Further, other factors should be considered, such as the lower (negligible) cholesterol esterase activity of commercially available (pig) enzymes [42], intestinal mucosal abnormalities, lower alkaline duodenal pH, changed bile salt profile or small intestinal bacterial overgrowth, which are present in a significant percentage (35–37%) of CF patients [45,46,47,48,49]. This evidence concerns the gene CEL and cystic fibrosis.