Vitamin B12 plays a vital role in red blood cell formation, cell metabolism, nerve and brain function, and the production of DNA. It is found naturally in food in animal sources. B12 deficiency is common. This can be due to lack of dietary sources, and/or from the inability to properly absorb B12 despite adequate intake.

B12 injections have proven to be a safe, nontoxic way to replete B12 levels. It involves an intramuscular injection. Benefits of the B12 shot can include increased energy levels and concentration, metabolism improvement and weight loss help, better sleep, and a boost to the immune system. The benefits of the B12 injection are typically felt 24-72 hours after the injection, and this can vary from person to person.