Prevalence of hypovitaminosis D in UK and Holland alarmingly high in winter, urgent need to recommend EFFECTIVE doses [Prostate Cancer]

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From: Matti Narkia on 12 Mar 2007 04:07

On Sun, 11 Mar 2007 13:26:32 +0200, Matti Narkia <mna(a)mbnet.fi> wrote:

>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.

[snip]

>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 Hypp�nen 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.

A related news article:

Vitamin D level reassessment high priority, say experts
<http://www.nutraingredients-usa.com/news/ng.asp?n=74831-vitamin-d-supplements-tolerable-upper-intake-level>

"3/9/2007 - International agencies should reassess as a
matter of high priority dietary recommendations for vitamin
D, experts have said, because current advice is outdated and
puts the public at risk of deficiency.

Fifteen experts from universities, research institutes, and
university hospitals around the world, led by Reinhold Vieth
from Toronto's Mount Sinai Hospital wrote in the American
Journal of Clinical 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."

"The balance of the evidence leads to the conclusion that the
public health is best served by a recommendation of higher
daily intakes of vitamin D. Relatively simple and low-cost
changes, such as increased food fortification or increasing
the amount of vitamin D in vitamin supplement products, may
very well bring about rapid and important reductions in the
morbidity associated with low vitamin D status," they said.

The editorial was written in response to a UK-based study,
published in the same journal, which reported that there
exists an alarmingly high prevalence of hypovitaminosis D in
the general population during the winter and spring.

Vitamin D refers to two biologically inactive precursors -
D3, also known as cholecalciferol, and D2, also known as
ergocalciferol. The former, produced in the skin on exposure
to UVB radiation (290 to 320 nm), is said to be more
bioactive. The latter is derived from plants and only enters
the body via the diet.

Both D3 and D2 precursors are hydroxylated in the liver and
kidneys to form 25- hydroxyvitamin D (25(OH)D), the non-
active 'storage' form, and 1,25-dihydroxyvitamin D (1,25(OH)
2D), the biologically active form that is tightly controlled
by the body.

The study, by Elina Hypp�nen and Chris Power from the
Institute of Child Health in London, measured the level of
25(OH)D in 7437 whites from the 1958 British birth cohort
when the subjects had reached the age of 45.

Hypp�nen and Power report that prevalence of low vitamin D
levels was highest during the winter and spring, when 46.6
per cent of participants had 25(OH)D concentrations of less
than 40 nanomoles per litre while this fell to 15.4 per cent
during the summer and autumn.

Vitamin D is produced in the skin on exposure to UVB
radiation and can also be consumed in small amounts from the
diet. However, recent studies have shown that sunshine levels
in some northern countries are so weak during the winter
months that the body makes no vitamin D at all, leading some
to estimate that over half of the population in such
countries have insufficient or deficient levels of the
vitamin.

"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," concluded the researchers.

Vieth and his collaborators said the study was yet another
publication in a series that document low vitamin D levels,
and this will continue while recommended levels of vitamin D
intake remain outdated.

"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," wrote Vieth and collaborators.

A recent review of the science reported that the tolerable
upper intake level for oral vitamin D3 should be increased
five-fold, from the current tolerable upper intake level (UL)
in Europe and the US of 2000 International Units (IU),
equivalent to 50 micrograms per day, to 10,000 IU (250
micrograms per day).

Source: The American Journal of Clinical Nutrition
March 2007, Volume 85, Number 3, Pages 860-868
"Hypovitaminosis D in British adults at age 45 y: nationwide
cohort study of dietary and lifestyle predictors"
Authors: E. Hypp�nen and C. Power

Editorial: The American Journal of Clinical Nutrition
March 2007, Volume 85, Number 3, Pages 649-650
"The urgent need to recommend an intake of vitamin D that is
effective"
Authors: R. Vieth, H. Bischoff-Ferrari, B.J. Boucher, B.
Dawson- Hughes, C.F. Garland, R.P. Heaney, M.F. Holick, B.W.
Hollis, C. Lamberg-Allardt, J.J. McGrath, A.W. Norman, R.
Scragg, S.J. Whiting, W.C. Willett, and A. Zittermann"

--
Matti Narkia

From: Matti Narkia on 13 Mar 2007 07:33

On Mon, 12 Mar 2007 14:53:00 -0500, Ed Friedman <ed(a)math.uchicago.edu>
wrote:

>Matti Narkia wrote:
>> 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.
>
>Matti,
>
>What is the optimum serum level of D3 according to these researchers. I
>know that the labs around here say "normal" is between the range of 20-75.
>
The current consensus among top vitamin D reserchers seems to be that
the optimal serum calcidiol (25(OH)D) concentration is about 100
nmol/L. This requires in average perhaps 4000 IU of vitamin D3/d. In
the winter this is almost impossible to get in the regions outside the
40th latitudes, so one needs to take supplements in these areas in the
winter to guarantee optimal vitamin D status. I've been taking 4000
IU/d in the winter for years.

References:

Bischoff-Ferrari HA, Giovannucci E, Willett WC, Dietrich T,
Dawson-Hughes B.
Estimation of optimal serum concentrations of 25-hydroxyvitamin D for
multiple health outcomes.
Am J Clin Nutr. 2006 Jul;84(1):18-28. Review. Erratum in: Am J Clin
Nutr. 2006 Nov;84(5):1253. dosage error in abstract.
PMID: 16825677 [PubMed - indexed for MEDLINE]
<http://www.ajcn.org/cgi/content/full/84/1/18http://www.ajcn.org/cgi/content/full/84/1/18>

"Recent evidence suggests that vitamin D intakes above
current recommendations may be associated with better health
outcomes. However, optimal serum concentrations of 25-
hydroxyvitamin D [25(OH)D] have not been defined. This review
summarizes evidence from studies that evaluated thresholds
for serum 25(OH)D concentrations in relation to bone mineral
density (BMD), lower-extremity function, dental health, and
risk of falls, fractures, and colorectal cancer. For all
endpoints, the most advantageous serum concentrations of
25(OH)D begin at 75 nmol/L (30 ng/mL), and the best are
between 90 and 100 nmol/L (36-40 ng/mL). In most persons,
these concentrations could not be reached with the currently
recommended intakes of 200 and 600 IU vitamin D/d for younger
and older adults, respectively. A comparison of vitamin D
intakes with achieved serum concentrations of 25(OH)D for the
purpose of estimating optimal intakes led us to suggest that,
for bone health in younger adults and all studied outcomes in
older adults, an increase in the currently recommended intake
of vitamin D is warranted. An intake for all adults of > or =
1000 IU (25 microg) [corrected] vitamin D (cholecalciferol)/d
is needed to bring vitamin D concentrations in no less than
50% of the population up to 75 nmol/L. The implications of
higher doses for the entire adult population should be
addressed in future studies."

Vieth R.
What is the optimal vitamin D status for health?
Prog Biophys Mol Biol. 2006 Sep;92(1):26-32. Review.
PMID: 16766239 [PubMed - indexed for MEDLINE]
<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=16766239>

"The most objectively substantiated health-related reason for
tanning is that it improves vitamin D status. The serum 25-
hydroxyvitamin D concentration (25(OH)D) is the measure of
vitamin D nutrition status. Human biology was probably
optimized through natural selection for a sun-rich
environment that maintained serum 25(OH)D higher than 100
nmol/L. These levels are now only prevalent in people who
spend an above-average amount of time outdoors, with the sun
high in the sky. The best-characterized criteria for vitamin
D adequacy are based on randomized clinical trials that show
fracture prevention and preservation of bone mineral density.
Based upon these studies, 25(OH)D concentrations should
exceed 75 nmol/L. This concentration is near the upper end of
the 25(OH)D reference ("normal") range for populations living
in temperate climates, or for people who practice sun-
avoidance, or who wear head coverings. Officially mandated
nutrition guidelines restrict vitamin D intake from fortified
food and supplements to less than 25 mcg/day, a dose
objectively shown to raise serum 25(OH)D in adults by about
25 nmol/L. The combined effect of current nutrition
guidelines and current sun-avoidance advice is to ensure that
adults who follow these recommendations will have 25(OH)D
concentrations lower than 75 nmol/L. Therefore, advice to
avoid UVB light should be accompanied by encouragement to
supplement with vitamin D in an amount that will correct for
the nutrient deficit that sun-avoidance will cause."

Heaney RP, Davies KM, Chen TC, Holick MF, Barger-Lux MJ.
Human serum 25-hydroxycholecalciferol response to extended oral dosing
with cholecalciferol.
Am J Clin Nutr. 2003 Jan;77(1):204-10. Erratum in: Am J Clin Nutr.
2003 Nov;78(5):1047.
PMID: 12499343 [PubMed - indexed for MEDLINE]
<http://www.ajcn.org/cgi/content/full/77/1/204>

"... CONCLUSIONS: Healthy men seem to use 3000-5000 IU
cholecalciferol/d, apparently meeting > 80% of their winter
cholecalciferol need with cutaneously synthesized accumulations
from solar sources during the preceding summer months. Current
recommended vitamin D inputs are inadequate to maintain serum
25-hydroxycholecalciferol concentration in the absence of
substantial cutaneous production of vitamin D."

Hathcock JN, Shao A, Vieth R, Heaney R.
Risk assessment for vitamin D.
Am J Clin Nutr. 2007 Jan;85(1):6-18.
PMID: 17209171 [PubMed - in process]
<http://www.ajcn.org/cgi/content/full/85/1/6>

Vieth R, Chan PC, MacFarlane GD.
Efficacy and safety of vitamin D3 intake exceeding the lowest observed
adverse effect level.
Am J Clin Nutr. 2001 Feb;73(2):288-94.
PMID: 11157326 [PubMed - indexed for MEDLINE]
<http://www.ajcn.org/cgi/content/full/73/2/288>

Vieth R.
Vitamin D supplementation, 25-hydroxyvitamin D concentrations,
andsafety.
Am J Clin Nutr. 1999 May;69(5):842-56. Review.
PMID: 10232622 [PubMed - indexed for MEDLINE]
<http://www.ajcn.org/cgi/content/full/69/5/842>

--
Matti Narkia

From: Matti Narkia on 13 Mar 2007 07:55

On Tue, 13 Mar 2007 13:33:49 +0200, Matti Narkia <mna(a)mbnet.fi> wrote:

>On Mon, 12 Mar 2007 14:53:00 -0500, Ed Friedman <ed(a)math.uchicago.edu>
>wrote:
>
>>Matti Narkia wrote:
>>> 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.
>>
>>Matti,
>>
>>What is the optimum serum level of D3 according to these researchers. I
>>know that the labs around here say "normal" is between the range of 20-75.
>>
>The current consensus among top vitamin D reserchers seems to be that
>the optimal serum calcidiol (25(OH)D) concentration is about 100
>nmol/L. This requires in average perhaps 4000 IU of vitamin D3/d. In
>the winter this is almost impossible to get in the regions outside the
>40th latitudes, so one needs to take supplements in these areas in the
>winter to guarantee optimal vitamin D status. I've been taking 4000
>IU/d in the winter for years.
>
See also

Vitamin D
Micronutrient Information Center - Linus Pauling Institute
<http://lpi.oregonstate.edu/infocenter/vitamins/vitaminD/>

"In general, serum 25(OH)D values less than 20-25 nmol/L
indicate severe deficiency associated with rickets and
osteomalacia (16, 18). Although 50 nmol/L has been suggested
as the low end of the normal range (31), more recent research
suggests that PTH levels (32, 33) and calcium absorption (34)
are not optimized until serum 25(OH)D levels reach
approximately 80 nmol/L . Thus, at least one vitamin D expert
has argued that serum 25(OH)D values less than 80 nmol/L
should be considered deficient (16), while another suggests
that a healthy serum 25(OH)D value is between 75 nmol/L and
125 nmol/L (35)."

Heaney RP, Dowell MS, Hale CA, Bendich A.
Calcium absorption varies within the reference range for serum
25-hydroxyvitamin D.
J Am Coll Nutr. 2003 Apr;22(2):142-6.
PMID: 12672710 [PubMed - indexed for MEDLINE]
<http://www.jacn.org/cgi/content/full/22/2/142>

"In brief, absorption was 65% higher at serum 25OHD levels
averaging 86.5 nmol/L than at levels averaging 50 nmol/L
(both values within the nominal reference range for this
analyte). CONCLUSIONS: Despite the fact that the mean serum
25OHD level in the experiment without supplementation was
within the current reference ranges, calcium absorptive
performance at 50 nmol/L was significantly reduced relative
to that at a mean 25OHD level of 86 nmol/L. Thus, individuals
with serum 25-hydroxyvitamin D levels at the low end of the
current reference ranges may not be getting the full benefit
from their calcium intake. We conclude that the lower end of
the current reference range is set too low."

--
Matti Narkia

From: Matti Narkia on 13 Mar 2007 09:24

From: Matti Narkia on 13 Mar 2007 09:31

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