By Robert Gottesman, M.D.
New and exciting data has been released about a very promising nontoxic treatment for osteoporosis: the naturally occurring element strontium. Strontium lies directly below calcium on the periodic table of elements and that makes calcium, strontium and magnesium (which is just above calcium) all in the same chemical family. They are all naturally occurring metals with a 2+ valance that readily form into stable salts like calcium citrate, magnesium citrate and strontium citrate. They also form carbonates, sulfates, lactates and others. A recently published paper in the New England Journal of Medicine (NEJM) (1/29/04) suggests that it maybe at least as good a treatment for osteoporosis as currently available therapies including Fosamax (alendronate), Actonel, (risedronate), Evista (raloxifene ),and the newest treatment, the injectable parathyroid hormone Forteo (teriparatide).
Strontium was studied in both animals and humans from the early 1950s to the early1960s and was shown to have strong bone building properties. However, it promptly fell out of favor because atomic bomb testing converted a lot of the natural strontium into a completely unnatural radioactive isotope called strontium-90. This bad boy radioactive substance became widely disseminated throughout the world and because of its affinity for bones it got into our skeletons. Thanks to atmospheric nuclear testing, we probably all have minute amounts of strontium-90 incorporated into our bones and teeth today. Large exposures of strontium-90 are extremely toxic and linked to bone cancer, cancer of the soft tissue near the bone, and leukemia. It has a radioactive half life of 29 years, and some have speculated that the low level radiation emitted by trace amounts of strontium-90 may, in part, be responsible for the current epidemic of osteoporosis.
Strontium-90 is man made. Natural strontium on the other hand is stable, non-radioactive and appears to be completely nontoxic. The most recent NEJM article is a phase 3 trial that follows two other very positive multinational clinical trials. In this most recent one, 1,649 postmenopausal women with osteoporosis who had had at least one vertebral fracture were randomized to receive either 2 grams of oral strontium ( in the form of strontium ranelate) or placebo for three years. Both groups also took calcium and vitamin D. There were no negative side effects from the strontium except some transient diarrhea.
The positive effects on bone were dramatic. The lumbar spine, for instance, increased 8.1% in bone mineral density (it actually increased 14% but the authors corrected that number downwards for comparison because small amounts of strontium get deposited on the surface of the bone and strontium is more dense than calcium). This increase in bone density compares favorably with the alternative treatments such as Fosamax (6.2%), Actonel (5.9%)Evista (2.6%) and the parathyroid hormone (9% at 20 months).
More importantly, the authors note that strontium has both anabolic (bone building) effects and anti-resorption (anti-depleting) effects and therefore works differently than any of the other available agents. Unlike Fosamax and Actonel, which work strictly by decreasing bone resorption, strontium increases bone mass. Fosamax and Actonel merely thicken the old bone. Furthermore, fracture rates of the spine are reduced 41%, again favorably comparable to the pharmaceutical agents. In women over 70 years old, data shows that hip fractures are reduced by 36% and vertebral fractures are reduced by 59%. The conclusion by the author-experts assembled from France, Australia, Italy, Poland, England, Hungry, Germany, Denmark, Belgium and the USA was this: “Strontium ranelate given orally at 2 grams daily appears to reduce the risk of vertebral fractures rapidly, effectively and safely among postmenopausal women with osteoporosis.”
Strontium ranelate was developed by a large French pharmaceutical company (Institut de Recherches Internationales Servier; http://www.servier.com) and its sale is still restricted. I assume that they will patent the formulation and therefore will keep it off the market until all of the studies are finished. But I strongly suspect that we will find that strontium is the beneficial component and not the organic carrier (ranelic acid) since the earlier studies used strontium lactate and strontium carbonate with similar favorable results.
A Few Caveats in the Use of Strontium
Although strontium seems to be a remarkably benign supplement, there are a few guidelines to follow to maximize its benefit:
Calcium should not be taken simultaneously with the strontium since the calcium dramatically decreases the absorption of the strontium.
It should not be used as a treatment in children since it can alter the architecture of rapidly growing bones.
Traditional bone mineral tests like the DEXA will give artificially high results since strontium is much denser than calcium and a correction will need to be factored in.
As with all of the pharmaceutical agents, the long term safety of administration of strontium is unknown, but thousands of women have now taken it over the last decade.
Strontium is not a “magic bullet” and a comprehensive approach to regaining bone strength is still optimum. Other modalities of bone support include calcium, vitamin D, magnesium, vitamin K, progesterone, estrogen (in small amounts), testosterone (if necessary) and weight bearing exercise.
Robert Gottesman, M.D. is a practicing clinician in Santa Ynez, California who has been using natural hormones in his practice for many years. He has contributed greatly to Dr. Lee’s work over the years. He can be contacted at firstname.lastname@example.org.
Editor’s Note: Ask for strontium supplements at your local health food store or look for them on the web. One brand name by Advanced Orthomolecular Research out of Calgary, Canada is called Strontium Support, which contains 720 mg per capsule.