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Weekly pizza fortified with 28,000 IU raised Vitamin D by 30 nanograms – RCT Aug 2015

Bioavailability and Safety of Vitamin D3 from Pizza Baked with Fortified Mozzarella Cheese: A Randomized Controlled Trial

Canadian Journal of Dietetic Practice and Research, 2015, 76(3): 109-116, 10.3148/cjdpr-2015-015, Published on the web 17 August 2015.
Banaz Al-Khalidi MSc,a Winnie Chiu MSc,b Dérick Rousseau PhD,c Reinhold Vieth PhDa,d
aDepartment of Nutritional Sciences, University of Toronto, Toronto, ON
bCentre for Hospitality and Culinary Arts, George Brown College, Toronto, ON
cDepartment of Chemistry and Biology, Ryerson University, Toronto, ON
dDepartment of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, ON

Publisher wants $25 for the PDF

Purpose: To assess the bioavailability and safety of vitamin D3 from fortified mozzarella cheese baked on pizza.

Methods: In a randomized, double-blind trial, 96 apparently healthy, ethnically diverse adults were randomized to consume 200 IU or 28,000 IU vitamin D3 fortified mozzarella cheese with pizza once weekly for a total of 8 weeks. Blood and urine samples were collected at baseline (week 1) and final (week 10) visits for serum 25-hydroxyvitamin D and other biochemical measures. The primary outcome compared serum 25-hydroxyvitamin D between groups at 10 weeks. The secondary outcome evaluated the safety of vitamin D dosing protocol as measured by serum and urine calcium, phosphate, creatinine, and serum parathyroid hormone (PTH).

Results: Serum 25-hydroxyvitamin D increased by 5.1 ± 11 nmol/L in the low-dose group (n = 47; P = 0.003), and by 73 ± 22 nmol/L in the high-dose group (n = 49; P < 0.0001). None of the subjects in either group developed any adverse events during the supplementation protocol. Serum PTH significantly decreased in the high-dose group only (P < 0.05).

Conclusions: Vitamin D3 is safe and bioavailable from fortified mozzarella cheese baked on pizza.


  • 1. Whiting SJ, Langlois KA, Vatanparast H, Greene-Finestone LS. 2011. The vitamin D status of Canadians relative to the 2011 Dietary Reference Intakes: an examination in children and adults with and without supplement use. Am J Clin Nutr. 94: 128-135 CrossRef, Medline.
  • 2. Committee to Review Dietary Reference Intakes for Vitamin D and Calcium; Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for calcium and vitamin D. Washington: National Academy Press; 2011 [cited 2015 Feb 02]. Available from: http://books.nap.edu/openbook.php?record_id=13050.
  • 3. Holick MF. 2007. Vitamin D deficiency. New Engl J Med. 357: 266-281 CrossRef, Medline.
  • 4. Gozdzik A, Barta JL, Wu H, Wagner D, Cole DE, Vieth R, . 2008. Low wintertime vitamin D levels in a sample of healthy young adults of diverse ancestry living in the Toronto area: associations with vitamin D intake and skin pigmentation. BMC Public Health. 8: 336 CrossRef, Medline.
  • 5. Gozdzik A, Barta JL, Weir A, Cole DE, Vieth R, Whiting SJ, . 2010. Serum 25-hydroxyvitamin D concentrations fluctuate seasonally in young adults of diverse ancestry living in Toronto. J Nutr. 140: 2213-2220 CrossRef, Medline.
  • 6. Tulchinsky TH, Kaluski DN, Berry EM. 2004. Food fortification and risk group supplementation are vital parts of a comprehensive nutrition policy for prevention of chronic diseases. Eur J Public Health. 14: 226-228 CrossRef, Medline.
  • 7. Health Canada. Food and Drugs Act; Ottawa: Health Canada; 1985.
  • 8. Health Canada. Eating Well with Canada's Food guide; 2011 [cited 2015 Feb 02]. Available from: http://www.hc-sc.gc.ca/fn-an/food-guide-aliment/index-eng.php
  • 9. Vatanparast H, Calvo MS, Green TJ, Whiting SJ. 2010. Despite mandatory fortification of staple foods, vitamin D intakes of Canadian children and adults are inadequate. J Steroid Biochem Mol Biol. 121: 301-303 CrossRef, Medline.
  • 10. Vieth R, Cole DE, Hawker GA, Trang HM, Rubin LA. 2001. Wintertime vitamin D insufficiency is common in young Canadian women. Eur J Clin Nutr. 55: 1091-1097 CrossRef, Medline.
  • 11. Faulkner H, Hussein A, Foran M, Szijarto L. 2000. A survey of vitamin A and D contents of fortified fluid milk in Ontario. J Dairy Sci. 83: 1210-1216 CrossRef, Medline.
  • 12. Whiting SJ, Green TJ, Calvo MS. 2007. Vitamin D intakes in North America and Asia-Pacific countries are not sufficient to prevent vitamin D insufficiency. J Steroid Biochem Mol Biol. 103: 626-630 CrossRef, Medline.
  • 13. Calvo MS, Whiting SJ, Barton CN. 2004. Vitamin D fortification in the United States and Canada: current status and data needs. Am J Clin Nutr. 80: 1710S-1716S Medline.
  • 14. Vesa TH, Marteau P, Korpela R. 2000. Lactose intolerance. J Am Coll Nutr. 19: 165S-175S CrossRef, Medline.
  • 15. Van Horn LV, Bausermann R, Affenito S, Thompson D, Striegel-Moore R, Franko D, . 2011. Ethnic differences in food sources of vitamin D in adolescent American girls: the National Heart, Lung, and Blood Institute Growth and Health Study. Nutr Res. 31: 579-585 CrossRef, Medline.
  • 16. Weiler HA, Leslie WD, Krahn J, Steiman PW, Metge CJ. 2007. Canadian Aboriginal Women have a Higher Prevalence of Vitamin D Deficiency than Non-Aboriginal Women Despite Similar Dietary Vitamin D Intakes. J Nutr. 137: 461-465 Medline.
  • 17. Agriculture and Agri-Food Canada. Canadian Food Trends to 2020: A long range consumer outlook. Edmonton: Serecon Management Consulting Incorporated; 2005.
  • 18. Mehrotra A, Calvo MS, Beelman RB, Levy E, Siuty J, Kalaras MD, . 2014 Aug 13 [cited Feb 02]. Bioavailability of vitamin D2 from enriched mushrooms in prediabetic adults: a randomized controlled trial. Eur J Clin Nutr. 68(10): 1154-1160 [Epub ahead of print]. CrossRef, Medline.
  • 19. Vieth R. In: Feldman D, Glorieux FH, Pike JW, eds. The Pharmacology of Vitamin D, Including Fortification Strategies. Vitamin D. 2nd ed. New York: Academic Press; 2005. p. 995–1015.
  • 20. Wagner D, Rousseau D, Sidhom G, Pouliot M, Audet P, Vieth R. 2008. Vitamin D3 fortification, quantification, and long-term stability in Cheddar and low-fat cheeses. J Agric Food Chem. 56: 7964-7969 CrossRef, Medline.
  • 21. Wagner D, Sidhom G, Whiting SJ, Rousseau D, Vieth R. 2008. The bioavailability of vitamin D from fortified cheeses and supplements is equivalent in adults. J Nutr. 138: 1365-1371 Medline.
  • 22. Natri AM, Salo P, Vikstedt T, Palssa A, Huttunen M, Karkkainen MU, . 2006. Bread fortified with cholecalciferol increases the serum 25-hydroxyvitamin D concentration in women as effectively as a cholecalciferol supplement. J Nutr. 136: 123-127 Medline.
  • 23. Kimball SM, Ursell MR, O'Connor P, Vieth R. 2007. Safety of vitamin D3 in adults with multiple sclerosis. Am J Clin Nutr. 86: 645-651 Medline.
  • 24. Vieth R, Chan PC, MacFarlane GD. 2001. Efficacy and safety of vitamin D3 intake exceeding the lowest observed adverse effect level. Am J Clin Nutr. 73: 288-294 Medline.
  • 25. Heaney RP, Davies KM, Chen TC, Holick MF, Barger-Lux MJ. 2003. Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol. Am J Clin Nutr. 77: 204-210 Medline.