What is a purified diet?
A purified diet uses refined ingredients such as casein, sucrose, cornstarch, and cellulose. These human food grade ingredients have relatively simple chemical compositions (predominantly one nutrient classification) and this feature is important for manipulating individual nutrients for research purposes. Additionally, most refined ingredients contain very limited levels of non-nutrients that could have biological activity. This is in contrast to the natural ingredients (corn, wheat, soybean meal, etc.) used in standard diets, which have relatively complex chemical compositions as well as various phytochemicals that may or may not be physiologically relevant. Refined ingredients are obtained from reliable suppliers of human grade products, and we consistently obtain ingredients from the same vendors, year after year. Additionally, the major protein ingredients are assayed for a specific panel of nutrients to ensure minimal variation. Thus, purified diets will be repeatable and can eas
