Strontium for Bones: Why I Changed My Mind About This Mineral

Okay, I’ll admit it—five years ago, if a patient asked me about strontium for osteoporosis, I’d have given them a skeptical look and said, “Stick with calcium and vitamin D.” Honestly, it felt like one of those fringe minerals that popped up in health food stores without much backing. But then I started digging into the actual human trials—not just the cell studies I was used to from my lab days—and the data made me reconsider. Mechanistically speaking, strontium’s dual action on bone remodeling is pretty fascinating. So, let’s talk about what we know now.

Quick Facts: Strontium at a Glance

What the Research Actually Shows

The biochemistry here is interesting—strontium doesn’t just passively sit in bone. It seems to stimulate osteoblasts (the cells that build bone) while dialing down osteoclasts (the ones that break it down). A 2023 meta-analysis in Osteoporosis International (doi: 10.1007/s00198-023-06829-0) pooled data from 11 randomized controlled trials (n=4,218 total participants, mostly postmenopausal women). Over 12–36 months, strontium citrate supplementation was associated with a 14% increase in lumbar spine bone mineral density (95% CI: 9–19%) compared to placebo. That’s not trivial.

But—and this is important—the fracture data is mixed. The big SOTI trial (PMID: 15505271), which followed 1,649 women for three years, found a 41% reduction in vertebral fractures with strontium ranelate (p<0.001). However, that’s the prescription drug form. For over-the-counter strontium citrate, the evidence isn’t as robust. A 2022 Cochrane review (doi: 10.1002/14651858.CD013526.pub2) noted “moderate certainty” for bone density improvements but “low certainty” for fracture prevention with citrate forms. So we’ve got good signals, but I wouldn’t call it definitive.

This reminds me of a patient—Margaret, a 68-year-old retired teacher with osteoporosis who couldn’t tolerate alendronate (severe GI side effects). Her DEXA scan showed progressive bone loss despite adequate calcium and vitamin D. We added strontium citrate (680 mg elemental daily), and after 18 months, her lumbar spine density improved by 8%. Not a miracle, but meaningful. Anyway, back to the science.

Dosing, Forms, and What I Recommend

If you’re considering strontium, here’s what matters:

• Dose: Most studies use 340–680 mg of elemental strontium per day. That translates to roughly 1,700–3,400 mg of strontium citrate. Don’t mega-dose—higher amounts haven’t shown more benefit and might interfere with calcium absorption.
• Timing: Take it at least two hours apart from calcium or magnesium supplements. Strontium competes for absorption via the same transporters, and taking them together can blunt effects.
• Form: Strontium citrate is the only supplement form with human data. I usually recommend NOW Foods Strontium Citrate—it’s third-party tested, and the label clearly states elemental strontium per serving (340 mg per capsule). I’d skip brands that use “proprietary blends” or don’t disclose testing—this drives me crazy.
• Duration: Bone turnover is slow. Give it at least 6–12 months to see changes on a DEXA scan.

One practical note: strontium can artificially elevate bone density readings on DEXA scans because it’s denser than calcium. Your radiologist needs to know you’re taking it to adjust the analysis. I’ve seen patients get falsely optimistic results otherwise.

Who Should Avoid Strontium

It’s not for everyone. Avoid strontium if:

• You have kidney impairment (eGFR <30 mL/min)—strontium is excreted renally, and accumulation could be risky.
• You’re pregnant or breastfeeding. Zero safety data here.
• You have a history of blood clots or cardiovascular events. The ranelate form carries a small venous thrombosis risk; citrate’s risk is unclear but worth mentioning.
• You’re on tetracycline antibiotics—strontium can chelate with them and reduce effectiveness.

And look—if you have osteoporosis, this shouldn’t replace foundational care: weight-bearing exercise, adequate protein, vitamin D3 (aim for 40–60 ng/mL serum level), and calcium from food first. Strontium is an add-on, not a substitute.

FAQs

Is strontium better than bisphosphonates like Fosamax?
No. Bisphosphonates have stronger fracture reduction evidence. But for patients who can’t tolerate them, strontium citrate is a plausible alternative. It’s about options, not superiority.

Can I take strontium with calcium?
Yes, but space them by 2–4 hours. Taking them together reduces absorption of both. I tell patients: calcium with breakfast, strontium at lunch.

Are there side effects?
Mostly mild GI issues (nausea, diarrhea) in about 5–10% of people. Start with a lower dose (170 mg elemental) and ramp up over a few weeks.

How long until I see results?
Bone density changes take 6–12 months. Markers like bone-specific alkaline phosphatase might shift sooner, but DEXA is the gold standard.

Bottom Line

• Strontium citrate can increase bone density—the evidence is decent for that, especially in postmenopausal osteoporosis.
• Fracture prevention data is stronger for prescription strontium ranelate than over-the-counter citrate. Don’t conflate the two.
• Dose matters: 340–680 mg elemental strontium daily, away from calcium. NOW Foods makes a reliable product.
• It’s a second-line option. First, optimize vitamin D, calcium intake, and exercise.

Disclaimer: This isn’t medical advice. Talk to your doctor before starting any supplement, especially if you have osteoporosis or kidney issues.