Diet has a powerful yet complex effect on health. Dietetics is a science that deals with the adequacy of diets during normal life cycle and modifications required during diseased conditions. According to American Dietetic Association 'Dietetics is the integration and application of principles derived from the science of nutrition, biochemistry, physiology, food management and behavioral and social sciences to achieve and maintain people's health'.

Menu planning is the process of planning and scheduling intake of meals for general or specific individual requirements. The following terms and concepts are widely used and a clear understanding of these terms makes menu planning efficient.