While the cosmetology industry has long thrived on a narrative of external solutions, the realm of dermatology is evolving, acknowledging the undeniable truth, that true skin health is also a function of the right nutrition. This is a paradigm shift that recognizes our bodies as integrated ecosystems and explains why some respond and others do not. The radiance of our skin and the vitality of our hair serve as external mirrors of our internal health and while these signs are often attributed to genetics or external care routines, they are, in fact, profoundly influenced by a significant factor: nutrition, which plays on epigenetics and actual gene expression, as documented in various studies. “Nutrition in Dermatology: An Evidence-Based Guide” takes you through the pivotal role that nutrition plays in the realm of skin and hair function and maintenance. This book is not merely an exploration of vanity; it is an exploration of the fundamental and intricate connections between what we consume and the canvas that is our skin. Drawing from a wealth of scientific research and expert insights, we will explore the effects that the foods we eat have on our skin and hair. From micronutrients like vitamins, minerals, and antioxidants to macronutrients like protein and fatty acids, the significance of these nutritional elements will be translated to dermatological practices, shedding light on their impact on our body. This book underscores the profound implications of nutrition in preventing and managing various dermatological concerns and conditions. It is a guide for dermatologists seeking well-rounded interventions for promoting our skin’s intrinsic mechanisms for protecting itself. And all of it is backed by data stratified into good evidence, moderate evidence, and poor evidence, which can give the reader the prowess to make an informed decision. As we traverse the chapters, we will encounter not just a compilation of data, but a comprehensive understanding of nutrition’s impact on cellular regeneration, inflammation modulation, and hormone regulation, which is ushering in a new era of patient care because gone are the days when we negate the role of nutrition in body processes and push it under a rug.