Use of in vivo kinetic techniques to evaluate metabolism of nutrients.

Most nutrition research is related to rates of physiological processes. Information about those processes can be gained by in vivo kinetic techniques; however, many nutritionists are hesitant to use in vivo kinetics. The two basic in vivo kinetic techniques are single injection and continuous infusion of tracer into a pool of tracee. Either technique can form the basis for multiple-pool kinetics, or modeling. Solving a multiple-pool system can provide flow rates of substances between metabolic pools and is valuable for understanding a particular metabolic pathway or process. In vivo kinetic techniques can be valuable in understanding mechanisms whereby partitioning agents affect the distribution of nutrients, especially protein and fat, in food-producing animals. In vivo kinetics is a valuable tool for nutrition research and should be used more frequently.