187 patients scheduled for primary lumbar spine surgery for the treatment of lumbar disc herniation or lumbar spinal stenosis were randomized to receive a peri-operative multi-modal nutritional management (MNM) protocol or the standard nutritional protocol. Outcomes of interest included electrolyte levels (potassium, calcium, sodium), the incidence of electrolyte disorders and adverse events, transfusion rate, albumin and hemoglobin levels, and length of stay. Results revealed significantly favourable levels of electrolytes, lower incidences of electrolyte disorders, favourable levels of albumin and hemoglobin, shorter length of stay and a lower incidence of wound drainage in the MNM group compared to the control group.