This randomised controlled trial revealed that six-month oral supplementation with Lactobacillus complex capsules including Lactobacillus lactis, Lactobacillus acidophilus, and Streptococcus lactis twice daily can suppress expression of OS markers including CAT, GSH, GSSG, 8-oxodG, and F2-IsoPs and inhibit the NRF2, p38 MAPK, and JNK pathways in CRC patients after surgery. Here, CAT is linked to colorectal carcinoma.