Commonly recommended daily intake of vitamin D is not sufficient if sunlight exposure is limited

Abstract

Abstract. Glerup H, Mikkelsen K, Poulsen L, Hass E, Overbeck S, Thomsen J, Charles P, Eriksen EF (University Hospital of Aarhus, and Primary Health Care Centre, City Vest, Aarhus, Denmark). Commonly recommended daily intake of vitamin D is not sufficient if sunlight exposure is limited. J Intern Med 2000; 247: 260±268.Objectives. Sunlight exposure of the skin is known to be the most important source of vitamin D. The aims of this study were: (i) to estimate vitamin D status amongst sunlight-deprived individuals (veiled Arab women, veiled ethnic Danish Moslem women and Danish controls); and (ii) through food intake analysis to estimate the oral intake of vitamin D necessary to keep a normal vitamin D status in sunlight-deprived individuals. Design. Cross-sectional study amongst randomly selected Moslem women of Arab origin living in Denmark. Age-matched Danish women were included as controls. To control for racial differences, a group of veiled ethnic Danish Moslem women (all Caucasians) was included. Setting. Primary

Effect of vitamin D supplementation on vitamin D status and bone turnover markers in young adults

“…Research to date has indicated that the usual dietary vitamin D intake in Europe is not sufficient to maintain adequate vitamin D status during wintertime when synthesis is minimal (Holick, 1994;Glerup et al, 2000;Ovesen et al, 2003;Hill et al, 2004). The results of the current study support this hypothesis.…”

“…In countries around the equator, UV light and, therefore, the production of vitamin D, is constant throughout the year (Glerup et al, 2000). However, seasonal variation in UV intensity, as occurs both far North and South of the equator, results in marked variation in vitamin D status throughout the year, with highest concentrations found in late summer and markedly lower concentrations observed in late winter (McLaughlin et al, 1974;McKenna, 1992).…”

Vitamin D insufficiency in older female community-dwelling acute hospital admissions and the response to supplementation

“…They calculated that a dose of 400 IU/day would elevate serum 25(OH)D 3 by only 7.0 nmol/l. Several groups have reached the same conclusion, namely that, without appreciable cutaneous synthesis, current cholecalciferol input recommendations are inadequate (Glerup et al, 2000;Vieth et al, 2001). There have been no studies showing toxic effects of higher doses of vitamin D, and Vieth et al (2001) proposed that the evidence available today indicates that a value of 2000 IU/day for the tolerable upper input level is too low.…”

La vitamine D : effets « classiques », « non classiques » et évaluation du statut du patient

“…Les deux conséquences principales de cette nouvelle définition du seuil d'insuffisance en vitamine D sont : l'insuffisance en vitamine D est très fréquente : à des latitudes >408 (l'Europe par exemple) et suivant les populations testées et la période de l'année, 50 à presque 100% des individus ne recevant pas de supplémentation ont une concentration sérique de 25OHD inférieure à 30 ng/mL [77][78][79][80][81][82][83][84] (et Tableau 1) ; les apports nutritionnels conseillés (ANC) pour la vitamine D (400 U/J pour les sujets de moins de 65 ans et 600 U/J pour ceux de plus de 65 ans) sont insuffisants pour atteindre cette cible minimale de 30 ng/mL de 25OHD [85] et il faut donc envisager des doses plus importantes. Il est légitime alors de se poser la question d'un éventuel surdosage.…”