GLA and sarcopenia: Together with parathyroid hormone, vitamin D and hypolactasia as regulators and modulators of systemic calcium levels, we investigated the dephosphorylated, uncarboxylated Matrix-GLA-protein as a surrogate parameter of vitamin K. Neither vitamin D deficiency nor hypolactasia associated with sarcopenia and parathyroid hormone significantly associated with sarcopenia, as defined by rLM20.