The role of
vitamins in colorectal neoplasms has garnered significant attention due to their potential influence on cancer risk. This narrative review explores the current evidence on how various
vitamins may affect the development of colorectal neoplasms. With the rising global incidence of colorectal cancer, understanding these factors is essential for effective prevention. Cancer's significant mortality rates underscore the importance of such research. Method: Our study was conducted on the PubMed database, using the keywords ("Colorectal Neoplasms"[Mesh]) AND "Vitamins"[Mesh] from ۲۰۰۰ to ۲۰۲۴. To narrow our focus, we filtered the results to include only clinical trial papers. This search yielded approximately ۶۰ papers, of which ۴۷ were selected for review. Result: Recent clinical trials have established that vitamin D is crucial in regulating lipid metabolism and functions as a selective modulator of the estrogen receptor, which may influence the development of precursor lesions for
colorectal cancer (CRC). Specifically, studies indicate that plasma concentrations of ۲۵-hydroxyvitamin D (۲۵(OH)D) above ۲۹ ng/mL are inversely correlated with the risk, incidence, and mortality associated with CRC. Vitamin D۳, administered either alone or in combination with calcium, has been shown to enhance DNA mismatch repair mechanisms, increase TGFβ۱ expression, and reduce paracrine growth stimulation within the colorectal epithelium. This synergistic effect is hypothesized to act as a potential chemopreventive agent against neoplasms by modulating the expression of critical proteins such as APC, β-catenin, and E-cadherin. However, contrasting evidence exists, as some studies indicate that vitamin D and calcium supplementation does not significantly reduce the risk of CRC recurrence over a span of ۳ to ۵ years. Additionally, research on B vitamin supplementation, particularly
folate and vitamin B۶, has suggested that increased intake may lower CRC risk in women, especially when accompanied by improved folate-related DNA biomarkers. Nonetheless, it is important to note that some studies propose that only individuals with low plasma
folate levels derive benefits from these dietary adjustments. Moreover, alternative factors, including the influence of other dietary components and the potential increased risk of other cancers associated with folic acid supplementation compared to dietary folate, warrant consideration. Conclusion: In summary, while vitamins, particularly vitamin D and B vitamins, may play significant roles in the prevention and management of colorectal cancer, the evidence remains complex and sometimes contradictory. Further research is essential to clarify the mechanisms through which these
vitamins exert their effects and to identify specific populations that may benefit most from supplementation.