In several studies, the absorption and urinary excretion of free and protein bound Amadori products were measured in rats and humans. Both, in vitro tests with everted intestinal sac preparations and in vivo experiments, showed that there is no active intestinal transport of these compounds but an absorption by diffusion. Trials with tissue slices have shown that there was an uptake into the cells of the liver, kidneys and muscles. Metabolism of Amadori products, if it exists in animals, tends to be very low. Micoorganisms in the large intestines decompose the Amadori products almost completely. The profile of urinary excretion of Amadori products after the ingestion of test meals showed a rapid elimination of the absorbed part, while the fecal output, although low because of the hind gut fermentation, persisted up to 3 days. Only 1-3% of the ingested amounts of protein bound Amadori products were recovered in the urine, which suggests a low absorption rate.