(1) Background: For normo-nourished colorectal cancer patients, the need for immunonutrients after elective surgery is not known. (2) Methods: Multicenter, randomized, double-blind, phase III clinical trial comparing the postoperative diet with 200 mL oligomeric hyperproteic normocaloric (OHN; experimental arm) supplement vs. 200 mL immunonutritional (IN) (active comparator) supplement twice a day for five days in 151 normo-nourished adult colorectal-resection patients following the multimodal rehabilitation ERAS protocol. The proportions of patients with complications (primary outcome) and those who were readmitted, hospitalized for <7 days, had surgical site infections, or died due to surgical complications (secondary outcome) were compared between the two groups until postoperative day 30. Tolerance to both types of supplement and blood parameters was also assessed until day 5. (3) Results: Mean age was 69.2 and 84 (58.7%) were men. Complications were reported in 41 (28.7%) patients and the incidence did not differ between groups (18 (25%) vs. 23 (32.4%) patients with OHN and IN supplement, respectively; p = 0.328). No significant differences were found for the rest of the variables. (4) Conclusions: IN supplement may not be necessary for the postoperative recovery of colorectal cancer patients under the ERAS regimen and with normal nutritional status at the time of surgery.
Keywords: diet; dietary supplements; gastrointestinal neoplasms; immunity; malnutrition; nutrients; nutritional status; perioperative care; postoperative complications.