Fracture Prevention: How Calcium, Vitamin D, and Bone-Building Medications Really Work

Every year, more than 2 million fractures happen in the U.S. because of weak bones. Most of these aren’t from car crashes or sports injuries-they’re from simple falls, like stepping off a curb or slipping in the bathroom. If you’re over 50, especially if you’re a woman, your risk goes up fast. The good news? You don’t have to wait for a break to happen. The right mix of calcium, vitamin D, and bone-building medications can make a real difference-but only if you use them the right way.

Calcium and Vitamin D: The Basics That Don’t Always Work

You’ve heard it a thousand times: “Take calcium and vitamin D for strong bones.” It sounds simple. But here’s the truth: taking low doses of both won’t stop fractures. The US Preventive Services Task Force looked at data from nearly 40,000 people and found that if you’re taking 400 IU of vitamin D or less than 1,000 mg of calcium daily, you’re not reducing your fracture risk at all. That’s not a myth-it’s science.

So what does work? Studies show that when you combine 800-1,000 IU of vitamin D3 with 1,000-1,200 mg of calcium every day, you cut your risk of hip fractures by about 16%. That’s not a magic number-it’s the minimum effective dose. The landmark 1992 study from France followed nursing home residents with severe vitamin D deficiency. Their average level was just 12.3 ng/mL. After adding 800 IU of vitamin D and 1,200 mg of calcium daily, hip fractures dropped by 43%. That’s huge.

But here’s the catch: if you’re already getting enough vitamin D from sunlight or food, or if you’re living independently and not severely deficient, the benefit shrinks. The RECORD trial in the UK found no benefit in community-dwelling older adults with baseline levels around 18.5 ng/mL. That means supplementation isn’t one-size-fits-all. If your blood level is below 20 ng/mL, you likely need it. If it’s above 30 ng/mL, extra pills won’t help-and might even hurt.

The Hidden Risks of Too Much Calcium

Calcium isn’t harmless. The Women’s Health Initiative found that women taking 1,000 mg of calcium daily had a 17% higher risk of kidney stones. That’s not rare-it’s common enough to matter. And it doesn’t stop there. High-dose calcium (over 1,000 mg/day) was linked to a 17% increased risk of heart attacks in the same study. The FDA flagged this in 2021. Why? When you flood your system with calcium from pills, your body doesn’t always know how to handle it. Instead of going straight to your bones, some of it ends up in your arteries.

Food sources of calcium are safer. One cup of yogurt has about 300 mg. A glass of fortified milk? Another 300. Half a cup of cooked kale? Around 100 mg. You don’t need a 1,200 mg supplement if you’re eating dairy, leafy greens, tofu, or canned salmon with bones. The real problem? Most people don’t track their intake. They take a pill thinking it’s insurance, then eat cheese on their sandwich and drink a glass of milk-and suddenly they’re hitting 2,000 mg. That’s not protection. That’s overkill.

Bone-Building Medications: When Supplements Aren’t Enough

If you’ve already broken a bone from a minor fall, or if your bone density scan shows osteoporosis, supplements alone won’t cut it. That’s where medications come in. They don’t just slow bone loss-they rebuild it.

Bisphosphonates like alendronate (Fosamax) and zoledronic acid (Reclast) are the most common. In the Fracture Intervention Trial, alendronate cut vertebral fractures by 44%. Zoledronic acid, given as a yearly IV drip, reduced hip fractures by 41% over 18 months. These drugs work by blocking the cells that break down bone. Simple. Effective. But they come with side effects. About 68% of people on oral bisphosphonates report stomach upset. One in five stop taking them within a year because of it.

Then there’s denosumab (Prolia), a monthly injection that works differently. It targets a protein called RANKL, which tells bone cells to break down. It’s powerful-reducing spine fractures by 68% in trials. But if you miss a dose, your bone loss can rebound fast. You can’t just stop it cold. You need to switch to another medication.

Newer drugs like teriparatide (Forteo) and romosozumab (Evenity) actually build new bone. Teriparatide is a daily injection that mimics parathyroid hormone. In trials, it cut spine fractures by 65%. Romosozumab, given as a monthly shot, builds bone faster than any other drug. One study showed a 73% greater reduction in new spine fractures when used before switching to an antiresorptive like denosumab. But these are expensive. And they’re not for everyone. Teriparatide is limited to two years of use. Romosozumab carries a black box warning for heart attack risk.

Who Really Needs These Medications?

Not everyone with low bone density needs a prescription. The key is figuring out your real risk. That’s where the FRAX® tool comes in. It’s free, online, and used by doctors worldwide. You plug in your age, sex, weight, whether you’ve had a prior fracture, if you smoke, if you drink alcohol, and your bone density score. Then it calculates your 10-year chance of a major fracture.

In the U.S., if your risk is over 20%, treatment is recommended. In the UK, it’s 15%. If you’re 72, 5’2”, weigh 110 pounds, had a wrist fracture last year, and your bone density is -3.0, you’re a clear candidate. If you’re 60, healthy, active, and your score is -1.8? You’re probably fine with lifestyle changes and maybe vitamin D if you’re deficient.

And here’s something most people don’t realize: you need a dental checkup before starting bisphosphonates or denosumab. These drugs can rarely cause jawbone death (osteonecrosis). It’s extremely rare-less than 1 in 10,000-but it’s preventable. Get your cavities filled, your gums checked, and avoid extractions while on these meds.

Why People Stop Taking Their Medications

Even the best drug won’t help if you don’t take it. Studies show more than half of people stop bisphosphonates within a year. Why? Side effects. Confusion. Cost. Belief that “it’s just a supplement.”

One woman in Sydney told her doctor she stopped alendronate because she couldn’t remember to take it on an empty stomach every morning. She’d eat breakfast, feel fine, and think, “I’ll just take it later.” But that’s how it fails. Bisphosphonates need to be taken first thing in the morning, with a full glass of water, and you can’t eat or drink anything else for 30 minutes. If you mess up the timing, you absorb almost nothing.

IV zoledronic acid solves that problem. One 15-minute infusion a year. No daily pills. No stomach upset. But it can cause flu-like symptoms for a day or two. Some people hate that. Others love it because it’s one-and-done.

And then there’s the psychological barrier. Many think, “If I don’t feel pain, I don’t need it.” But osteoporosis doesn’t hurt until you break a bone. That’s why doctors need to explain it like this: “This isn’t medicine for pain. It’s insurance against disaster.”

What You Should Do Right Now

Here’s a simple plan if you’re over 50:

1. Ask your doctor for a bone density test (DEXA scan). Don’t wait for a fracture.
2. Get your vitamin D level checked. If it’s under 30 ng/mL, you likely need supplementation.
3. Don’t take more than 1,200 mg of calcium daily from all sources combined-food and pills.
4. If you’ve had a fracture or your FRAX score is high, talk about bisphosphonates, denosumab, or newer agents. Don’t settle for supplements alone.
5. If you’re on medication, stick with it. Set phone reminders. Ask for the injection option if pills are too hard.
6. Move your body. Weight-bearing exercise (walking, lifting weights) is just as important as any pill.

Fracture prevention isn’t about taking more supplements. It’s about taking the right ones, at the right dose, for the right person. It’s about knowing your risk. It’s about not giving up when the first pill makes your stomach upset. It’s about realizing that a broken hip at 70 isn’t just a bad day-it’s a life-altering event. And with the right approach, you can avoid it.