The secret ingredient which incrreases Bone Mineral Density in some “Natural Supplements” sold in the US is Strontium Citrate. Strontium has more than twice the atomic weight of Calcium. Bone places Strontium where Calcium belongs in the bone crystal latice. Bone with Strontium has a higher Bone Mineral Density than bone with only Calcium.
But is it stronger? Increasing Bone Mineral Density with Fluoride makes bone more brittle. We do not know all the effects of Strontium, although we do know some. A Strontium atom is bigger than a Calcium atom. Therefore, using Strontium istead of Calcium can distort the crystal latice that gives bone it’s rigid strength. That probably is not good.
Strontium Ranelate is available in Europe. The French company that makes Strontium Ranelate stresses the ability of Ranelate, not Strontium, to strengthen bone. There are two European human studies showing a decrease in Fracture Risk. The European FDA has approved the drug. The company has not requested approval from the US FDA.
Strontium Citrate is available in the US and elsewhere. It is much cheaper to make than Strontium Ranelate. They might be similar. No studies have been done on humans to asses the effect of Strontium Citrate on Fracture Risk. Increased bone mineral density sounds nice, but the real question is: Can Strontium Citrate reduce fracture risk? We just do not know.
Jay Ginther, MD