- 3 Myths About Strontium
- The 3 Different Types of Strontium Salts You Should Know About
- Myth#1: Strontium Increases Fracture Risk
- Myth#2: Strontium Supplements Have Side Effects
- Myth#3: Strontium Skews DXA Results Too Much To Be Reliable
- Deciding on Dosage
- When to Take Strontium Citrate
- Strontium Safety Issues
- Key Takeaways From This Article
- Strontium FAQs
What is Strontium?Strontium is a mineral from the earth that is naturally found in your body in small amounts. In fact, 99% of the total amount of strontium in the body is found in bone, a trait it shares with calcium. Experts now believe strontium is, “an essential trace mineral necessary for the optimal normal development and accretion of peak bone mass, and the sustained health of our bones.” Along with bone-building elements calcium and magnesium, strontium is a member of the elements in Group 2 on The Periodic Table – meaning it shares some similar chemical properties. Strontium is found in varying amounts throughout the world in the soil, and thus in plants grown in the soil, and in the water – so it is a natural part of our diet. In the U.S., Canada and Europe, the typical diet contains 2–4 mg strontium/day. However, commercially-produced plant foods grown on fields using synthetic fertilizers, pesticides and herbicides have far lower levels of strontium than their organic counterparts. Plus, it is well-known that our consumption of plant foods is far below recommended amounts – so it is unlikely you are getting sufficient strontium in your diet. To learn about the most strontium-rich foods, check out our Strontium Food Sources page. Consumers of conventionally-grown foods are at risk of strontium deficiency, which, as you will soon see, is a factor that increases our risk of osteopenia/osteoporosis as we age. However, you may have heard some less-than-confidence inspiring things about strontium. So I’m here to set the record straight…
3 Myths About StrontiumHaving reviewed the published research on the different forms of strontium: natural strontium, the strontium ranelate drug, along with the radioactive form of strontium, I can confidently assure you that the natural form of strontium, strontium citrate, is a safe and effective bone health supporter. That goes for both the density and the tensile quality of your bones. (I’ll explain more in detail on how they differ shortly.) But there are still several misconceptions about strontium citrate pills:
- Strontium Increases Fracture Risk. Some strontium critics conclude that strontium causes the outer cortical bone to become thicker, reducing tensile strength (resistance to breaking under tension) and increasing the risk of fractures. However, peer-reviewed research shows otherwise.
- Strontium Supplements Have Side Effects. Strontium has been painted a villain due to undesirable and serious side effects of one form, the drug, strontium ranelate…
- Strontium Skews DXA Results Too Much To Be Reliable. Since strontium is denser than calcium, it affects bone improvement readings on a DXA scan. So, some question whether strontium is really increasing bone density or if improvements are just a false positive result.
The 3 Different Types of Strontium Salts You Should Know About
Natural Strontium SaltsThe element strontium is present in natural strontium salts. The most common stable strontium salts are strontium sulfate and strontium carbonate, which are found in soils, and strontium citrate which is used for nutritional supplements. Stable strontium itself has never been found to cause any harmful effects — with one caveat: to maintain proper balance between calcium and strontium, more calcium than strontium must be consumed. In more than 100 years of research on strontium, including a number of recent human studies discussed below, no adverse effects have been reported for any natural stable strontium salt when more calcium than strontium is consumed. Natural strontium salts are safe (at reasonable dosages, of course) and highly beneficial. Neither of the two forms discussed next are safe. In fact, each has harmful side effects…
Strontium Ranelate DrugStrontium’s beneficial effects in the treatment of osteoporosis were reported way back in 1910 — but strontium products never entered the market back then due to confusion between the normal, stable forms of strontium with its radioactive isotopes. What everyone heard about was radioactive strontium for building atomic bombs – and no company was willing to launch healthful strontium products with public perception as it was. But more recently, the poor track record and serious side effects of the osteoporosis drugs, renewed interest in the bone health benefits of strontium by the French pharmaceutical company, Servier. Since natural minerals cannot be patented, Servier developed a chemical drug form of strontium called strontium ranelate. Servier now had a patentable, exclusive strontium bone drug which was sold beginning in the early 2000’s under the trade name ProtelosTM. Ranelic acid is the synthetic compound used to create the unnatural strontium salt, strontium ranelate. Unfortunately, this drug form of strontium is potentially harmful. For additional sources on its toxicity go to Toxin Profiles and the Agency for Toxic Substances & Disease Registry. Strontium Ranelate has a long list of adverse side-effects, starting with common ones like:
- Skin irritation
- Loose Stools
- Venous thromboembolism
- Serious autoimmune reactions, such as DRESS (the acronym for drug rash, eosinophilia and systemic symptoms)
Radioactive StrontiumRadioactive strontium is formed in nuclear reactors or during the explosion of nuclear weapons. Therapeutically, radioactive strontium is used to treat metastatic cancer but can damage bone marrow and act as a potential carcinogen itself at high doses. Radioactive strontium isotopes (85Sr and 89 Sr) are also used as delivery agents for chemotherapy drugs and for diagnostic purposes in kinetic studies. (Kinetics is the study of the rate at which chemical processes occur.) Radioactive strontium is not sold as supplements! Radioactive strontium, which shows up in imaging and is easily traced, is often substituted for calcium in kinetic research because strontium and calcium behave very much alike in the human body. All forms of strontium and calcium have strong bone-seeking properties, and both share common transport pathways, so they compete for absorption in the intestines and for reabsorption in the kidneys. I want to underscore here that this is a competition that calcium always wins, which explains why:
- Strontium cannot displace calcium when adequate supplies of calcium are present.
- Strontium supplements should be taken at a different time of day from calcium, or else little, if any, strontium will be absorbed.
Myth #1: Strontium Increases Fracture Risk
Some strontium critics claim that strontium causes cortical bone to become thicker, and since cortical bone is less flexible, may increase risk of fractures.The scientific facts are so different from these assertions, it’s unclear why they publish such misinformation. The very tiny amount of strontium ions that deposit in our bones prefer to do so in trabecular, not cortical bone. Trabecular bone is the soft, spongy, more metabolically-active inner portion of our bones. Cortical bone is their hard, outer layer. If your bones were M&Ms, cortical bone would be the outer candy shell and trabecular bone the soft chocolate center. Some strontium critics assert that strontium deposits primarily in cortical bone and that somehow translates into reduced bone strength. They base their claims on these 2 studies:
- Boivin, Deloffre, Perrat, et al.. Strontium distribution and interactions with bone mineral in monkey iliac bone after strontium salt (S 12911) administration. J Bone Miner Res. 1996 Sep;11(9):1302-11.
- Blake and GM, Fogelman I. (2006 JBMR 21(9) 1417-24 Strontium ranelate: a novel treatment for postmenopausal osteoporosis: a review of safety and efficacy. Clin Interv Aging. 2006;1(4):367-75.
Key Takeaways From This Article
- Strontium delivers a unique combination of bone health benefits no other nutrient provides. Strontium is the only mineral in our bones that both lowers the rate of bone resorption and promotes the rate at which new bone is built.
- Three types of strontium salts are in use today: (1) Natural stable strontium, e.g., strontium citrate, (2) Unnatural stable pharmaceutical strontium called strontium ranelate, and (3) Radioactive (unstable) strontium.
- Natural strontium salts, (strontium citrate), are safe (at the dosages discussed above and when twice as much calcium is consumed as strontium) and highly beneficial; neither strontium ranelate nor radioactive (unstable) strontium is safe.
- Strontium ranelate comes with risks of unwanted side effects. The long list of adverse side-effects attributed to strontium – ranging from commonly seen adverse effects like nausea and skin irritation to possibly deadly effects like venous thromboembolism and serious autoimmune reactions, such as DRESS – are caused by ranelic acid (the “ranelate” portion of strontium ranelate), not strontium.
- The use of strontium ranelate has never been approved in the U.S. and is now significantly restricted in Europe, while strontium citrate is freely available.
- Don’t worry about strontium taking the place of calcium in your bones. Strontium and calcium share a common carrier system in the intestinal wall, which will always choose to carry calcium rather than strontium from our digestive tract into our bloodstream. Strontium competes with calcium for absorption – and calcium wins every time. Also, strontium is eliminated more readily than calcium from kidneys.
- Strontium is almost twice as large as calcium, and its larger size impacts DXA readings. Available data indicate that approximately 10% of the increase seen in BMD is due to strontium’s larger size – which also means that 90% of the increase seen in BMD is accurate. Besides, strontium has been shown to reduce fracture risk independent of bone density. In other words, whether your bone density increases or not, strontium reduces your risk of breaking a bone!
- Strontium’s beneficial effects are not due to its replacing calcium in your bones. They are the result of strontium’s bone-building effects on a very wide range of key molecules involved in bone remodeling.
- Strontium increases our ability to absorb and deposit calcium in our bones– yes, calcium. And that’s another reason why the Bone Builder Pack of AlgaeCal Plus and Strontium Boost have not only slowed bone loss, but built new bone for the thousands of people who’ve tried it.
If you have either osteopenia or osteoporosis, you will receive the most benefit from a 680 milligram (mg) per day dose of strontium citrate.
If your bones are now in great shape, you may still wish to consider supplementing with strontium citrate at a dose of 340mg per day. This dose will help protect and maintain the long-term health of your bones.
Avoid consuming calcium for at least 2 hours before or after taking strontium. Certain foods and medications contain calcium as well as calcium supplements. Ideally, take strontium at night right before bed.
Calcium and strontium are chemically similar and compete at the same sites for absorption. If you take them at the same time, calcium will out-compete strontium, and you will not get the benefit of strontium
No. Strontium is not more readily absorbed than calcium. Both minerals use the same transport and absorption mechanisms, and furthermore, calcium will always be preferentially absorbed over strontium. This is why, to receive benefit from supplemental strontium, it should always be taken 3-4 hours apart from when calcium is consumed.
Could strontium citrate continue to deposit over the years, causing any adverse effect on our bones? Is there a maximum level of safe strontium in bones?
Although supplemental strontium does continue to become part of the bone matrix for as long as has been studied in the research (5 years), strontium citrate does not negatively affect bone mineralization or bone quality. In fact, strontium improves both. This was a finding from the clinical trials conducted as part of the Ryerson and McMaster University Strontium in Bone Research Study.
All natural, stable forms of strontium improve bone’s ability to undergo physical stress and resist fracture. That’s due to the numerous mechanisms of strontium to build and maintain healthy bones. Strontium increases the amount of osteoblast (remember, bone-building) precursor cells and their differentiation into mature osteoblasts. It also increases collagen type I synthesis and bone matrix mineralization, but inhibits the differentiation, maturation and activity of osteoclasts (bone-resorbing cells).
Furthermore, strontium greatly improves our production of new bone and bone quality via its effects on our osteoblasts and osteoclasts, not by taking the place of calcium in our bones. The number of calcium ions replaced by strontium ions in our bones is extremely small, and remains so because strontium is much more rapidly removed from bone than calcium.
Research conducted for 36 months on human hip bone tissues from postmenopausal osteoporotic women treated with strontium ranelate), found a very small number of calcium ions were replaced by strontium ions in the hydroxyapatite crystals in newly formed bone. It was a strontium substitution of up to one atom in every one hundred calcium atoms being replaced.
However, the thickness and length of the bone mineral crystals were not affected, and there was no indication of a change in human bone tissue quality. Let me repeat, the strontium ions in strontium ranelate exert all strontium’s beneficial effects; the ranelic acid portion is what is responsible for the adverse side-effects seen with this drug.
The only potential for concern with natural strontium supplementation would be IF calcium intake were low, AND strontium intake high. One human study reported an adverse effect from consumption of high levels of natural strontium. That was a paper published in 1996 showing an increased incidence of rickets in children in the Sivas province of Turkey, due to high levels of strontium in the soil AND a low intake of calcium. The recommendation made to prevent this: calcium supplements.
If you are taking AlgaeCal Plus and Strontium Boost, (the Bone Builder Pack) a daily dose of AlgaeCal Plus for bone building is 4 capsules per day, which provides 720 mg of calcium. The Standard American Diet, on average, also provides ~400-600 mg of calcium per day. So total calcium from all sources is anywhere from 1100 – 1300 mg per day. Strontium Boost provides 680 mg of natural strontium citrate per day in 2 capsules. This bone-building combination provides you with twice as much calcium as strontium, which is backed by the research.
You can further boost your ability to absorb strontium and get the most from your strontium supplement if you: (1) Ensure your intake of vitamin D3 is adequate; (2) Avoid consumption of processed foods– all contain phosphate additives, which interfere with strontium absorption.
Yes, the natural, stable strontium salt, strontium citrate, has shown no adverse effects when more calcium than strontium is consumed.