Appropriate animal models for clinical studies.

Results from experiments with animal models can provide useful information relevant to human diet studies. They may indicate approximate levels of supplementation required to see an effect on the end-point measure of interest. They also allow investigation of metabolic responses that require invasive tissue sampling inappropriate for human studies. Animal studies carry the advantages of cost-effectiveness, speed, and control of potential confounding variables. However, results from animal studies cannot be directly extrapolated to clinical trials due to the absence of potential nutrient interactions, environmental stimuli, and learned food preferences and aversions that are experienced by human subjects.