The skin protects and covers dynamic internal systems. The largest organ in the body, the skin provides many important indicators for the clinician. This 15-page Companion Guide includes three detailed, annotated tables describing conditions like acne and xerosis and their associations with nutrient imbalances. The roles of proteins, fats, carbohydrates, minerals, vitamins, and phytonutrients and how to detect deficiencies and excesses are described. If you want to interpret changes in skin color, understand the upstream causes of pallor or lesions, and know how diet impacts hair distribution, this Companion Guide is the key.