A small body of evidence suggests that berberine supplementation may reduce the recurrence rate of colorectal adenomas, which commonly evolve into CRC over time.[1] When added to chemotherapy treatment, some studies showed that some herbs used in Traditional Chinese medicine could improve quality of life, reduce some chemotherapy side effects, and enhance the tumor response to certain treatments (but the quality of evidence was low and results were inconsistent.)[2][3][4] Probiotics and synbiotics could reduce infections and complications after CRC surgery.[5] Vitamin D supplementation has also been studied, but conflicting study results prevent any conclusions about its ability to protect against CRC.[6][7]