Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-19T02:42:27.948Z Has data issue: false hasContentIssue false

Geographical differences in vitamin D status, with particular reference to European countries

Published online by Cambridge University Press:  07 March 2007

Rikke Andersen
Affiliation:
Institute of Food Safety and Nutrition, The Danish Veterinary and Food Administration, 30A Sydmarken, 2860 Søborg, Denmark
Jette Jakobsen
Affiliation:
Institute of Food Safety and Nutrition, The Danish Veterinary and Food Administration, 30A Sydmarken, 2860 Søborg, Denmark
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Vitamin D is produced endogenously when the skin is exposed to sunlight and can be obtained exogenously from a few natural food sources, from food fortification and from supplements. Generally, vitamin D intake is low ≤2–3 μg/d in Europe. Casual exposure to sunlight is thought to provide most of the vitamin D requirement of the human population. However, skin synthesis of vitamin D may not compensate for the low nutritional intake in Europe, even in countries with high supplies from food fortification and supplements. For assessment of vitamin D nutritional status the concentration of 25-hydroxyvitamin D (25(OH)D) in serum is considered to be an accurate integrative measure reflecting an individual's dietary intake and cutaneous production. A substantial percentage of the elderly and adolescents in Europe have a low concentration of 25(OH)D; in the elderly this percentage ranges from approximately 10 in the Nordic countries to approximately 40 in France. Low vitamin D status seems to be aggravated by disease and immobility, and by a low frequency of supplement use.

Type
Symposium on ‘Optimal nutrition for osteoporosis prevention’
Copyright
Copyright © The Nutrition Society 2003

References

Aloia, JF, Cohn, SH, Vaswani, A, Yeh, JK, Yuen, K & Ellis, K (1985) Risk factors for postmenopausal osteoporosis. American Journal of Medicine 78, 95100.CrossRefGoogle ScholarPubMed
Bates, CJ, Carter, GD, Mishra, GD, O'Shea, D, Jones, J & Prentice, A (2003) In a population study, can parathyroid hormone aid the definition of adequate vitamin D status? A study of people aged 65 years and over from the British National Diet and Nutrition Survey. Osteoporosis International 4, 152159.CrossRefGoogle Scholar
Bates, CJ, Prentice, A, Cole, TJ, van der Pols, JC, Doyle, W, Finch, S, Smithers, G & Clarke, PC (1999) Micronutrients: highlights and research challenges from the 1994–5 National Diet and Nutrition Survey of people aged 65 years and over. British Journal of Nutrition 82, 715.CrossRefGoogle ScholarPubMed
Becker, W & Pearson, M (2002) Kostvanor och naringsintag i Sverige. ( Dietary Habits and Nutrient Intake in Sweden ) Uppsala, Sweden: Statens Livsmedelsverket.Google Scholar
Bettica, P, Bevilacqua, M, Vago, T & Norbiato, G (1999) High prevalence of hypovitaminosis D among free-living postmenopausal women referred to an osteoporosis outpatient clinic in northern Italy for initial screening. Osteoporosis International 9, 226229.CrossRefGoogle Scholar
Boonen, S, Vanderschueren, D, Cheng, XG, Verbeke, G, Dequeker, J, Geusens, P, Broos, P & Bouillon, R (1997) Age-related (type II) femoral neck osteoporosis in men: biochemical evidence for both hypovitaminosis D-and androgen deficiency-induced bone resorption. Journal of Bone and Mineral Research 12, 21192126.CrossRefGoogle ScholarPubMed
Brot, C, Vestergaard, P, Kolthoff, N, Gram, J, Hermann, AP & Sørensen, OH (2001) Vitamin D status and its adequacy in healthy Danish perimenopausal women: relationships to dietary intake, sun exposure and serum parathyroid hormone. British Journal of Nutrition 86, Suppl. 1. S97S103.CrossRefGoogle ScholarPubMed
Burnand, B, Sloutskis, D, Gianoli, F, Cornuz, J, Rickenbach, M, Paccaud, F & Burckhardt, P (1992) Serum 25-hydroxyvitamin D: distribution and determinants in the Swiss population. American Journal of Clinical Nutrition 56, 537542.CrossRefGoogle ScholarPubMed
Carnevale, V, Modoni, S, Pileri, M, Di Giorgio, A, Chiodini, I, Minisola, S, Vieth, R & Scillitani, A (2001) Longitudinal evaluation of vitamin D status in healthy subjects from southern Italy: seasonal and gender differences. Osteoporosis International 12, 10261030.CrossRefGoogle ScholarPubMed
Chapuy, MC, Preziosi, P, Maamer, M, Arnaud, S, Galan, P, Hercberg, S & Meunier, PJ (1997) Prevalence of vitamin D insufficiency in an adult normal population. Osteoporosis International 7, 439443.CrossRefGoogle Scholar
Chapuy, MC, Schott, AM, Garnero, P, Hans, D, Delmas, PD & Meunier, PJ (1996) Healthy elderly French women living at home have secondary hyperparathyroidism and high bone turnover in winter. EPIDOS Study Group. Journal of Clinical Endocrinology and Metabolism 81, 11291133.Google ScholarPubMed
Corless, D, Beer, M, Boucher, BJ & Gupta, SP (1975) Vitamin-D status in long-stay geriatric patients. Lancet i, 14041406.CrossRefGoogle Scholar
Danish Food Agency (1996) Danskernes Kostvaner 1995 (The Danish Dietary Survey 1995). Danish Food Agency Publication no. 235. Copenhagen, Denmark: Danish Food Agency.Google Scholar
Davies, PSW, Bates, CJ, Cole, TJ, Prentice, A & Clarke, PC (1999) Vitamin D seasonal and regional differences in preschool children in Great Britain. European Journal of Clinical Nutrition 53, 195198.CrossRefGoogle ScholarPubMed
Dawson-Hughes, B, Harris, SS & Dallal, GE (1997) Plasma calcidiol, season, and serum parathyroid hormone concentrations in healthy elderly men and women. American Journal of Clinical Nutrition 65, 6771.CrossRefGoogle ScholarPubMed
Deharveng, G, Charrondiere, UR, Slimani, N, Southgate, DAT & Riboli, E (1999) Comparison of nutrients in the food composition tables available in nine European countries participating in EPIC. European Journal of Clinical Nutrition 42, 24492453.Google Scholar
de Jong, N, Adam, SGM, de Groot, LCPGM, de Graaf, C & Executive Group for Development of Nutrient Dense Foods for Frail Elderly (2000) Variability of micronutrient content in enriched dairy and fruit products. International Journal of Food Science and Technology 51, 247257.Google ScholarPubMed
Deutsche Gesellschaft für Ernährung (2000) Ernährungsbericht 2000 (Nutrition Report 2000). Frankfurt am Mein: Druckerei Heinrich.Google Scholar
Docio, S, Riancho, JA, Perez, A, Olmos, JM, Amado, JA & Gonzalez-Macias, J (1998) Seasonal deficiency of vitamin D in children: a potential target for osteoporosis-preventing strategies? Journal of Bone and Mineral Research 13, 544548.CrossRefGoogle ScholarPubMed
Dunnigan, MG, Fraser, SA, Mclntosh, WB, Moseley, H & Sumner, DJ (1986) The prevention of vitamin D deficiency in the elderly. Scottish Medical Journal 31, 144149.Google ScholarPubMed
Egsmose, C, Lund, B, McNair, P, Lund, B, Storm, T & Sørensen, OH (1987) Low serum levels of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D in institutionalized old people: influence of solar exposure and vitamin D supplementation. Age and Ageing 16, 3540.CrossRefGoogle ScholarPubMed
Fardellone, P, Sebert, JL, Garabedian, M, Bellony, R, Maamer, M, Agbomson, F & Brazier, M (1995) Prevalence and biological consequences of vitamin D deficiency in elderly institutionalized subjects. Revue du Rhumatism 62, 576581.Google ScholarPubMed
Finch, S, Doyle, W, Lowe, C, Bates, CJ, Prentice, A, Smithers, G & Clarke, PC (1998) National Diet and Nutrition Survey: People Aged 65 Years and Over. vol. 1 , Report of the Diet and Nutrition Survey. London: H.M. Stationery Office.Google Scholar
Glerup, H (2000) Vitamin D mangel blandt immigranter (Vitamin D deficiency among immigrants). Ugeskrift for Laeger 162, 61966199.Google Scholar
Gloth, FM, Gundberg, CM, Hollis, BW, Haddad, JG & Tobin, JD (1995) Vitamin D deficiency in homebound elderly persons. Journal of the American Medical Association 274, 16831686.CrossRefGoogle ScholarPubMed
Guillemant, J, Cabrol, S, Allemandou, A, Peres, G & Guillemant, S (1995) Vitamin D-dependent seasonal variation in growing male adolescents. Bone 17, 513516.CrossRefGoogle ScholarPubMed
Guillemant, J, Taupin, P, Le, HT, Taright, N, Allemandou, A, Peres, G & Guillemant, S (1999) Vitamin D status during puberty in French healthy male adolescents. Osteoporosis International 10, 222225.CrossRefGoogle ScholarPubMed
Heaney, RP, Abrams, S, Dawson-Hughes, B, Looker, A, Marcus, R, Matkovic, V & Weaver, C (2000) Peak bone mass. Osteoporosis International 11, 9851009.CrossRefGoogle ScholarPubMed
Heaney, RP, Davies, KM, Chen, TC, Holick, MF & Barger-Lux, MJ (2003) Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol. American Journal of Clinical Nutrition 77, 204210.CrossRefGoogle ScholarPubMed
Hegarty, V, Woodhouse, P & Khaw, KT (1994) Seasonal variation in 25-hydroxyvitamin D and parathyroid hormone concentrations in healthy elderly people. Age and Ageing 23, 478482.CrossRefGoogle ScholarPubMed
Holick, MF (1995) Environmental factors that influence the cutaneous production of vitamin D. American Journal of Clinical Nutrition 61, Suppl. 638S645S.CrossRefGoogle ScholarPubMed
Holick, MF (1996) Environmental factors that influence the cutaneous production of vitamin D. Journal of Nutrition 126, 1159S1164S.CrossRefGoogle Scholar
Holick, MF (1998) Redefining vitamin D insufficiency. Lancet 351, 805806.Google Scholar
Holick, MF, MacLaughlin, JA, Clark, MB, Holick, SA, Pots, JT, Anderson, RR, Blank, IH, Aarrish, JA & Elias, P (1980) Photo-synthesis of previtamin D 3 in human skin and the physiologic consequences. Science 210, 203205.CrossRefGoogle Scholar
Hollis, BW (1996) Assessment of vitamin D nutritional and hormonal status: what to measure and how to do it. Calcified Tissue International 58, 45.CrossRefGoogle ScholarPubMed
Hollis, BW (2000) Comparison of commercially available 125 I-based RIA methods for the determination of circulating 25-hydroxyvitamin D. Clinical Chemistry 46, 16571661.CrossRefGoogle ScholarPubMed
Hulshof, KFAM, Kistemaker, C & Bouman, M (1998) De inname van energie en voedingsstoffen door Nederlandse bevolkings-groepen – Voedselconsumptiepeiling 1997–1998 (The Intake of Energy and Nutrients in the Dutch Population – Food Consumption Survey 1997–1998). TNO Report V98–805 Zeist, The Netherlands: TNO.Google Scholar
Hutchison, FN & Bell, NH (1992) Osteomalacia and rickets. Seminars in Nephrology 12, 127145.Google ScholarPubMed
Iqbal, SJ, Kaddam, I, Wassif, W, Nichol, F & Walls, J (1994) Continuing clinically severe vitamin D deficiency in Asians in the UK (Leicester). Postgraduate Medical Journal 70, 708714.CrossRefGoogle ScholarPubMed
Jesudason, D, Need, AG, Horowitz, M, O'Loughlin, PD, Morris, HA & Nordin, BE (2002) Relationship between serum 25-hydroxyvitamin D and bone resorption markers in vitamin D insufficiency. Bone 31, 626630.CrossRefGoogle ScholarPubMed
Johansson, L & Solvoll, K (1999) Norkost 1997, Statens Råd for Ernoring og Fysisk Aktivitet. Rapport no. 2/1999. Oslo, Norway: Statens Ernæringsrad.Google Scholar
Juttmann, JR, Visser, TJ, Buurman, C, de Kam, E & Birkenhager, JC (1981) Seasonal fluctuations in serum concentrations of vitamin D metabolites in normal subjects. British Medical Journal 282, 13491352.CrossRefGoogle ScholarPubMed
Kauppinen-Mäkelin, R, Tähtelä, R, Löoyttyniemi, E, Kärkkäinen, J & Välimäki, MJ (2001) A high prevalence of hypovitaminosis D in Finnish medical in- and outpatients. Journal of Internal Medicine 249, 559563.CrossRefGoogle ScholarPubMed
Keane, EM, Healy, M, O'Moore, RO & Walsh, JB (1998) Vitamin D-fortified liquid milk: benefits for the elderly community-based population. Calcified Tissue International 62, 300302.CrossRefGoogle ScholarPubMed
Keane, EM, Rochfort, A, Cox, J, McGovern, D, Coakley, D & Walsh, JB (1992) Vitamin-D-fortified liquid milk – a highly effective method of vitamin D administration for house-bound and institutionalised elderly. Gerontology 38, 280284.CrossRefGoogle ScholarPubMed
Kimlin, MG, Downs, NJ & Parisi, AV (2003) Comparison of human facial UV exposure at high and low latitudes and the potential impact on dermal vitamin D production. Photochemical and Photobiological Sciences 2, 370375.CrossRefGoogle ScholarPubMed
Knudsen, VK, Rasmussen, LB, Haraldsdottir, J, Ovesen, L, Bulow, I, Knudsen, N, Jorgensen, T, Laurberg, P & Perrild, H (2002) Use of dietary supplements in Denmark is associated with health and former smoking. Public Health Nutrition 5, 463468.CrossRefGoogle Scholar
Krall, EA, Sahyoun, N, Tannenbaum, S, Dallal, GE & Dawson-Hughes, B (1989) Effect of vitamin D intake on seasonal variations in parathyroid hormone secretion in postmenopausal women. New England Journal of Medicine 321, 17771783.CrossRefGoogle ScholarPubMed
Kristinsson, , Valdimarsson, O, Sigurdsson, G, Franzson, L, Olafsson, I & Steingrimsdottir, L (1998) Serum 25-hydroxy-vitamin D levels and bone mineral density in 16–20 years-old girls: lack of association. Journal of Internal Medicine 243, 381388.CrossRefGoogle Scholar
Kudlacek, S, Schneider, B, Peterlik, M, Leb, G, Klaushofer, K, Weber, K, Woloszczuk, W & Willvonseder, R (2003) Assessment of vitamin D and calcium status in healthy adult Austrians. European Journal of Clinical Investigation 33, 323331.CrossRefGoogle ScholarPubMed
Lamberg-Allardt, CJ, Outila, TA, Karkkainen, MU, Rita, HJ & Valsta, LM (2001) Vitamin D deficiency and bone health in healthy adults in Finland: could this be a concern in other parts of Europe? Journal of Bone and Mineral Research 16, 20662073.CrossRefGoogle ScholarPubMed
Lehtonen-Veromaa, M, Mottonen, T, Irjala, K, Karkkainen, M, Lamberg-Allardt, C, Hakola, P & Viikari, J (1999) Vitamin D intake is low and hypovitaminosis D common in healthy 9- to 15-year-old Finnish girls. European Journal of Clinical Nutrition 53, 746751.CrossRefGoogle ScholarPubMed
Lehtonen-Veromaa, MK, Mottonen, TT, Nuotio, IO, Irjala, KM, Leino, AE & Viikari, JS (2002) Vitamin D and attainment of peak bone mass among peripubertal Finnish girls: a 3-y prospective study. American Journal of Clinical Nutrition 76, 14461453.CrossRefGoogle ScholarPubMed
Lips, P (2001) Vitamin D deficiency and secondary hyperparathyroidism in the elderly: consequences for bone loss and fractures and therapeutic implications. Endocrine Reviews 22, 477501.CrossRefGoogle ScholarPubMed
Lips, P, Bouillon, R, Jongen, MJ, Van Ginkel, FC, van der Vijgh, WJ & Netelenbos, JC (1985) The effect of trauma on serum concentrations of vitamin D metabolites in patients with hip fracture. Bone 6, 6367.CrossRefGoogle ScholarPubMed
Lips, P, Chapuy, MC, Dawson-Hughes, B, Pols, HAP & Holick, MF (1999) An international comparison of serum 25-hydroxy-vitamin D measurements. Osteoporosis International 9, 394397.CrossRefGoogle Scholar
Lips, P, Van Ginkel, FC, Jongen, MJ, Rubertus, F, van der Vijgh, WJ & Netelenbos, JC (1987) Determinants of vitamin D status in patients with hip fracture and in elderly control subjects. American Journal of Clinical Nutrition 46, 10051010.CrossRefGoogle ScholarPubMed
McKenna, MJ (1992) Differences in vitamin D status between countries in young adults and the elderly. American Journal of Medicine 93, 6977.CrossRefGoogle ScholarPubMed
McKenna, MJ & Freaney, R (1998) Secondary hyperparathyroidism in the elderly: means to defining hypovitaminosis D. Osteporosis International 8, Suppl S3S6.CrossRefGoogle ScholarPubMed
McKenna, MJ, Freaney, R, Meade, A & Muldowney, FP (1985) Hypovitaminosis D and elevated serum alkaline phosphatase in elderly Irish people. American Journal of Clinical Nutrition 41, 101109.CrossRefGoogle ScholarPubMed
MacLaughlin, J & Holick, MF (1985) Aging decreases the capacity of human skin to produce vitamin D 3. Journal of Clinical Investigation 76, 15361538.CrossRefGoogle Scholar
Malabanan, A, Veronikis, IE & Holick, MF (1988) Redefining vitamin D insufficiency. Lancet 351, 805806.CrossRefGoogle Scholar
Melin, AL, Wilske, J, Ringertz, H & Saaf, M (1999) Vitamin D status, parathyroid function and femoral bone density in an elderly Swedish population living at home. Aging 11, 200207.Google Scholar
Meller, Y, Kestenbaum, RS, Shany, S, Galinsky, D, Zuili, I, Yankovitch, N, Giat, J, Conforti, A & Torok, G (1985) Parathormone, calcitonin, and vitamin D metabolites during normal fracture healing in geriatric patients. Clinical Orthopaedics 199, 272279.CrossRefGoogle Scholar
Meulmeester, JF, van den Berg, H, Wedel, M, Boshuis, PG, Hulshof, KF & Luyken, R (1990) Vitamin D status, parathyroid hormone and sunlight in Turkish, Moroccan and Caucasian children in The Netherlands. European Journal of Clinical Nutrition 44, 461470.Google ScholarPubMed
Morris, HA, Morrison, GW, Burr, M, Thomas, DW & Nordin, BE (1984) Vitamin D and femoral neck fractures in elderly South Australian women. Medical Journal of Australia 140, 519521.CrossRefGoogle ScholarPubMed
Mowé, MM, Bøhmer, T & Haug, E (1996) Serum calcidiol and calcitriol concentrations in elderly people: variations with age, sex, season and disease. Clinical Nutrition 15, 201206.CrossRefGoogle ScholarPubMed
Nayal, AS, MacLennan, WJ, Hamilton, JC, Rose, P & Kong, M (1978) 25-Hydroxyvitamin D, diet and sunlight exposure in patients admitted to a geriatric unit. Gerontology 24, 117122.CrossRefGoogle Scholar
Nordic Council of Ministers (1995) Addition of Nutrients to Food – Principles and Practices. TemaNord, p. 643 Oslo, Norway: The Nordic Council of Ministers.Google Scholar
Ooms, ME, Lips, P, Roos, JC, van der Vijgh, WJF, Popp-Snijders, C, Bezemer, PD & Bouter, LM (1995a) Vitamin D status and sex hormone binding globulin: determinants of bone turnover and bone mineral density in elderly women. Journal of Bone and Mineral Research 10, 11771184.CrossRefGoogle ScholarPubMed
Ooms, ME, Roos, JC, Bezemer, PD, van der Vijgh, WJF, Bouter, LM & Lips, P (1995b) Prevention of bone loss by vitamin D supplementation in elderly women: a randomised double blind trial. Journal of Clinical Endocrinology and Metabolism 80, 10521058.Google Scholar
Outila, TA, Karkkainen, MU, Lamberg-Allardt, CJ (2001) Vitamin D status affects serum parathyroid hormone concentrations during winter in female adolescents: associations with forearm bone mineral density. American Journal of Clinical Nutrition 74, 206210.CrossRefGoogle ScholarPubMed
Ovesen, L, Brot, C & Jakobsen, J (2003) Food contents and biological activity of 25-hydroxyvitamin D: a vitamin D metabolite to be reckoned with?. Annals of Nutrition and Metabolism 47, 107113.CrossRefGoogle Scholar
Parfitt, AM (1998). Osteomalacia and related disorders. In Metabolic Bone Disease and Clinically Related Disorders,pp.327386 [Avioli, LV, and Krane, SM,editors]. San Diego, CA: Academic Press.CrossRefGoogle Scholar
Parfitt, AM, Gallagher, JC, Heaney, RP, Johnston, CC, Neer, R & Whedon, GD (1982) Vitamin D and bone health in the elderly. American Journal of Clinical Nutrition 36, 10141031.CrossRefGoogle ScholarPubMed
Prentice, A (2002) What are dietary requirements for calcium and vitamin D?. Calcified Tissue International 70, 8388.CrossRefGoogle ScholarPubMed
Quesada, JM, Jans, I, Benito, P, Jimenez, A & Boillon, R (1989) Vitamin D status of elderly people in Spain. Age and Ageing 18, 392397.CrossRefGoogle ScholarPubMed
Reginster, JY, Frederick, I, Deroisy, R, Dewe, W, Taquet, AN, Albert, A, Collette, J, Pirenne, H, Zheng, SX & Gosset, C (1998) Parathyroid hormone plasma concentrations in response to low 25-OH vitamin D circulating levels increases with age in elderly women. Osteoporosis International 8, 390392.Google ScholarPubMed
Sahota, O, Masud, T, San, P & Hosking, DJ (1999) Vitamin D insufficiency increases bone turnover markers and enhances bone loss at the hip in patients with established vertebral osteoporosis. Clinical Endocrinology 51, 217221.CrossRefGoogle ScholarPubMed
Scharla, SH, Scheidt-Nave, C, Leidig, G, Woitge, H, Wuster, C, Seibel, MJ & Ziegler, R (1996) Lower serum 25-hydroxyvitamin D is associated with increased bone resorption markers and lower bone density at the proximal femur in normal females: a population-based study. Experimental and Clinical Endocrinology and Diabetes 104, 289292.CrossRefGoogle ScholarPubMed
Scragg, R, Khaw, K-T & Murphy, S (1995) Life-style factors associated with winter serum 25-hydroxyvitamin D levels in elderly adults. Age and Ageing 24, 271275.CrossRefGoogle ScholarPubMed
Sem, SW, Sjoen, RJ, Trygg, K & Pedersen, JI (1987) Vitamin D status of two groups of elderly in Oslo: living in old people's homes and living in own homes. Comprehensive Gerontology 1A, 126130.Google Scholar
Shepard, RM & DeLuca, HF (1980) Plasma concentrations of vitamin D 3 and its metabolites in the rat as influenced by vitamin D 3 or 25-hydroxyvitamin D 3 intakes. Archives of Biochemistry and Biophysiscs 202, 4353.CrossRefGoogle Scholar
Sigurdsson, G, Franzson, L, Steingrimsdottir, L & Sigvaldason, H (2000) The association between parathyroid hormone, vitamin D and bone mineral density in 70-year-old Icelandic women. Osteoporosis International 11, 10311035.CrossRefGoogle ScholarPubMed
Solanki, T, Hyatt, RH, Kemm, JR, Hughes, EA & Cowan, RA (1995) Are elderly Asians in Britain at a high risk of vitamin D deficiency and osteomalacia?. Age and Ageing 24, 103107.CrossRefGoogle Scholar
Souberbielle, JC, Cormier, C, Kindermans, C, Gao, P, Cantor, T, Forette, F & Baulieu, EE (2001) Vitamin D status and redefining serum parathyroid hormone reference range in the elderly. Journal of Clinical Endocrinology and Metabolism 86, 30863090.Google ScholarPubMed
Thomas, MK, Lloyd-Jones, DM, Thadhani, RI, Shaw, AC, Deraska, DJ, Kitch, BT, Vamvakas, EC, Dick, IM, Prince, RL & Finkelstein, JS (1998) Hypovitaminosis D in medical inpatients. New England Journal of Medicine 338, 777783.CrossRefGoogle ScholarPubMed
Tjellesen, L & Christiansen, C (1983) Vitamin D metabolites in normal subjects during one year. A longitudinal study. Scandinavian Journal of Clinical Laboratory and Investigation 43, 8589.CrossRefGoogle ScholarPubMed
Toss, G, Almqvist, S, Larsson, L & Zetterqvist, H (1980) Vitamin D deficiency in welfare institutions for the aged. Acta Medica Scandinavica 208, 8789.CrossRefGoogle ScholarPubMed
van der Wielen, RPJ, Löwik, MRH, van den Berg, H, de Groot, LCPGM, Haller, J, Moreiras, O & Van Staveren, WA (1995) Serum vitamin D concentrations among elderly people in Europe. Lancet 346, 207210.CrossRefGoogle ScholarPubMed
Vieth, R, Chan, P-CR & MacFarlane, GD (2001) Efficacy and safety of vitamin D 3 intake exceeding the lowest observed adverse effect level. American Journal of Clinical Nutrition 73, 288294.CrossRefGoogle ScholarPubMed
Vir, SC & Love, AHG (1978) Vitamin D status of elderly at home and institutionalised in hospital. International Journal of Vitamin and Nutrition Research 48, 123130.Google ScholarPubMed
Volatier, J-L (2000) Enquête Individuelle et Nationale sur les consommations Alimentaires (Individual and National Study of Food Consumption). Paris: Editions TEC et DOC Lavoisier.Google Scholar
von Knorring, J, Slatis, P, Weber, TH & Helenius, T (1982) Serum levels of 25-hydroxyvitamin D, 24,25-dihydroxyvitamin D and parathyroid hormone in patients with femoral neck fracture in southern Finland. Clinical Endocrinology 17, 189194.CrossRefGoogle ScholarPubMed
Webb, AR, Kline, L & Holick, MF (1988) Influence of season and latitude on the cutaneous synthesis of vitamin D 3 exposure to winter sunlight in Boston and Edmonton will not promote vitamin D 3 synthesis in human skin. Journal of Clinical Endocrinology and Metabolism 67, 373378.CrossRefGoogle Scholar
Woitge, HW, Scheidt-Nave, C, Kissling, C, Leidig-Bruckner, G, Meyer, K, Grauer, A, Scharla, SH, Ziegler, R & Seibel, MJ (1998) Seasonal variation of biochemical indexes of bone turnover: results of a population-based study. Clinical Endocrinology and Metabolism 83, 6875.Google ScholarPubMed