Serum vitamin D concentrations among elderly people in Europe.
Vitamin D status decreases with age, mainly as a result of restricted sunlight exposure, reduced capacity of the skin to produce vitamin D, and reduced dietary vitamin D intake. We measured wintertime serum 25-hydroxyvitamin D [25(OH)D] concentrations in 824 elderly people from 11 European countries. 36% of men and 47% of women had 25(OH)D concentrations below 30 nmol/L. Users of vitamin D supplements and/or sunlamps had higher 25(OH)D (median 54 nmol/L) than non users (median 31 nmol/L). Surprisingly, lowest mean 25(OH)D concentrations were seen in southern European countries. Low 25(OH)D concentrations could largely be explained by attitudes towards sunlight exposure and factors of physical health status, after exclusion of users of vitamin D supplements or sunlamps. Problems with daily living activities and wearing clothes with long sleeves during periods of sunshine were strong predictors of low wintertime serum 25(OH)D concentrations. These findings show that free-living elderly Europeans, regardless of geographical location, are at substantial risk of inadequate vitamin D status during winter and that dietary enrichment or supplementation with vitamin D should be seriously considered during this season.
van der Wielen
R P
RP
Department of Human Nutrition, Wageningen Agricultural University, The Netherlands.
Löwik
M R
MR
van den Berg
H
H
de Groot
L C
LC
Haller
J
J
Moreiras
O
O
van Staveren
W A
WA
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood*; D002112:Calcifediol / Q000097:blood; D015331:Cohort Studies; D004034:Diet Surveys; D004435:Eating / Q000502:physiology*; D005060:Europe; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D012621:Seasons; D013472:Sunlight; D011795:Surveys and Questionnaires; D014807:Vitamin D / Q000008:administration & dosage / Q000097:blood*
D014807:Vitamin D; D002112:Calcifediol