title: Bioavailability of vitamin D₂ from UV-B-irradiated button mushrooms in healthy adults deficient in serum 25-hydroxyvitamin D: a randomized controlled trial.
abstract: OBJECTIVE
  Mushrooms contain very little or any vitamin D(2) but are abundant in ergosterol, which can be converted into vitamin D(2) by ultraviolet (UV) irradiation. Our objective was to investigate the bioavailability of vitamin D(2) from vitamin D(2)-enhanced mushrooms by UV-B in humans, and comparing it with a vitamin D(2) supplement.
  
  
  METHODS
  Fresh mushrooms were irradiated with an UV-B dose of 1.5 J/cm(2), increasing vitamin D(2) content from <1 to 491 μg/100 g and made to an experimental soup. In this 5-week, single-blinded, randomized, placebo-controlled trial, 26 young subjects with serum 25-hydroxyvitamin D (25OHD) ≤ 50 nmol/l were randomly assigned into three groups ((a) mushroom, (b) supplement and (c) placebo). They received during winter (a) 28,000 IU (700 μg) vitamin D(2) via the experimental soup, or (b) 28,000 IU vitamin D(2) via a supplement or (c) placebo, respectively.
  
  
  RESULTS
  After 2 weeks, serum 25OHD was significantly higher in the mushroom than in the placebo group (P=0.001). The serum 25OHD concentrations in the mushroom and supplement groups rose significantly and similarly over the study period by 3.9 nmol/l (95% confidence interval (95% CI): 2.9, 4.8) and by 4.7 nmol/l per week (95% CI: 3.8, 5.7), respectively.
  
  
  CONCLUSIONS
  We are the first to demonstrate in humans that the bioavailability of vitamin D(2) from vitamin D(2)-enhanced button mushrooms via UV-B irradiation was effective in improving vitamin D status and not different to a vitamin D(2) supplement. This trial was registered at http://germanctr.de as DRKS00000195.
authors.affiliation: Department of Haematology/Oncology, Section of Nutrition, University Medical Center Freiburg, Freiburg, Germany. paul.urbain@uniklinik-freiburg.de
authors.forename: P
authors.initials: P
authors.lastname: Urbain
authors.forename: F
authors.initials: F
authors.lastname: Singler
authors.forename: G
authors.initials: G
authors.lastname: Ihorst
authors.forename: H-K
authors.initials: HK
authors.lastname: Biesalski
authors.forename: H
authors.initials: H
authors.lastname: Bertz
mesh_terms: D000328:Adult; D000363:Agaricales / Q000737:chemistry* / Q000528:radiation effects*; D000364:Agaricus / Q000737:chemistry* / Q000528:radiation effects; D001682:Biological Availability; D002118:Calcium / Q000097:blood; D019587:Dietary Supplements; D004872:Ergocalciferols / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies; D016037:Single-Blind Method; D014466:Ultraviolet Rays; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000188:drug therapy; D055815:Young Adult
chemical_list: D004872:Ergocalciferols; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D002118:Calcium