Vitamin B12 has the largest and most complex chemical structure of all the vitamins. Most of its functions are related to its coenzyme activity, such as enzymes required for the production of DNA during cell division, as well as for the proper disposal of homocysteine.* B12 is also necessary for the maintenance of a healthy nervous system.* Quatrefolic is a registered trademark of Gnosis S.p.A. and protected by U.S. Patent 7,947,662.A number of drugs can affect vitamin B12 levels or its utilization. At Protocol For Life Balance, our mission is to provide high-quality, affordable solutions that empower people to lead happy lives. Our extensive line of premium natural health products uses well-researched ingredients that meet the highest quality standards. Every Protocol For Life Balance product must pass a rigorous internal review to ensure relevance, efficacy, and quality.