You really need B vitamins
The B vitamins are a group of eight water-soluble vitamins. They are coenzymes in a variety of metabolic processes in the body, and often work together—though each has a unique role as well. B vitamins are critical for building and repairing DNA and RNA, for producing energy, supporting mitochondrial function, and for synthesizing neurochemicals. And because they are involved in so many processes, deficiencies in B vitamins can lead to many problems. Are you getting enough B vitamins?
Vitamin B12 - cobalamin
B12 is a critical B vitamin involved in DNA synthesis and repair, detoxification, histamine metabolism, mitochondrial function, methylation, and many other processes in the body. Deficiency can lead to anemia, neurologic problems, and a number of other issues. B12 deficiency is relatively common, and certain groups are at significant risk. These include vegetarians, vegans, the elderly, and anyone with gut issues. B12 is found almost exclusively in animal foods, though is straightforward to supplement.