This book is intended for those who seek to improve suboptimal health, practice preventive healthcare, and pursue personalized medicine using cGMP herbal products. Suboptimal health refers to conditions such as being overweight or experiencing fatigue, which may precede or underlie a disease but are otherwise normal. In East Asia, cGMP herbal products have long been used as medicines to address patterns of pathology, including suboptimal health, in addition to the vitamin and mineral supplements recommended by modern Western medicine. In the United States, the same cGMP herbal products are available and labeled as dietary supplements. By using herbal products to treat suboptimal health conditions, we can prevent the development of diseases and save significant costs to individuals and society.