The study

Hypponen E, Power C.
Hypovitaminosis D in British adults at age 45 y: nationwide cohort
study of dietary and lifestyle predictors.
Am J Clin Nutr. 2007 Mar;85(3):860-8.
PMID: 17344510 [PubMed - in process]
<http://www.ajcn.org/cgi/content/abstract/85/3/860>

published in the latest issue of AJCN investigated vitamin D status
(serum calcidiol a.k.a (25(OH)D concentrations) of British adults at
age 45 and found that the prevalence of hypovitaminosis D
was alarmingly high during the winter and spring. Below the abstract
of the study:

   "BACKGROUND: Increased awareness of the importance of vitamin
   D to health has led to concerns about the prevalence of
   hypovitaminosis D in many parts of the world. OBJECTIVES: We
   aimed to determine the prevalence of hypovitaminosis D in the
   white British population and to evaluate the influence of key
   dietary and lifestyle risk factors. DESIGN: We measured 25-
   hydroxyvitamin D [25(OH)D] in 7437 whites from the 1958
   British birth cohort when they were 45 y old. RESULTS: The
   prevalence of hypovitaminosis D was highest during the winter
   and spring, when 25(OH)D concentrations <25, <40, and <75
   nmol/L were found in 15.5%, 46.6%, and 87.1% of participants,
   respectively; the proportions were 3.2%, 15.4%, and 60.9%,
   respectively, during the summer and fall. Men had higher
   25(OH)D concentrations, on average, than did women during the
   summer and fall but not during the winter and spring (P =
   0.006, likelihood ratio test for interaction). 25(OH)D
   concentrations were significantly higher in participants who
   used vitamin D supplements or oily fish than in those who did
   not (P < 0.0001 for both) but were not significantly higher
   in participants who consumed vitamin D-fortified margarine
   than in those who did not (P = 0.10). 25(OH)D concentrations
   <40 nmol/L were twice as likely in the obese as in the
   nonobese and in Scottish participants as in those from other
   parts of Great Britain (ie, England and Wales) (P < 0.0001
   for both). CONCLUSION: Prevalence of hypovitaminosis D in the
   general population was alarmingly high during the winter and
   spring, which warrants action at a population level rather
   than at a risk group level."

In the same issue of AJCN there is a Dutch vitamin D study

van Dam RM, Snijder MB, Dekker JM, Stehouwer CD, Bouter LM, Heine RJ,
Lips P.
Potentially modifiable determinants of vitamin D status in an older
population in the Netherlands: the Hoorn Study.
Am J Clin Nutr. 2007 Mar;85(3):755-761.
PMID: 17344497 [PubMed - as supplied by publisher]
<http://www.ajcn.org/cgi/content/abstract/85/3/755>,

which found that low vitamin D status among elderly people is very
common also in Holland. Here's its abstract:

   "BACKGROUND: Inadequate vitamin D status is common in many
   populations around the world. OBJECTIVE: The aim was to
   evaluate potentially modifiable determinants of vitamin D
   status in an older population. DESIGN: This was a cross-
   sectional study from a population-based cohort including 538
   white Dutch men and women aged 60-87 y. Vitamin D status was
   assessed by plasma 25-hydroxyvitamin D [25(OH)D]
   concentrations. RESULTS: In the winter period, 51% of the
   subjects had 25(OH)D concentrations <50.0 nmol/L. Greater
   body fatness and less time spent on outdoor physical activity
   were associated with worse vitamin D status. Regular use of
   vitamin D-fortified margarine products [odds ratio (OR) in a
   comparison of intake of >/=20 g/d with none: 0.41; 95% CI:
   0.20, 0.86; P for trend < 0.001], fatty fish (OR for servings
   of >/=2/mo versus none: 0.41; 95% CI: 0.16, 1.04; P for trend
   = 0.01), and vitamin D-containing supplements (OR for >/= 1/d
   versus none: 0.33; 95% CI: 0.17, 0.63; P for trend < 0.001)
   were inversely associated with vitamin D inadequacy [25(OH)D
   <50.0 nmol/L]. We estimated that combined use of margarine
   products (20 g/d), fatty fish (100 g/wk), and vitamin D
   supplements (>/=1/d) was associated with a 16.8 nmol/L higher
   25(OH)D concentration than was the use of none of these.
   However, none of the participants reached these intakes for
   all 3 factors. CONCLUSION: Because few foods are vitamin D-
   fortified and the amounts of vitamin D in supplements are
   low, it is difficult to achieve adequate vitamin D status
   through increasing intakes in the Netherlands and in
   countries with similar policies."

The editorial of the same issue,

Vieth R, Bischoff-Ferrari H, Boucher BJ, Dawson-Hughes B, Garland CF,
Heaney RP, Holick MF, Hollis BW, Lamberg-Allardt C, McGrath JJ, Norman
AW, Scragg R, Whiting SJ, Willett WC, Zittermann A.
The urgent need to recommend an intake of vitamin D that is effective.
Am J Clin Nutr. 2007 Mar;85(3):649-50.
PMID: 17344484 [PubMed - in process]
<http://www.ajcn.org/cgi/content/full/85/3/649>,

whose list of authors is packed with the most famous and appreciated
vitamin D researchers and also includes Harvard's Walter C. Willett,
comments the study by Hyppönen and Power, states the urgent need to
raise vitamin D recommendations, and appeals to the authorities and
other policy makers, media, vitamin manufacturers, etc., to work for
this goal to get that done as soon as possible. Below a couple of
excerpts from this article:

   "The report by Hyppönen and Power in this issue of the
   Journal (1) highlights a frustrating and regrettable
   situation for nutrition researchers. In the early 1970s, the
   same serum 25-hydroxyvitamin D [25(OH)D] concentrations
   reported by Hyppönen and Power were thought to be indicative
   of "healthy" white adults in the United Kingdom (2). However,
   during those early years after the discovery of 25(OH)D, the
   adequacy of its serum concentration was based simply on
   whether the concentration was enough to prevent osteomalacia
   or rickets. Three decades later, we know that 25(OH)D
   concentrations relate to many other aspects of health,
   including fracture risk, bone density, colon cancer, and even
   tooth attachment (3); we also know that much higher
   concentrations of 25(OH)D are needed to prevent adverse
   outcomes. Indeed, in the 1958 British birth cohort, lower
   25(OH)D is associated with a higher percentage of hemoglobin
   A1C (a measure of long-term glucose concentration), which
   further emphasizes the need to maintain optimal 25(OH)D
   concentrations (4).

   [...]

   It is important for major journals such as the AJCN to
   publish evidence of a widespread nutrient deficiency.
   Regrettably, we are now stuck in a revolving cycle of
   publications that are documenting the same vitamin D
   inadequacy (1-3, 5, 7-9, 13-17). This phenomenon has been
   referred to as "circular epidemiology" (18), and, for vitamin
   D, the phenomenon will continue for as long as the levels of
   vitamin D fortification and supplementation and the practical
   advice offered to the public remain essentially the same as
   they were in the era before we knew that 25(OH)D even
   existed. As scientists, the purpose of our work is to improve
   the health of the public. We know the realities of serum
   25(OH)D concentrations in populations around the world, and
   we have come to the conclusion that public health will
   benefit from improved vitamin D nutritional status. We know
   the intakes of vitamin D needed to bring about desirable
   25(OH)D concentrations, so why is the science not making a
   difference to public health? A major reason is that there is
   little public pressure on policy makers to support efforts to
   update recommendations about nutrition. Public pressure is
   generally rooted in the media, but we do not think that the
   public media present the vitamin D story in a complete and
   accurate manner. Reports about vitamin D inadequacies are
   presented straightforwardly, but, when it comes to discussing
   the intake of vitamin D needed to correct the situation,
   outdated official recommendations for vitamin D are
   propagated by the public media. This probably occurs because
   of restrictive editorial policies driven by concern about
   possible litigation if media were to advise a "toxic" intake
   greater than the UL. The unfortunate result is that there is
   minimal motivation for policy makers to implement the
   relatively simple steps that could correct this nutrient
   deficiency.
   
   Because of the convincing evidence for benefit and the strong
   evidence of safety, we urge those who have the ability to
   support public health - the media, vitamin manufacturers, and
   policy makers - to undertake new initiatives that will have a
   realistic chance of making a difference in terms of vitamin D
   nutrition. We call for international agencies such as the
   Food and Nutrition Board and the European Commission's Health
   and Consumer Protection Directorate-General to reassess as a
   matter of high priority their dietary recommendations for
   vitamin D, because the formal nationwide advice from health
   agencies needs to be changed."