Supplement analysis backed by scientific evidence · PT · ES · DE · FR

← All supplements
Limited evidenceWomen's health

Strontium

Almost everything people cite for strontium comes from strontium ranelate — a prescription drug that reduced fractures but was restricted across Europe for heart attack risk and is no longer marketed. The strontium citrate sold as a supplement has no fracture trials at all, and it inflates DXA bone density readings, making its apparent benefit look bigger than it is.

View on iHerb Ships to 180+ countries · welcome discount for new customers

What the science says

  • Vertebral fracture reduction (strontium ranelate) Strong evidence

    In the SOTI trial, 1,649 postmenopausal women with osteoporosis took 2 g/day strontium ranelate or placebo; new vertebral fractures fell by about 41% over 3 years (RR ~0.59). The TROPOS trial in 5,091 women found a ~16% reduction in all non-vertebral fractures, with a hip fracture benefit only in a high-risk post hoc subgroup. This is drug-grade evidence for a specific salt at a specific dose.

  • Strontium citrate supplements Limited evidence

    The over-the-counter form is strontium citrate, not ranelate. No randomized fracture trial has ever been run on strontium citrate in humans; supplement doses (typically 680 mg elemental strontium) are extrapolated from the ranelate trials on the assumption that only the strontium matters. That assumption is untested.

  • Bone density gains are partly an artifact Moderate evidence

    Strontium's atomic number is much higher than calcium's, so strontium deposited in bone over-attenuates X-rays and inflates DXA-measured BMD. Correction studies indicate roughly half of the apparent BMD gain on strontium is measurement artifact rather than new bone. Reported "14% BMD increase" figures should be discounted accordingly.

  • Cardiovascular and hypersensitivity risk Moderate evidence

    Pooled trial data linked strontium ranelate to an excess of myocardial infarction, prompting the European Medicines Agency in 2014 to restrict it to severe osteoporosis with no cardiovascular risk factors; the product was subsequently withdrawn commercially. Venous thromboembolism and rare DRESS syndrome (drug rash with eosinophilia and systemic symptoms), which can be fatal, are also documented.

Dosage & safety

Studied doseThe studied prescription regimen was strontium ranelate 2 g/day (equivalent to ~680 mg elemental strontium) taken at bedtime, at least 2 hours away from food, calcium or dairy, which sharply reduce absorption. Supplement strontium citrate is sold at 680 mg elemental strontium per day on the same reasoning, without direct evidence. Adequate calcium and vitamin D were provided in all the trials.
SafetySerious signals, not theoretical ones: increased myocardial infarction risk (basis of the EMA restriction), venous thromboembolism, seizures, and DRESS syndrome. Contraindicated in ischemic heart disease, peripheral arterial disease, cerebrovascular disease, uncontrolled hypertension, and current or prior VTE. Strontium ranelate was never approved in the United States and has been withdrawn from the European market; strontium citrate is sold as a supplement in the US with no equivalent safety review. It competes with calcium for absorption, reduces absorption of tetracyclines and quinolones, and permanently distorts DXA scans — tell your physician before any bone density test. Not appropriate as a casual bone supplement.

How to take it

TimingAt bedtime, which is how the trials dosed it.
With food?On an empty stomach, at least 2 hours after food, calcium or dairy — all of them sharply reduce absorption.
Worth knowingStrontium ranelate was restricted in Europe and never approved in the US over heart attack risk; the citrate sold as a supplement got no equivalent safety review, and it permanently distorts bone density scans.

Interactions

With medications

  • tetracycline and fluoroquinolone antibiotics

    Strontium chelates these antibiotics and reduces their absorption. take the antibiotic at least 2 hours before or 4-6 hours after

  • calcium-containing antacids and supplements

    Calcium and strontium compete for the same absorption pathway, sharply reducing strontium uptake. separate by at least 2 hours

  • DXA bone density scanning

    Strontium is much denser than calcium and inflates the measured bone mineral density, making results look better than they are. tell whoever orders or reports your DXA scan that you take strontium

With other supplements

  • calcium

    Direct absorption competition in both directions. take strontium at bedtime and calcium with meals, at least 2 hours apart

Well-established interactions only — this is not a complete list. Always tell your doctor and pharmacist what you take.

Frequently asked questions

Does strontium prevent fractures?

Only strontium ranelate, a prescription drug, has strong fracture evidence: it cut new vertebral fractures by about 41% in the SOTI trial. The strontium citrate sold as a supplement has no fracture trials at all, so its evidence is limited.

Why does strontium increase bone density scores?

Strontium is denser than calcium, so strontium in bone inflates DXA readings; correction studies suggest roughly half the apparent gain is measurement artifact. Tell whoever orders your scan that you take strontium.

Is strontium safe?

Strontium ranelate was linked to more heart attacks, blood clots and rare, potentially fatal DRESS syndrome, and it was restricted in Europe and withdrawn. Strontium citrate has had no equivalent safety review and is not appropriate as a casual bone supplement.

How should strontium be taken with calcium?

Strontium was dosed at bedtime, on an empty stomach at least 2 hours after food, calcium or dairy, which sharply reduce its absorption. Take calcium with meals and strontium at least 2 hours apart.

Scientific references

Where to buy

Swanson Vitamins, Strontium Citrate, 340 mg, 60 Capsules

View on iHerb

Ships to 180+ countries · welcome discount for new customers

Referral link — this site may earn a commission on purchases.

Related in Women's health