For the last 30 years, polyphenols were in the centre of research work worldwide. Silymarin, an extract from a medicinal plant Silybum marianum, also known as milk thistle, has a special place in this group, having been used in human medicine for the management of liver diseases since ancient times. Accumulating scientific evidence indicates that silymarin is characterised by a wide range of protective pharmacological activities and this topic has received tremendous attention in recent years. However, until now there has been no single monograph addressing major questions related to silymarin chemistry, biochemistry and practical applications. The goal of this book is to provide up to date information about silymarin chemistry, biochemistry and molecular mechanisms of protective actions of this phytochemical with a special emphasis to its vitagene- and transcription factor-modulating properties. Silymarin applications in human diseases, including hepatoprotection, neuroprotection, anti-diabetic, anti-arthritis and other protective activities are reviewed. Immunomodulating, anti-inflammatory, anti-toxic protective activities of silymarin are characterised in detail. Practical applications of silymarin in poultry and animal industry with a special emphasis on its protective roles in gut health maintenance are also presented. This book will be of practical importance to medical and pharmaceutical scientists, including medical doctors, pharmacists, consultants, etc. as well as to poultry/animal scientists, poultry producers, nutritionists and vets, as well as to students of medical, biological and agricultural backgrounds. It can also be of interest for researchers in areas related to physiology, biochemistry, nutrition and veterinary medicine.