Dietary recommendations and guidelines which take into account maintenance, prevention and survival

There is a growing interest in nutritional and non-nutritional factors which affect the various stages of life in different ways and how these factors, operative in one stage, have their consequences in later stages. To address these questions has required the command of large and longitudinal data sets about human populations, an understanding of and ability to manipulate gene expression, and the sophistication of detailed food component chemistry. Moreover, it is now clear that there are more fields of food-health relationship than heretofore presumed, such as those that relate to menopause, immune function and cognitive function. Nutritional factors may operate antenatally, in early childhood, during the growth spurt, in the reproductive phase of womanhood, and in much later life. The contextual framework for nutritional thinking is changing in relation to stage of life, including biological as well as chronological age, and in relation to other non-nutritional variables. For example, modest increases in physical activity allow more flexibility in the human diet. Avoidance of substance abuse (tobacco, alcohol, unnecessary medication, meganutrient intakes), allows marked improvements in health in some populations, whilst others continue to be at great risk and require related food intake recommendations. Also of importance throughout life are social, anthropological, economic and educational factors. For example, social activity can stimulate the preferred use of food, and a function of eating is to stimulate social activity-- this interactive bidirectionality between nutritional and non-nutritional factors for health has been appreciated through the modelling of food-health relationships in studies of the aged and cross-culturally. To minimize adverse nutritional effects, a lifespan and contextual approach to nutrition is required.