title: Associations between intestinal mucosal function and changes in plasma zinc concentration following zinc supplementation.
abstract: OBJECTIVE
  Subclinical environmental enteropathy is associated with malabsorption of fats, carbohydrates, and vitamins A, B12, and folate; however, little information is available on mineral absorption. We therefore investigated the relation between intestinal mucosal function (measured by the lactulose:mannitol permeability test and plasma citrulline concentration), and zinc (Zn) absorption, as estimated by the change in plasma Zn concentration (PZC) following short-term Zn or placebo supplementation.
  
  
  METHODS
  We conducted a randomized, partially masked, placebo-controlled trial among 282 apparently healthy children 6 to 23 months of age in Burkina Faso. After completing baseline intestinal function tests, participants received either 5 mg Zn, as zinc sulfate, or placebo, daily for 21 days.
  
  
  RESULTS
  At baseline, mean ± standard deviation PZC was 62.9 ± 11.9 μg/dL; median (interquartile range) urinary lactulose:mannitol (L:M) recovery ratio and plasma citrulline concentrations were 0.04 (0.03-0.07) and 11.4 (9.0-15.6) μmol/L, respectively. Change in PZC was significantly greater in the Zn-supplemented versus placebo group (15.6 ± 13.3 vs 0.02 ± 10.9 μg/dL; P < 0.0001), and was negatively associated with initial urinary L:M recovery ratio (-1.1 μg/dL per 50% increase in urinary L:M recovery ratio; P = 0.014); this latter relation did not differ between supplementation groups (P = 0.26). Baseline plasma citrulline concentration was not associated with change in PZC.
  
  
  CONCLUSIONS
  Although altered intestinal permeability may reduce dietary Zn absorption, it likely does not undermine the efficacy of Zn supplementation, given the large increases in PZC following short-term Zn supplementation observed in this study, even among those with increased urinary L:M recovery ratios.
authors.affiliation: Department of Nutrition, University of California, Davis, Davis, CA 95616, USA.
authors.forename: K Ryan
authors.initials: KR
authors.lastname: Wessells
authors.forename: Sonja Y
authors.initials: SY
authors.lastname: Hess
authors.forename: Noel
authors.initials: N
authors.lastname: Rouamba
authors.forename: Zinewendé P
authors.initials: ZP
authors.lastname: Ouédraogo
authors.forename: Mark
authors.initials: M
authors.lastname: Kellogg
authors.forename: Rie
authors.initials: R
authors.lastname: Goto
authors.forename: Christopher
authors.initials: C
authors.lastname: Duggan
authors.forename: Jean-Bosco
authors.initials: JB
authors.lastname: Ouédraogo
authors.forename: Kenneth H
authors.initials: KH
authors.lastname: Brown
mesh_terms: D000293:Adolescent; D000328:Adult; D002050:Burkina Faso; D002648:Child; D002956:Citrulline / Q000097:blood; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007408:Intestinal Absorption; D007413:Intestinal Mucosa / Q000378:metabolism* / Q000473:pathology; D007792:Lactulose / Q000652:urine; D008286:Malabsorption Syndromes / Q000097:blood*; D008297:Male; D008353:Mannitol / Q000652:urine; D010539:Permeability; D012016:Reference Values; D055815:Young Adult; D015032:Zinc / Q000097:blood* / Q000378:metabolism; D019287:Zinc Sulfate / Q000008:administration & dosage / Q000378:metabolism
chemical_list: D002956:Citrulline; D008353:Mannitol; D007792:Lactulose; D019287:Zinc Sulfate; D015032:Zinc