GLP-1 Bone Loss: What the New AAOS Research Actually Means for You

Researchers just dropped something at this year's American Academy of Orthopaedic Surgeons annual meeting that's going to be all over health news this week. I want to get ahead of it before the panic takes hold.

Here's the short version: Two new studies show that GLP-1 medications, including semaglutide (Ozempic, Wegovy, Mounjaro), are linked to increased long-term risk of osteoporosis, gout, and osteomalacia in people who've been on them for five years or more. The same conference also showed that GLP-1 users have better short-term outcomes after common surgeries.

That's not a typo. Better in the short run. Worse bone health in the long run. And yes, that matters.

I'm going to break down what the data actually shows, explain the paradox that most headlines will miss, and tell you exactly what I'm already doing with my patients to get ahead of this.

New data means new strategies. Not panic. Here's what you need to add to your plan.

What the Research Actually Shows

The main study tracked over 146,000 adults with obesity and Type 2 diabetes for five years. Researchers matched GLP-1 users against controls who weren't on the medications, balancing the groups for age, sex, BMI, A1c, and other health conditions. The final matched cohort was 73,483 patients.

After five years, GLP-1 users showed:

• Osteoporosis: 4.1% of GLP-1 users developed it vs. 3.2% of controls. That's roughly a 30% increased risk.
• Gout: 7.4% of GLP-1 users vs. 6.6% of controls, about a 12% increased risk.
• Osteomalacia (softening of the bones): Rare overall, but occurring roughly twice as often in GLP-1 users.

All of those differences were statistically significant.

Dr. John Horneff, an orthopedic surgery professor at the University of Pennsylvania, said he started looking into this after noticing patients showing up with serious tendon tears after minor injuries. That pushed his team to look at how GLP-1s might affect bone and connective tissue more broadly.

"People are taking these medications, and obviously there's a tremendous amount of upside," Horneff said. "But with that, they start to decrease their intake of food and nutrients."

That sentence is the crux of it. I'll come back to it.

A few honest caveats before anyone spirals: this study was observational. It can't prove the medications caused these conditions. Researchers also didn't have data on patients' diet, exercise habits, or supplement use. Those are real gaps.

But the findings line up with other research. A study published last month in the Journal of Clinical Endocrinology and Metabolism linked GLP-1 drugs to higher fracture risk in older adults with Type 2 diabetes. This isn't one outlier study. There's a pattern building.

The Paradox Worth Understanding

Here's the part that gets lost in most coverage, and it's the piece that actually makes this story more nuanced, not more alarming.

The same AAOS meeting presented a second study showing GLP-1 use is associated with improved short-term surgical outcomes across 10 common orthopedic procedures. Lower rates of postoperative emergency visits. Lower surgical site infection rates for total knee and hip replacements. Better recovery, not worse.

So the same class of medications, at the same conference, showing opposite findings depending on the timeframe you're looking at.

Short-term: better outcomes after surgery. Long-term: higher risk of bone and joint problems.

That's not a contradiction. It's a timeline issue. And it tells us something important: the benefits of GLP-1s in the short run don't automatically protect your musculoskeletal health years down the road.

Weight loss from GLP-1s can reduce stress on joints before surgery, lower inflammation, and improve metabolic markers that affect healing. All real benefits. But if you're losing significant weight rapidly and not paying attention to nutrition, your bones may be paying a price that shows up five years later, not five months later.

Both things can be true at the same time.

Why This Is Probably Happening

No one's saying definitively what's driving the bone and joint risks. But the most clinically plausible explanation is straightforward: nutrient insufficiency.

GLP-1 medications work in part by significantly suppressing appetite. When you eat substantially less, you take in less calcium, less vitamin D, less protein. Those three nutrients are the structural foundation of bone health.

"Weight loss does cause bone loss," said Dr. Clifford Rosen from Tufts University, who has been studying GLP-1s and bone health. The question his research is examining is whether the bone changes seen with GLP-1s are a normal skeletal adaptation, or whether bone is being lost faster than expected.

That distinction matters clinically. Gradual skeletal remodeling is different from accelerated bone loss.

The FDA already notes in semaglutide's prescribing information that it might increase fracture risk in older adults and women. That warning predates this AAOS data. Now there's more evidence pointing the same direction.

Here's the part that concerns me most as an RD: most GLP-1 users aren't working with a dietitian who's actively monitoring their nutrient intake. The appetite suppression can make it easy to undereat without realizing it. You feel full on smaller amounts, you eat less, and you slowly develop gaps in calcium, vitamin D, and protein intake without any obvious symptoms until something breaks, sometimes literally.

Why This Matters If You're on a GLP-1

Most people on GLP-1 medications are women in their 30s to 50s. Many are already moving toward perimenopause, when estrogen decline naturally accelerates bone loss. A 30% increased risk of osteoporosis on top of an already elevated baseline risk is a clinically meaningful number.

Gout might sound less serious, but uric acid buildup causes significant joint pain and can be debilitating. Osteomalacia, the bone softening condition, causes bone pain, muscle weakness, and stress fractures that often get misattributed to something else until they're hard to miss.

The five-year timeframe of this research is also critical context. We're just now getting five- and ten-year follow-up data on GLP-1 users. Most people currently on these medications started within the last two to three years. That means we're at the beginning of understanding the long-term picture, not anywhere near the end.

That's not a reason to stop medication. It's a reason to start paying attention now.

What I'm Already Doing in Practice

I'll be direct about this: I'm not surprised by this research. It's consistent with what I see clinically, and it's why bone health screening is already part of how I work with GLP-1 patients.

Bone health isn't new territory for dietitians. We've tracked calcium and vitamin D for decades in other contexts. What this AAOS data does is confirm that GLP-1 nutrition counseling needs to include this conversation routinely, because most patients aren't having it with their prescribers.

When I sit down with a GLP-1 patient, I'm already asking about:

Calcium intake. Adults need 1,000 to 1,200mg daily. Most GLP-1 users eating significantly less aren't getting close to that through food alone. Dairy, fortified plant milks, leafy greens, canned fish with bones, almonds. These need to be intentional choices, not accidental ones. And the timing matters too: the body absorbs calcium better in smaller doses spread throughout the day, not one large supplement at night.

Vitamin D status. Most US adults are deficient. GLP-1 users eating less and potentially spending less time outdoors are especially at risk. I order labs and I recommend supplementation when levels are low. The target is 40-60 ng/mL, not just "technically in range."

Protein intake. This one isn't negotiable. Protein isn't just about muscle. Adequate protein supports bone matrix formation. I'm targeting 1.2 to 1.6 grams per kilogram of body weight daily. That's a number I calculate with each patient, not a vague "eat more protein" suggestion. Use our protein calculator to estimate your baseline target, and use GLP-1 meal plans to make that target practical day to day.

Weight-bearing exercise. This is the bone health intervention that doesn't come in a bottle. Walking, resistance training, anything that puts mechanical stress on bones signals them to stay dense. As I always say: muscle preservation is metabolism preservation. Turns out it's bone preservation too. Even ten-minute walks count. The question is whether it's happening consistently.

None of this is novel science. But assembling it specifically in the context of GLP-1 therapy is a conversation most patients aren't getting. That's the gap.

What to Actually Do Starting Now

If you're on a GLP-1 medication, here's where I'd start:

1. Get baseline bone density testing if you're at risk. Especially if you're a woman over 40, postmenopausal, or have a family history of osteoporosis. A DEXA scan gives you a starting point. You can't track change without a baseline.

2. Calculate your actual calcium intake. Not an estimate. Three days of tracking what you're actually eating. Most GLP-1 users are falling short. If you're consistently under 1,000mg, either increase calcium-rich foods intentionally or discuss supplementation with your doctor.

3. Get your vitamin D level tested. Ask for it at your next appointment. Many prescribers don't order it unless you ask. You need the number, not a guess.

4. Treat protein as a floor, not a goal. The target is non-negotiable, especially when your appetite is suppressed and you're eating less overall. Plan your protein sources before each day starts. Greek yogurt, eggs, cottage cheese, lean meat, legumes. Every meal is an opportunity you can't afford to skip.

5. Add weight-bearing movement. You don't need a gym or a structured program. You need gravity and your body weight doing something regularly. Walking counts. Resistance bands count. Bodyweight squats in your living room count. This is one of the most powerful things you can do for long-term bone health, and it's free.

6. Bring this to your prescriber. Your GLP-1 prescriber needs to know about this research. Ask whether bone density monitoring should be part of your long-term plan. Ask about vitamin D testing. Ask about fracture risk. Proactive conversations are always easier than reactive ones.

The Bottom Line

GLP-1 medications are genuinely helping people, and today's data from AAOS doesn't change that. The improved surgical outcomes at the same meeting are real. The cardiometabolic benefits are real. People are improving their health on these medications every day.

But the five-year bone data is telling us something that responsible GLP-1 prescribing and support can't ignore: the medication needs a nutritional strategy running alongside it. Appetite suppression changes what you eat. What you eat builds or depletes your bones. That connection isn't complicated. It just requires attention.

This is what dietitians are for. Not telling you what not to eat. Figuring out what your bones need when your appetite isn't reminding you to eat enough.

If you're on a GLP-1 and you haven't had a conversation about calcium, vitamin D, protein, and weight-bearing exercise, that conversation is overdue. Not because something's already wrong. Because prevention is always easier than repair.

On a GLP-1 and want to make sure your nutrition is actually protecting your health long-term? The GLP-1 Sidekick app tracks protein, helps you build high-nutrient meal plans, and was built by a registered dietitian who works with GLP-1 patients every day. Download it free.

Frequently Asked Questions

Do GLP-1 medications cause bone loss?

New research from the 2026 AAOS annual meeting shows GLP-1 users have about a 30% higher risk of osteoporosis over five years compared to matched nonusers. The study was observational and can't prove causation, and researchers didn't have data on participants' diet or supplement use. The most plausible mechanism is reduced calcium, vitamin D, and protein intake from appetite suppression, not a direct drug effect on bone tissue.

What nutrients protect bone health on GLP-1 medications?

Calcium (1,000 to 1,200mg daily), vitamin D (target blood levels of 40-60 ng/mL), and protein (1.2 to 1.6g per kilogram of body weight) are the three most critical. Weight-bearing exercise is equally important and often the piece most people overlook.

Should I stop my GLP-1 medication because of this research?

No. Talk to your prescriber before making any changes. The benefits of GLP-1 medications are substantial and documented. The right response to this data is adding bone health monitoring and optimizing nutrition, not stopping medication without medical guidance. Work with a registered dietitian if you haven't already.

How often should bone density be checked while on GLP-1 medications?

Clinical guidelines haven't established a specific protocol for GLP-1 users yet. Starting with a baseline DEXA scan gives you a reference point. The frequency of follow-up depends on your age, menopausal status, and other individual risk factors. Discuss this with your prescriber based on your full health picture.

Is the bone loss risk the same for Ozempic, Wegovy, and Mounjaro?

The primary study included patients on various GLP-1 medications including semaglutide (Ozempic, Wegovy) and liraglutide. Tirzepatide (Mounjaro, Zepbound) wasn't specifically isolated in this research. The mechanism driving bone risk appears related to reduced food and nutrient intake, which would apply to any GLP-1 or GIP/GLP-1 medication that significantly suppresses appetite.

Dan Chase is a Registered Dietitian specializing in nutrition for people on GLP-1 medications. For personalized meal planning and support, visit chase-wellness.com.

Sources

1. Horneff JG, Wajahath M, et al. "GLP Receptor Agonist Use is Associated with Increased Risk of Osteoporosis, Gout and Osteomalacia in Adults with Type 2 Diabetes and Obesity." Presented at the 2026 AAOS Annual Meeting, New Orleans, LA.
2. Haque H, et al. "Rising Use of GLP-1 Agonists Across Common Orthopaedic Procedures and Their Association with Improved Postoperative Outcomes." Presented at the 2026 AAOS Annual Meeting, New Orleans, LA.
3. Journal of Clinical Endocrinology and Metabolism, February 2026. GLP-1 use and fracture risk in adults with Type 2 diabetes.