I'm no expert at all on osteopenia/osteoporosis but have been taking the Alive! Bone Support (formerly called Bone Formula) for several years after buying it for a friend healing from a broken neck. A DEXA last year was almost identical to one six years earlier so it's probably helping. After comparing the two DEXAs, my PCP stopped recommending I consider taking Fosamax at least.

The 4-tablet dose contains 1300 mg calcium from red algae, 100 mg vitamin D3, 150 mg vitamin K2 and magnesium and some fruit, vegetable and greens stuff and an insignificant 9 mg of strontium also from the red algae.

I also take orthosilicic acid because a few studies I read noted its role in bone renewal (brand name Bio-Sil) and Biotin Forte (3,000 mcg biotin and 30 mg zinc). The latter two also help hair, skin and nails in theory. I have thick hair that seems to be growing faster since adding the Bio-Sil. I'm not sure that that's a desired side effect but it's interesting. And, to me, is a reminder that the body's innate propensity is to regenerate when the environment supports it in ways we don't yet fully understand.

But again I'm no expert about this stuff. Am just taking stuff that peer-reviewed studies suggest are important in bone health and renewal.