The triage theory posits that modest micronutrient deficiencies may induce reallocation ofnutrients to processes necessary for immediate survival at the expense of long-term health. Neglectedprocesses could in time contribute to the onset of age-related diseases, in which oxidative stress isbelieved to be a major factor. Vitamin B12 (B12) appears to possess antioxidant properties. This reviewaims to summarise the potential antioxidant mechanisms of B12 and investigate B12 status in relationto oxidative stress markers. A systematic query-based search of PubMed was performed to identifyeligible publications. The potential antioxidant properties of B12 include: (1) direct scavenging ofreactive oxygen species (ROS), particularly superoxide; (2) indirect stimulation of ROS scavengingby preservation of glutathione; (3) modulation of cytokine and growth factor production to offerprotection from immune response-induced oxidative stress; (4) reduction of homocysteine-inducedoxidative stress; and (5) reduction of oxidative stress caused by advanced glycation end products.Some evidence appears to suggest that lower B12 status is related to increased pro-oxidant anddecreased antioxidant status, both overall and for subclinically deficient individuals compared tothose with normal B12 status. However, there is a lack of randomised controlled trials and prospectivestudies focusing specifically on the relation between B12 and oxidative stress in humans, resulting ina low strength of evidence. Further work is warranted.
van de Lagemaat, E. E., de Groot, C. P. G. M., & van den Heuvel, E. G. H. M. (2019). Vitamin B12 in Relation to Oxidative Stress: A Systematic Review. Nutrients, 11(2), . https://doi.org/10.3390/nu11020482