فهرست نشریات علمی دسترسی آزاد ایران

Ionizing radiation is a well-recognized human carcinogen arising from environmental and medical exposures such as diagnostic imaging and radiotherapy. Its carcinogenic potential is mainly mediated through DNA strand breaks, excessive generation of reactive oxygen species (ROS), sustained oxidative stress, and genomic instability that collectively drive malignant transformation. Dietary vitamins have demonstrated potential in modulating these radiation-induced mechanisms through their antioxidant, DNA-repair, and regulatory activities. This review attempts to assess the present knowledge of vitamins A, C, D, E, and B complex in restricting radiation associated carcinogenesis. Vitamins C and E are key antioxidants and prevent the formation of ROS during radiolysis and the peroxidation of cell membrane lipids, respectively. Folate, vitamin B6 and vitamin B12 are responsible for regulating one-carbon metabolism, DNA synthesis and methylation thus ensuring chromosomal integrity. Vitamin D, through its receptor (VDR), promotes DNA repair, regulates apoptosis, and enhances immune defense, while vitamin A derivatives maintain epithelial integrity and exhibit anti-inflammatory effects. Together, these nutrients regulate cell cycle regulation, epigenetic stability, and oxidative damage. As evidence, there appears to be a possible advantage for combined supplementation compared to single agents. However, the clinical results are situation-specific, as illustrated by the chronic increase in risk for lung cancer with excessive intake of the beta-carotene in smokers. Future trials will need to improve dosage, timing, and personalized approaches for safe use of vitamins in cancer prevention.