Strontium may play a role in bone formation, and also may inhibit bone breakdown.¹ Preliminary evidence suggests that women with osteoporosis may have reduced absorption of strontistaum.² The first medical use of strontium was described in 1884. (Strontium supplements do not contain the radioactive form of strontium that is a component of nuclear fallout.) Years ago in a preliminary trial, people with osteoporosis were given 1.7 grams of strontium per day for a period of time ranging between three months and three years; afterward, they reported a significant reduction in bone pain, and there was evidence suggesting their bone mass had increased.³ More recently, in a three-year double-blind study of postmenopausal women with osteoporosis, supplementing with strontium, in the form of strontium ranelate, significantly increased bone mineral density in the hip and spine, and significantly reduced the risk of vertebral fractures by 41%, compared with a placebo.⁴ The amount of strontium used in that study was 680 mg per day, which is approximately 300 times the amount found in a typical diet. Increased bone formation and decreased bone pain were also reported in six people with osteoporosis given 600 to 700 mg of strontium per day.⁵  Although the amounts of strontium used in these studies studies was very high, the optimal intake remains unknown. Some doctors recommend only 1 to 6 mg of supplemental strontium per day—less than many people currently consume from their diets, but an amount that has begun to appear in some mineral formulas geared toward bone health. Strontium preparations, providing 200 to 400 mg per day, were used for decades during the first half of the twentieth century without any apparent toxicity.⁶ No significant side effects were observed in people taking large amounts of strontium; however, animal studies have demonstrated defects in bone mineralization, when strontium was administered in large amounts in combination with a low-calcium diet. People interested in taking large amounts of strontium should be supervised by a doctor, and should make sure to take adequate amounts of calcium. It should be noted that, although supplementing with strontium increases bone mineral density, only part of the increase is real. The rest is a laboratory error that results from the fact that strontium blocks X-rays to a greater extent than does calcium.⁷ People taking large amounts of strontium should mention that fact to the radiologist when they are having their bone mineral density measured, so that the results will be interpreted correctly.

 

Levels of strontium in the water supply have been shown to correlate with the risk of dental caries in communities with similar fluoride levels.⁸ Compared with children with fewer cavities, enamel samples from children with high numbers of caries have been found to contain significantly less strontium.⁸ However, supplementation with strontium has not yet been studied as tooth decay prevention.