The childhood and adolescence is an important period for establishing lifelong health. If parents want their children to live a healthy life, they should fix their children a nutritionally balanced diet and they should encourage their children to have a healthy eating habits and active physical activity. The beginning of lifelong health should be breastfeeding which reinforces immunity. What parents need to do is preparing nutritionally balanced meals at certain place at regular times. Children themselves control the amount of food they need to take. The parents should be a role model of their children to improve their childrens' healthy lifestyle. After 2 years of age, fat intake must be gradually decreased to 30∼35% of total energy intake. The parents should limit their children eating saturated or trans fatty acids. Sweet or salty taste should be given as late as possible, and the parents should make efforts to give their children fruits and vegetables at each meal. Also they have to serve milk, dairy products, beans, tofu which are abundant of calcium. Traditionally, physicians has been treating sick children but nowadays physicians have to ask about childrens' health before anything else and inform the parents what to do to keep their children healthy.