Comparative effects of hydrolizable or condensed tannins on the liver reserve of vitamin A in rats

A 10 weeks study in rats fed a balanced diet containing "hydrosoluble" vitamin A and 3,2 p. 100 by weight of tannic acid resulted in a marked decrease of the hepatic concentration of vitamin A. The same dietary dose of chestnut tree tannins resulted in a much more marked decrease. However, there was no effect of a quebracho extract (condensed tannins) given in the same conditions.