Celiac disease (CD) was once viewed as a rare disorder, but it is now known to directly affect the lives of millions worldwide. Over the years, many adults with CD have been found to persist in having poor mental and physical health with poor quality-of-life, despite their adherence to a gluten-free diet. The reasons for the failure of a gluten-free diet to restore good general health are unsettled. Both genetic predisposition and environmental factors contribute to the pathogenesis of CD, which results in a small bowel inflammatory reaction that leads to tissue destruction. CD is characterised by a dysregulated immune response to gluten proteins. This book discusses risk factors, health implications and dietary management of celiac disease.