VITAMIN B4: It is an essential vitamin for the normal functioning of the brain, the nervous system, for the formation of blood and various proteins, and for the proper functioning of various metabolic processes. I actually correct myself. The so-called Vitamin B4 is not such, as well as B8, F, G and H. A vitamin. it is essentially an organic compound that activates one or more enzymes essential for the body to perform vital functions. By definition they cannot be synthesized by the body and it is necessary to ingest them, except for D, which is generated by contact with sunlight. A problem that will have to be addressed and solved as astronauts move beyond Mars. As it was discovered that some vitamins were synthesized by humans, they ceased to be called so, and for this reason there is no talk of B4, B8, F, G, H, I, J, L.