We only use physician-grade, top-quality supplements that are backed by research studies. Dr. Nolley does a great deal of research to check quality, potency, synergistic formulations, bio-availability, and whether important standards are met by the manufacturing facilities including testing and monitoring for potential contaminants including heavy metals, pesticides and microbiological organisms. You won’t be guaranteed this level of quality assurance when buying off the shelf, online, or at a store.