title: Shifting from a conventional diet to an uncooked vegan diet reversibly alters fecal hydrolytic activities in humans.
abstract: We studied the effect on fecal hydrolytic activities of adopting an uncooked extreme vegan diet and readopting a conventional diet. Eighteen subjects were randomly divided into test and control groups. In the test group subjects adopted the uncooked extreme vegan diet for 1 mo and then resumed a conventional diet for a second month. Controls consumed a conventional diet throughout the study. Phenol and p-cresol concentrations in serum and daily output in urine and fecal enzyme activities were measured. The activity of fecal urease significantly decreased (by 66%) as did cholylglycine hydrolase (55%), beta-glucuronidase (33%) and beta-glucosidase (40%) within 1 wk of beginning the vegan diet. The new level remained throughout the period of consuming this diet. Phenol and p-cresol concentrations in serum and daily outputs in urine significantly declined. The fecal enzyme activities returned to normal values within 2 wk of resuming the conventional diet. Concentrations of phenol and p-cresol in serum and daily output in urine had returned to normal after 1 mo of consuming the conventional diet. No changes were observed in the control group during the study. Results suggest that this uncooked extreme vegan diet causes a decrease in bacterial enzymes and certain toxic products that have been implicated in colon cancer risk.
authors.affiliation: Department of Physiology, University of Kuopio, Finland.
authors.forename: W H
authors.initials: WH
authors.lastname: Ling
authors.forename: O
authors.initials: O
authors.lastname: Hänninen
mesh_terms: D000328:Adult; D000368:Aged; D000581:Amidohydrolases / Q000378:metabolism; D003296:Cooking; D003408:Cresols / Q000097:blood / Q000652:urine; D014676:Diet, Vegetarian; D005243:Feces / Q000201:enzymology*; D005260:Female; D005966:Glucuronidase / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D019800:Phenol; D010636:Phenols / Q000097:blood / Q000652:urine; D014674:Plant Proteins, Dietary / Q000008:administration & dosage / Q000378:metabolism*; D014510:Urease / Q000378:metabolism; D001617:beta-Glucosidase / Q000378:metabolism
chemical_list: D003408:Cresols; D010636:Phenols; D014674:Plant Proteins, Dietary; C032538:4-cresol; D019800:Phenol; D001617:beta-Glucosidase; D005966:Glucuronidase; D000581:Amidohydrolases; C023154:choloylglycine hydrolase; D014510:Urease