The results revealed that, among the arm receiving combined Ca and vitamin D ONS, serum levels of 1,25-dihydroxyvitamin D (25(OH)D), osteocalcin, parathyroid hormone (PTH), and urine Phosphorus (P) were lower, whereas no incidences of hypercalciuria were noted on spot testing based on the urinary Ca-to-creatinine ratio. This evidence concerns the gene PTH and Hypercalciuria.