Vitamin D and Food Fortification

Vitamin D: Health, Disease and Therapeutics, Fourth Edition: Volume 2

Volumn 2, Issue , 2017, Pages 109-127

  Cashman, Kevin D ^a   Kiely, Mairead ^a  

^a UNIVERSITY COLLEGE CORK   (Ireland)

Author keywords

25 Hydroxyvitamin D; Biofortification; Cholecalciferol; Dietary modeling; Ergocalciferol; Food fortification; Vitamin D; Vitamin D intakes; Vitamin D recommendations; Vitamin D status

Indexed keywords

EID: 85050150004     PISSN: None     EISSN: None     Source Type: Book    
DOI: 10.1016/B978-0-12-809963-6.00063-8     Document Type: Chapter

References (93)

1. A. Cranney, T. Horsley, S. O’Donnell, H. Weiler, L. Puil, D. Ooi, S. Atkinson, L. Ward, D. Moher, D. Hanley, M. Fang, F. Yazdi, C. Garritty, M. Sampson, N. Barrowman, A. Tsertsvadze and V. Mamaladze (2007) Effectiveness and safety of vitamin D in relation to bone health. Rockville (MD): Agency for Healthcare Research and Quality Evidence Report/Technology Assessment No. 158
2. M.F. Holick, N.C. Binkley, H.A. Bischoff-Ferrari, C.M. Gordon, D.A. Hanley, R.P. Heaney, M.H. Murad and C.M. Weaver (2011) Evaluation, treatment, and prevention of vitamin D deficiency: an endocrine society clinical practice guideline. J Clin Endocrinol Metab 96 1911-1930.
3. K.D. Cashman and M. Kiely (2011) Towards prevention of vitamin D deficiency and beyond: knowledge gaps and research needs in vitamin D nutrition and public health. Br J Nutr 106(11), 1617-1627.
4. R.L. Schleicher, M.R. Sternberg, A.C. Looker, E.A. Yetley, D.A. Lacher, C.T. Sempos, C.L. Taylor, R.A. Durazo-Arvizu, K.L. Maw, M. Chaudhary-Webb, C.L. Johnson and C.M. Pfeiffer (2016) National estimates of serum total 25-hydroxyvitamin D and metabolite concentrations measured by liquid chromatography-tandem mass spectrometry in the US Population during 2007–2010. J Nutr 146 1051-1061.
5. K. Sarafin, R. Durazo-Arvizu, L. Tian, K.W. Phinney, S. Tai, J.E. Camara, J. Merkel, E. Green, C.T. Sempos and S.P. Brooks (2015) Standardizing 25-hydroxyvitamin D values from the Canadian health measures survey. Am J Clin Nutr 102 1044-1050.
6. K.D. Cashman, K.G. Dowling, Z. Škrabáková, M. Gonzalez-Gross, J. Valtueña, S. De Henauw, L. Moreno, C.T. Damsgaard, K.F. Michaelsen, C. Mølgaard, R. Jorde, G. Grimnes, G. Moschonis, C. Mavrogianni, Y. Manios, M. Thamm, G.B. Mensink, M. Rabenberg, M.A. Busch, L. Cox, S. Meadows, G. Goldberg, A. Prentice, J.M. Dekker, G. Nijpels, S. Pilz, K.M. Swart, N.M. van Schoor, P. Lips, G. Eiriksdottir, V. Gudnason, M.F. Cotch, S. Koskinen, C. Lamberg-Allardt, R.A. Durazo-Arvizu, C.T. Sempos and M. Kiely (2016) Vitamin D deficiency in Europe – pandemic? Am J Clin Nutr 103(4), 1033-1044.
7. Scientific Advisory Committee on Nutrition. Report on vitamin D and health. Available from: http://www.sacn.gov.uk/pdfs/sacn_vitamin D_and_health_report_web.pdf 2016.
8. Institute of Medicine (2011) Dietary reference intakes for calcium and vitamin D. Washington (DC): The National Academies Press
9. German Nutrition Society (2012) New reference values for vitamin D. Ann Nutr Metab 60 241-246.
10. NORDEN nordic nutrition recommendations 5th ed. Available from: http://www.slv.se/en-gb/Startpage-NNR/Public-consultation11/ (NNR5) – Vitamin D
11. EFSA NDA Panel (EFSA Panel on Dietetic Products, Nutrition and Allergies) (2016) Scientific opinion on dietary reference values for vitamin D. EFSA J 10.2903/j.efsa.2016
12. A.R. Webb (2006) Who, what, where and when-influences on cutaneous vitamin D synthesis. Prog Biophys Mol Biol 92(1), 17-25.
13. M.F. Holick (2008) Deficiency of sunlight and vitamin D. BMJ 336 1318-1319.
14. M. Kiely and L.J. Black (2012) Dietary strategies to maintain adequacy of circulating 25-hydroxyvitamin D concentrations. Scand J Clin Lab Invest Suppl 243 14-23.
15. K.M. Seamans and K.D. Cashman (2009) Existing and potentially novel functional markers of vitamin D status: a systematic review. Am J Clin Nutr 89(6), 1997S-2008S.
16. S.J. Whiting, J.P. Bonjour, F.D. Payen and B. Rousseau (2015) Moderate amounts of vitamin D3 in supplements are effective in raising serum 25-hydroxyvitamin D from low baseline levels in adults: a systematic review. Nutrients 7(4), 2311-2323.
17. S.J. Whiting, K.A. Langlois, Vatanparast and L.S. Greene-Finestone (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.
18. V.L. Fulgoni, D.R. Keast, R.L. Bailey and J. Dwyer (2011) Foods, fortificants, and supplements: where do Americans get their nutrients? J Nutr 141 1-8.
19. L.J. Black, J. Walton, A. Flynn, K.D. Cashman and M. Kiely (2015) Small increments in vitamin D intake by Irish adults over a decade show that strategic initiatives to fortify the food supply are needed. J Nutr 145(5), 969-976.
20. R.L. Bailey, K.W. Dodd, J.A. Goldman, J.J. Gahche, J.T. Dwyer, A.J. Moshfegh, C.T. Sempos and M.F. Picciano (2010) Estimation of total usual calcium and vitamin D intakes in the United States. J Nutr 140 817-822.
21. K.M. Sanders, A.L. Stuart, E.J. Williamson, J.A. Simpson, M.A. Kotowicz, D. Young and G.C. Nicholson (2010) Annual high-dose oral vitamin D and falls and fractures in older women: a randomized controlled trial. JAMA 303 1815-1822.
22. K.D. Cashman and M. Kiely (2016) Tackling inadequate vitamin D intakes within the population: fortification of dairy products with vitamin D may not be enough. Endocrine 51 38-46.
23. M.S. Calvo and S.J. Whiting (2006) Public health strategies to overcome barriers to optimal vitamin D status in populations with special needs. J Nutr 136 1135-1139.
24. C. Lamberg-Allardt (2006) Vitamin D in foods and as supplements. Prog Biophys Mol Biol 92 33-38.
25. I. Elmadfa, A. Meyer, V. Nowak, V. Hasenegger, P. Putz, R. Verstraeten, A.M. Remaut-DeWinter, P. Kolsteren, J. Dostálová, P. Dlouhý, E. Trolle, S. Fagt, A. Biltoft-Jensen, J. Mathiessen, M. Velsing Groth, L. Kambek, N. Gluskova, S. Voutilainen, A. Erkkilä, M. Vernay, C. Krems, A. Strassburg, A.L. Vasquez-Caicedo, C. Urban, A. Naska, E. Efstathopoulou, E. Oikonomou, K. Tsiotas, V. Bountziouka, V. Benetou, A. Trichopoulou, G. Zajkás, V. Kovács, E. Martos, P. Heavey, C. Kelleher, J. Kennedy, A. Turrini, G. Selga, M. Sauka, J. Petkeviciene, J. Klumbiene, T. Holm Totland, L.F. Andersen, E. Halicka, K. Rejman, B. Kowrygo, S. Rodrigues, S. Pinhão, L.S. Ferreira, C. Lopes, E. Ramos, M.D. Vaz Almeida, M. Vlad, M. Simcic, K. Podgrajsek, L. Serra Majem, B. Román Viñas, J. Ngo, L. Ribas Barba, W. Becker, H. Fransen, B. Van Rossum, M. Ocké, B. Margetts, A. Rütten, K. Abu-Omar, P. Gelius and A. Cattaneo (2009) European nutrition and health report. Ann Nutr Metab 55 1-40.
26. H. Vatanparast, M.S. Calvo, T.J. Green and S.J. Whiting (2010) Despite mandatory fortification of staple foods, vitamin D intakes of Canadian children and adults are inadequate. J Steroid Biochem Mol Biol 121(1–2), 301-303.
27. B. Roman Vinas, L. Ribas Barba, J. Ngo, M. Gurinovic, R. Novakovic, A. Cavelaars, L.C. de Groot, P. van’t Veer, C. Matthys and L. Serra Majem (2011) Projected prevalence of inadequate nutrient intakes in Europe. Ann Nutr Metab 59 84-95.
28. Y.A. Shakur, W. Lou and M.R. L’Abbe (2014) Examining the effects of increased vitamin D fortification on dietary inadequacy in Canada. Can J Public Health 105 127-132.
29. K.D. Cashman (2015) Vitamin D. Dietary requirements and food fortification as a means of helping achieve adequate vitamin D status. J Steroid Biochem Mol Biol 148 19-26.
30. M.S. Calvo, S.J. Whiting and C.N. Barton (2004) Vitamin D fortification in the United States and Canada: current status and data needs. Am J Clin Nutr 80(6), 1710S-1716S.
31. M.S. Calvo and S.J. Whiting (2013) Survey of current vitamin D food fortification practices in the United States and Canada. J Steroid Biochem Mol Biol 136 211-213.
32. Health Canada. Consolidation of the food and drugs act and the food and drug regulations. Available from: http://publications.gc.ca/site/eng/117118/publication.html.
33. Health Canada. Food & Drug Act B. 08.003. Available from: http://laws-lois.justice.gc.ca/eng/regulations/c.r.c.,_c._870/page-87.html.
34. Health Canada. Interim marketing authorization. Available from: http://www.hc-sc.gc.ca/fn-an/legislation/ima-amp/plant_based_beverages-boissons_vegetales-eng.php.
35. Health Canada. Food & drug act B. 01.404. Available from: http://laws-lois.justice.gc.ca/eng/regulations/c.r.c.,_c._870/page-34.html#h-23.
36. Health Canada. Food & drug act B. 09.016. Available from: http://laws-lois.justice.gc.ca/eng/regulations/C.R.C.,_c._870/section-B.09.016–20111027.html.
37. K. Langlois, L. Greene-Finestone, J. Little, N. Hidiroglou and S. Whiting (2011) Vitamin D status of Canadians as measured in the 2007 to 2009. Canadian health measures survey. Health Rep 21 47-55.
38. US Food and Drug Administration. Direct food substances affirmed as generally recognized as safe. Subpart B. Listing of specific substances affirmed as GRAS. Sec 184.1950 vitamin D. Available from: http://www.accessdata.fda.gov/scripts/cdrh/cfcfr/CFRSearch.cfm?fr_184.1950.
39. US Food and Drug Administration (Monday, July 18, 2016) Food additives permitted for direct addition to food for human consumption; vitamin D2 and vitamin D3. Fed Regist 81(137), http://regulations.justia.com/regulations/fedreg/2016/07/18/2016-16738.html Available from
40. E.A. Yetley (2008) Assessing the vitamin D status of the US population. Am J Clin Nutr 88 558S-564S.
41. M.S. Calvo (2000) Dietary considerations to prevent loss of bone and renal function. Nutrition 16 564-566.
42. F.A. Tylavsky, S. Cheng, A. Lyytikainen, H. Viljakainen and C. Lamberg-Allardt (2006) Strategies to improve vitamin D status in northern European children: exploring the merits of vitamin D fortification and supplementation. J Nutr 136 1130-1134.
43. I.T. Laaksi, J.P. Ruohola, T.J. Ylikomi, A. Auvinen, R.I. Haataja, H.K. Pihlajamäki and P.J. Tuohimaa (2006) Vitamin D fortification as public health policy: significant improvement in vitamin D status in young Finnish men. Eur J Clin Nutr 60 1035-1038.
44. T. Piirainen, K. Laitinen and E. Isolauri (2007) Impact of national fortification of fluid milks and margarines with vitamin D on dietary intake and serum 25-hydroxyvitamin D concentration in 4-year-old children. Eur J Clin Nutr 61 123-128.
45. M. Lehtonen-Veromaa, T. Mottonen, A. Leino, O.J. Heinonen, E. Rautava and J. Viikari (2008) Prospective study on food fortification with vitamin D among adolescent females in Finland: minor effects. Br J Nutr 100 418-423.
46. C. Lamberg-Allardt, M. Brustad, H.E. Meyer and L. Steingrimsdottir (2013) Vitamin D – a systematic literature review for the 5th edition of the nordic nutrition recommendations. Food Nutr Res 3 57.
47. A. Helldán, S. Raulio, M. Kosola, H. Tapanainen, M.-L. Ovaskainen and S. Virtanen (2012) The national FINDIET 2012 survey. ISBN 978-952-245-950-3 (painettu); 978-952-245-951-0 (verkko) THL. Raportti 16/2013, 187 s. Helsinki 2013
48. L.J. Black, K.M. Seamans, K.D. Cashman and M. Kiely (2012) An updated systematic review and meta-analysis of the efficacy of vitamin D food fortification. J Nutr 142(6), 1102-1108.
49. S. O’Donnell, A. Cranney, T. Horsley, H.A. Weiler, S.A. Atkinson, D.A. Hanley, D.S. Ooi, L. Ward, N. Barrowman, M. Fang, M. Sampson, A. Tsertsvadze and F. Yazdi (2008) Efficacy of food fortification on serum 25-hydroxyvitamin D concentrations: systematic review. Am J Clin Nutr 88 1528-1534.
50. Y. Manios, G. Moschonis, C. Mavrogianni, E. van den Heuvel, C.M. Singh-Povel, M. Kiely and K.D. Cashman (July 22, 2016) Reduced-fat Gouda-type cheese enriched with vitamin D3 effectively prevents vitamin D deficiency during winter months in postmenopausal women in Greece. Eur J Nutr [Epub ahead of print] PubMed PMID: 27449925
51. S.A. Kazmi, R. Vieth and D. Rousseau (2007) Vitamin D3 fortification and quantification in processed dairy products. Int Dairy J 17 753-759.
52. J. El-Hayek, T.T. Pham, S. Finch, T.J. Hazell, S. Jean-Philippe, C.A. Vanstone, S. Agellon, C. Rodd, F. Rauch and H.A. Weiler (2013) Vitamin D status in montreal preschoolers is satisfactory despite low vitamin D intake. J Nutr 143 154-160.
53. National Diet and Nutrition Survey (NDNS) rolling program. Available from: https://www.gov.uk/government/statistics/national-diet-and-nutrition-survey-results-from-years-1-to-4-combined-of-the-rolling-programme-for-2008-and-2009-to-2011-and-2012.
54. A. Flynn, T. Hirvonen, G.B. Mensink, M.C. Ocké, L. Serra-Majem, K. Stos, L. Szponar, I. Tetens, A. Turrini, R. Fletcher and T. Wildemann (2009) Intake of selected nutrients from foods, from fortification and from supplements in various European countries. Food Nutr Res 10.3402/fnr.v53i0.2038
55. U.S. Babu and M.S. Calvo (2010) Modern India and the vitamin D dilemma: evidence for the need of a national food fortification program. Mol Nutr Food Res 54 1134-1147.
56. K.H. Madsen, L.B. Rasmussen, R. Andersen, C. Mølgaard, J. Jakobsen, P.J. Bjerrum, E.W. Andersen, H. Mejborn and I. Tetens (2013) Randomized controlled trial of the effects of vitamin D–fortified milk and bread on serum 25-hydroxyvitamin D concentrations in families in Denmark during winter: the Vitamin D study. Am J Clin Nutr 98 374-382.
57. R.E. Allen, A.D. Dangour, A.E. Tedstone and Z. Chalabi (2015) Does fortification of staple foods improve vitamin D intakes and status of groups at risk of deficiency? A United Kingdom modeling study. Am J Clin Nutr 102 338-344.
58. K.D. Cashman (2012) The role of vitamers and dietary-based metabolites of vitamin D in prevention of vitamin D deficiency. Food Nutr Res 56. 10.3402/fnr.v56i0.5383
59. L. Tripkovic, H. Lambert, K. Hart, C.P. Smith, G. Bucca, S. Penson, G. Chope, E. Hyppönen, J. Berry, R. Vieth and S. Lanham-New (June 2012) Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis. Am J Clin Nutr 95(6), 1357-1364.
60. P. Autier, S. Gandini and P. Mullie (August 2012) A systematic review: influence of vitamin D supplementation on serum 25-hydroxyvitamin D concentration. J Clin Endocrinol Metab 97(8), 2606-2613.
61. L.A. Houghton and R. Vieth (2006) The case against ergocalciferol (vitamin D2) as a vitamin supplement. Am J Clin Nutr 84 694-697.
62. V.F. Logan, A.R. Gray, M.C. Peddie, M.J. Harper and L.A. Houghton (March 28, 2013) Long-term vitamin D3 supplementation is more effective than vitamin D2 in maintaining serum 25-hydroxyvitamin D status over the winter months. Br J Nutr 109(6), 1082-1088.
63. L. Ovesen, C. Brot and J. Jakobsen (2003) Food contents and biological activity of 25-hydroxyvitamin D: a vitamin D metabolite to be reckoned with? Ann Nutr Metab 47 107-113.
64. Food Standards Agency, UK (2008) McCance and Widdowson’s composition of foods integrated dataset. http://www.food.gov.uk/science/dietarysurveys/dietsurveys/
65. E. Saxholt, A.T. Christensen, A. Møller, H.B. Hartkopp, K. Hess Ygil and O.H. Hels (2008) Danish food composition databank, revision 7. Department of Nutrition, National Food Institute, Technical University of Denmark http://www.foodcomp.dk/ Available from
66. Federal Food Safety, Veterinary Office (FSVO) (2015) Swiss food composition database. V5.2. http://naehrwertdaten.ch/request?xml=MessageData&xml=MetaData&xsl=Start&lan=en&pageKey=Start Available from
67. US Department of Agriculture, Agricultural Research Service. USDA national nutrient database for standard reference, release 28. Nutrient Data Laboratory Home Page. Available from: http://ndb.nal.usda.gov/ndb/foods/show/112.
68. C.L. Taylor, K.Y. Patterson, J.M. Roseland, S.A. Wise, J.M. Merkel, P.R. Pehrsson and E.A. Yetley (May 2014) Including food 25-hydroxyvitamin D in intake estimates may reduce the discrepancy between dietary and serum measures of vitamin D status. J Nutr 144(5), 654-659.
69. R.P. Heaney, L.A. Armas and C. French (May 2013) All-source basal vitamin D inputs are greater than previously thought and cutaneous inputs are smaller. J Nutr 143(5), 571-575.
70. K.D. Cashman, K.M. Seamans, A.J. Lucey, E. Stöcklin, P. Weber, M. Kiely and T.R. Hill (2012) Relative effectiveness of oral 25-hydroxyvitamin D3 and vitamin D3 in raising wintertime serum 25-hydroxyvitamin D in older adults. Am J Clin Nutr 95 1350-1356.
71. Panel on Additives, Products or Substances used in Animal Feed (2005) Opinion of the scientific panel on additives and products or substances used in animal feed on a request from the commission on the evaluation of safety and efficacy of “HyD” (calcifediol), based on 25-hydroxylcholecalciferol/25-hydroxy-pre-cholecalciferol, as feed additive in accordance with council directive 70/524/EEC. EFSA J 224 1-35.
72. Food, Drug Administration (March 16, 2007) Food substances affirmed as generally recognized as safe in feed and drinking water of animals: 25-hydroxyvitamin D3 Federal Register vol. 72, Number 51
73. European Food Safety Authority (2012) Scientific opinion on the tolerable upper intake level of vitamin D. EFSA J 10 2813.
74. L.V. Van Horn, R. Bausermann, S. Affenito, D. Thompson, R. Striegel-Moore, D. Franko and A. Albertson (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.
75. P. Mattila, K. Lehikoinen, T. Kiiskinen and V. Piironen (1999) Cholecalciferol and 25-hydroxycholecalciferol content of chicken egg yolk as affected by the cholecalciferol content of feed. J Agric Food Chem 47 4089-4092.
76. P. Mattila, T. Rokka, K. Konko, P. Mattila, T. Rokka and K. Konko (2003) Effect of cholecalciferol-enriched hen feed on egg quality. J Agric Food Chem 51 283-287.
77. P. Mattila, J. Valaja, L. Rossow, E. Venäläinen and T. Tupasela (2004) Effect of vitamin D2- and D3-enriched diets on egg vitamin D content, production, and bird condition during an entire production period. Poult Sci 83 433-440.
78. P.H. Mattila, E. Valkonen and J. Valaja (2011) Effect of different vitamin D supplementations in poultry feed on vitamin D content of eggs and chicken meat. J Agric Food Chem 59 8298-8303.
79. L. Yao, T. Wang, M. Persia, R.L. Horst and M. Higgins (2013) Effects of vitamin D3-enriched diet on egg yolk vitamin D3 content and yolk quality. J Food Sci 78 C178-C183.
80. L.C. Browning and A.J. Cowieson (2014) Vitamin D fortification of eggs for human health. J Sci Food Agric 94 1389-1396.
81. Commission of the European Communities (2003) European union register of feed additives pursuant to regulation (EC) No 1831/2003. http://ec.europa.eu/food/food/animalnutrition/feedadditives/update.pdf Available from
82. A. Hayes, S. Duffy, M. O’Grady, J. Jakobsen, K. Galvin, J. Teahan-Dillon, J. Kerry, A. Kelly, J. O’Doherty, S. Higgins, K.M. Seamans and K.D. Cashman (August 3, 2016) Vitamin D-enhanced eggs are protective of wintertime serum 25-hydroxyvitamin D in a randomized controlled trial of adults. Am J Clin Nutr pii: ajcn132530. [Epub ahead of print]
83. R.M. Krauss, R.H. Eckel, B. Howard, L.J. Appel, S.R. Daniels, R.J. Deckelbaum, J.W. Erdman Jr., P. Kris-Etherton, I.J. Goldberg, T.A. Kotchen, A.H. Lichtenstein, W.E. Mitch, R. Mullis, K. Robinson, J. Wylie-Rosett, S. St Jeor, J. Suttie, D.L. Tribble and T.L. Bazzarre AHA Dietary Guidelines Revision (2000) A statement for healthcare professionals from the nutrition committee of the American Heart Association. Stroke 31 2715-2766.
84. S.T. Itkonen, E. Skaffari, P. Saaristo, E.M. Saarnio, M. Erkkola, J. Jakobsen, K.D. Cashman and C. Lamberg-Allardt (2016) Effects of vitamin D2-fortified bread v. supplementation with vitamin D2 or D3 on serum 25-hydroxyvitamin D metabolites: an 8-weerandomised-controlled trial in young adult Finnish women. Br J Nutr 115 1232-1239.
85. EFSA NDA Panel (EFSA panel on dietetic products, nutrition and allergies) (2015) Scientific opinion on the safety of UV-treated bread as a novel food. EFSA J 13(7), 4148. 10.2903/j.efsa.2017.4962 2015.4148 16 pp.
86. K.D. Cashman, M. Kiely, K.M. Seamans and P. Urbain (2016) Effect of ultraviolet light-exposed mushrooms on vitamin D status: liquid chromatography-tandem mass spectrometry reanalysis of bio banked sera from a randomized controlled trial and a systematic review plus meta-analysis. J Nutr 146 565-575.
87. EFSA NDA Panel (EFSA panel on dietetic products, nutrition and allergies) (2016) Scientific opinion on the safety of UV-treated milk as a novel food pursuant to Regulation (EC) No 258/97. EFSA J 14 4370. 10.2903/j.efsa.2016.4370
88. S.S. Harris and B. Dawson-Hughes (2002) Plasma vitamin D and 25(OH)D responses of young and old men to supplementation with vitamin D3. J Am Coll Nutr 21 357-362.
89. H.T. Viljakainen, A. Palssa, M. Kärkkäinen, J. Jakobsen and C. Lamberg-Allardt (2006) How much vitamin D3 do the elderly need? J Am Coll Nutr 25 429-435.
90. R. Vieth (1999) Vitamin D supplementation, 25-hydroxyvitamin D concentrations, and safety. Am J Clin Nutr 69 842-856.
91. IARC (International Agency for Research on Cancer) (2008) Vitamin D and cancer. IARC working group reports vol. 5 Lyon: International Agency for Research on Cancer
92. P.M. Brannon (2012) Key questions in vitamin D research. Scand J Clin Lab Invest Suppl 243 154-162.
93. S. Gallo, K. Comeau, C. Vanstone, S. Agellon, A. Sharma, G. Jones, M. L’Abbé, A. Khamessan, C. Rodd and H. Weiler (2013) Effect of different dosages of oral vitamin D supplementation on vitamin D status in healthy, breastfed infants: a randomized trial. JAMA 309(17), 1785-1792.