This study tested the hypothesis that cholate feeding would counteract the earlier described calcium-induced inhibition of fat digestion. Rats were fed semipurified diets; either low (0.25%, w/w) or high (1.0%) in calcium, the latter diets being without or with 0.5% added sodium cholate. Apparent fat digestibility was 95.6% of intake in the rats fed the low-calcium diet. Calcium feeding significantly lowered apparent fat digestibility to 82.6%, but in the presence of cholate it was 91.2%. It is concluded that the inhibitory effect of calcium on fat digestion is mediated by diminishing the availability of bile acids.