Bone strength is maintained through cycles of bone formation and resorption via specialized cells called osteoblasts (formation) and osteoclasts (resorption). When bone resorption starts to exceed bone formation, bone strength suffers, leading to conditions like osteoporosis.[1]
When absorbed, almost all of the strontium ends up in bones, teeth, and joint structures.[2] Once incorporated into the bone, calcium and strontium appear to behave similarly.[3][4][2] Strontium may promote the new formation of bone by increasing the number of osteoblasts and preventing their destruction.[4][2]
Though we still don’t have a complete understanding of how strontium works in the body, one possible mechanism may be that it works its way into bone cells to fill the gaps left by excessive resorption.[3][4] When used as a toothpaste additive, strontium is believed to work by blocking the exposed dentine tubules that produce dental hypersensitivity.[5][6][7]
In some preclinical (animal) studies, strontium seems to reduce pro-inflammatory cytokines to reduce inflammation.[2] If the same anti-inflammatory activity occurs in humans, that could explain why it has shown some evidence of being useful for reducing skin irritation and itching as part of topical ointments.[8][9][10]