I have found a connection between vitamin B12 deficiency and osteoporosis. Calcium and vitamin D are often mentioned here but not vitamin B12. It can also cause subacute combined degeneration of the spinal cord. I wonder if people, here, with osteoporosis have had their vitamin B12 tested, ferritin and folate are usually tested with it.
“Tissues and organ dysfunction. . . . . . . . . .Deficiency can also result in osteoporosis, with reduced bone derived alkaline phosphatase and plasma osteocalcin.”
The BMJ CLINICAL REVIEW Vitamin B 12 DEFICIENCY Alesia Hunt Page 3 - 2nd and 3rd paragraphs.