ABSTRACT
This chapter introduces some fundamental and unique considerations of aging research with special reference to nutrition. The scope is limited and includes definitions of aging, special criteria and methodologies for nutrition and aging studies, and the underlying rationale. The use of an age limit will mask the various aging changes that occur at different chronological ages in different individuals. The most meaningful measurement of biological age is physiological or functional age, which also includes the underlying biochemical phenomena. The use of a cross-sectional design in nutritional studies is common in animal nutrition. The difference in findings in mosquito and mouse compared to man may be due to the great heterogeneity of the human subjects compared to the relative genetic and environmental homogeneity of the animal models. Also, rapid changes are under way due to the new development of precise and specific biochemical methods.
