Nutrition science came into being because of the discoveries of the roles of certain nutrients in disease development. Examination of the early medical literature is especially revealing in this respect. The Egyptian papyri, the early Greek writings, the monastic scripts, and even passages of the bible describe the role of food in the prevention or treatment of diseases. Assessment of the nutritional status of populations as well as individuals occurs at several levels. Overall assessment examines birth and death statistics, life span, family size, economic factors, food distribution, food handling and preservation, and food disappearance from the marketplace. These measures or databases are all useful in assessing the likelihood of intake adequacy for large populations and can serve as barometers of diet adequacy and inadequacy. The scientists providing the recommendation for micronutrient requirements and their associated recommended dietary allowances assume that the consumer is healthy with no inherent metabolic or physiologic problems.