title: Both free and esterified plant sterols reduce cholesterol absorption and the bioavailability of beta-carotene and alpha-tocopherol in normocholesterolemic humans.
abstract: BACKGROUND
  Plant sterols reduce cholesterol absorption, which leads to a decrease in plasma and LDL-cholesterol concentrations. Plant sterols also lower plasma concentrations of carotenoids and alpha-tocopherol, but the mechanism of action is not yet understood.
  
  
  OBJECTIVE
  The aims of this clinical study were to determine whether plant sterols affect the bioavailability of beta-carotene and alpha-tocopherol in normocholesterolemic men and to compare the effects of plant sterol esters and plant free sterols on cholesterol absorption.
  
  
  METHODS
  Twenty-six normocholesterolemic men completed the double-blind, randomized, crossover study. Subjects consumed daily, for 1 wk, each of the following 3 supplements: a low-fat milk-based beverage alone (control) or the same beverage supplemented with 2.2 g plant sterol equivalents provided as either free sterols or sterol esters. During this 1-wk supplementation period, subjects consumed a standardized diet.
  
  
  RESULTS
  Both of the milks enriched with plant sterols induced a similar (60%) decrease in cholesterol absorption. Plant free sterols and plant sterol esters reduced the bioavailability of beta-carotene by approximately 50% and that of alpha-tocopherol by approximately 20%. The reduction in beta-carotene bioavailability was significantly less with plant free sterols than with plant sterol esters. At the limit of significance (P = 0.054) in the area under the curve, the reduction in alpha-tocopherol bioavailability was also less with plant free sterols than with plant sterol esters.
  
  
  CONCLUSIONS
  Both plant sterols reduced beta-carotene and alpha-tocopherol bioavailability and cholesterol absorption in normocholesterolemic men. However, plant sterol esters reduced the bioavailability of beta-carotene and alpha-tocopherol more than did plant free sterols.
authors.affiliation: Nestlé Research Center, Nestec Ltd, Lausanne, Switzerland. myriam.richelle@rdls.nestle.com
authors.forename: Myriam
authors.initials: M
authors.lastname: Richelle
authors.forename: Marc
authors.initials: M
authors.lastname: Enslen
authors.forename: Corinne
authors.initials: C
authors.lastname: Hager
authors.forename: Michel
authors.initials: M
authors.lastname: Groux
authors.forename: Isabelle
authors.initials: I
authors.lastname: Tavazzi
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Godin
authors.forename: Alvin
authors.initials: A
authors.lastname: Berger
authors.forename: Sylviane
authors.initials: S
authors.lastname: Métairon
authors.forename: Sylvie
authors.initials: S
authors.lastname: Quaile
authors.forename: Christelle
authors.initials: C
authors.lastname: Piguet-Welsch
authors.forename: Laurent
authors.initials: L
authors.lastname: Sagalowicz
authors.forename: Hilary
authors.initials: H
authors.lastname: Green
authors.forename: Laurent Bernard
authors.initials: LB
authors.lastname: Fay
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000493:pharmacokinetics; D019540:Area Under Curve; D001682:Biological Availability; D002784:Cholesterol / Q000097:blood* / Q000493:pharmacokinetics*; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D018592:Cross-Over Studies; D004224:Diterpenes; D004311:Double-Blind Method; D004952:Esters; D006801:Humans; D007408:Intestinal Absorption; D008297:Male; D010840:Phytosterols / Q000494:pharmacology*; D000084562:Retinyl Esters; D014801:Vitamin A / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D024502:alpha-Tocopherol / Q000493:pharmacokinetics*; D019207:beta Carotene / Q000493:pharmacokinetics*
chemical_list: D000975:Antioxidants; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D004224:Diterpenes; D004952:Esters; D010840:Phytosterols; D000084562:Retinyl Esters; D019207:beta Carotene; D014801:Vitamin A; C014794:retinol palmitate; D002784:Cholesterol; D024502:alpha-Tocopherol