Adolescence is a critical period of the lifespan, characterised by major physical, chemical and emotional changes. The need for a nutritionally adequate diet is of paramount importance to ensure optimum growth and development. Eating behaviours that are learned early in life are maintained in adulthood. Nutritional inadequacies influence not only adolescents’ health but also risk for major chronic diseases in adulthood. As teens become more independent, they make more of their own food choices. Factors that adolescents viewed as influencing their food choices include hunger, appeal of food, time considerations of adolescents and parents, convenience of food, food availability, parental influence on eating behaviours, benefits of foods, situation-specific factors, mood, body image, habit, cost, media and vegetarian lifestyle. The present book has reviewed comprehensively key features of adolescent eating patterns which includes meal skipping, snacking, fast food consumption, inadequate intake of fruits, vegetables, and dairy and other calcium-rich foods, and unconventional dietary patterns such as adopting specific weight loss diet.