loss and bones: losing weight typically leads to some bone loss, which is a known side effect of dieting and weight loss surgery. What’s new here is examining whether these specific medications have additional effects on bones beyond what weight loss alone causes. The findings suggest GLP-1 medications may have similar bone effects to regular dieting, but we need more human studies to be sure.

The biggest limitation is that there are very few human studies on this topic. Most evidence comes from animal studies, which don’t always translate directly to humans. The review also notes that we don’t yet have long-term data on fracture rates (broken bones) in people taking these medications, which is the most important health outcome. Additionally, the animal studies used higher doses than prescribed to humans, making it unclear how relevant those findings are to real-world use.

The Bottom Line

Current evidence suggests: (1) People taking GLP-1 medications should discuss bone health with their doctor, especially if they have risk factors for weak bones; (2) Doctors may want to monitor bone health in patients taking these medications long-term; (3) Maintaining adequate calcium and vitamin D intake is important; (4) Regular weight-bearing exercise helps protect bones during weight loss. Confidence level: Moderate—we have some evidence but need more human studies.

This matters most for people taking or considering Saxenda or Wegovy, especially those over 50, women past menopause, people with a family history of osteoporosis, or those taking other medications affecting bone health. People with normal bone health and short-term use may have less concern, but long-term users should be monitored. This is less relevant for people not taking these medications.

Bone changes typically develop gradually over months to years. You wouldn’t expect to notice bone loss immediately. If you’re taking these medications long-term, your doctor might recommend bone density testing (a simple, painless scan) every 1-2 years to monitor changes.

Want to Apply This Research?

  • Track weekly calcium intake (target: 1000-1200mg daily) and vitamin D intake (target: 600-800 IU daily), plus weekly weight-bearing exercise minutes (target: 150 minutes moderate activity). Log any bone or joint concerns to discuss with your doctor.
  • Users taking GLP-1 medications should: (1) Set daily reminders to meet calcium and vitamin D targets through food or supplements; (2) Schedule regular weight-bearing exercise (walking, dancing, light strength training); (3) Set a reminder to discuss bone health at their next doctor visit; (4) Track any falls or injuries to report to their healthcare provider.
  • Create a quarterly check-in reminder to review bone health metrics. If taking these medications long-term, set an annual reminder to ask your doctor about bone density screening. Track any changes in bone or joint pain, and monitor medication adherence alongside bone health markers.

This review summarizes current research on GLP-1 receptor agonist medications and bone health. The findings are preliminary, and more human studies are needed. This information is not medical advice. If you are taking or considering Saxenda, Wegovy, or similar medications, discuss bone health concerns with your doctor or healthcare provider. Do not start, stop, or change any medication without medical guidance. People with existing bone health conditions should inform their doctor before starting these medications. This content is for educational purposes only and should not replace professional medical consultation.