ABSTRACT Foods containing provitamin A carotenoids are the primary source of vitamin A in many countries,
despite the poor bioavailability of carotenoids. In addition, epidemiologic studies suggest that dietary intake of
carotenoids influences the risk for certain types of cancer, cardiovascular disease and other chronic diseases.
Although it would be ideal to use humans directly to answer critical questions regarding carotenoid absorption,
metabolism and effects on disease progression, appropriate animal models offer many advantages. This paper will
review recent progress in the development of animal models with which to study this class of nutrients. Each
potential model has strengths and weaknesses. Like humans, gerbils, ferrets and preruminant calves all absorb
b-carotene (bC) intact, but only gerbils and calves convert bC to vitamin A with efficiency similar to that of humans.
Mice and rats efficiently convert bC to vitamin A but absorb carotenoids intact only when they are provided in the
diet at supraphysiologic levels. Mice, rats and ferrets can be used to study cancer, whereas primates and gerbils
are probably more appropriate for studies on biomarkers of heart disease. No one animal model completely mimics
human absorption and metabolism of carotenoids; thus the best model must be chosen with consideration of the
specific application being studied, characteristics of the model, and the available funding and facilities. J. Nutr.
129: 2271–2277, 1999.