Human intestinal specificity toward dietary sterols studied by balance methods

Human intestinal specificity toward sterols was studied by a balance method in 10 hyperlipoproteinemic patients fed plant sterol mixture with chromium sesquioxide as fecal flow marker. The mean fecal recovery of campesterol (C28) was 20% less than that of beta-sitosterol (C29). This difference persisted when corrected for fecal flow (by marker recovery), indicating differences in their intestinal uptake (C28 greater than C29). The ratio of fecal cholesterol to its 5beta-reduction products was lower than that of beta-sitosterol in all patients; in vitro, 5beta-reduction of both sterols was similar. The recovery of sterols from patients was unrelated to their 5beta-reduction in the intestine.