Conditional knockout mice for osteoblast/osteocyte-specific disruption of the FGF23 gene with CKD induced by adenine showed more severe LVH, although the elevation of serum FGF23 levels was suppressed compared to that in mice with only CKD, and therefore, increased bone FGF23 is necessary rather than harmful to protect against the cardiorenal consequences of elevated tissue phosphate. Here, FGF23 is linked to chronic kidney disease.