[Sunflower]

Vitamin D Supplement Doses and Serum 25-Hydroxyvitamin D in the Range Associated with Cancer Prevention

CEDRIC F. GARLAND1, CHRISTINE B. FRENCH2, , LEO L. BAGGERLY3, and ROBERT P. HEANEY4,

"This paper provides a long awaited insight into a dose-response relationship between orally administered vitamin D3 and the resulting levels of serum 25(OH)D in over 3600 citizens. The results will allow new definition of high vitamin D dose safety and reduce concerns about toxicity. This is a landmark contribution in the vitamin D nutrition field!"

Background: Studies indicate that intake of vitamin D in the range from 1,100 to 4,000 IU/d and a serum 25- hydroxyvitamin D concentration [25(OH)D] from 60-80 ng/ml may be needed to reduce cancer risk.

http://www.grassrootshealth.net/garland02-11

Evaluation, Treatment, and Prevention of Vitamin D Deficiency: an Endocrine Society Clinical Practice Guideline 2011

Michael F. Holick, Neil C. Binkley, Heike A. Bischoff-Ferrari,
Catherine M. Gordon, David A. Hanley, Robert P. Heaney,
M. Hassan Murad and Connie M. Weaver

http://jcem.endojournals.org/content/96/7/1911.long

Circulating 25-Hydroxyvitamin D Levels Indicative of Vitamin D Sufficiency: Implications for Establishing a New Effective Dietary Intake Recommendation for Vitamin D1

Bruce W. Hollis2

The current adult recommendations for vitamin D, 200–600 IU/d, are very inadequate when one considers that a 10–15 min whole-body exposure to peak summer sun will generate and release up to 20,000 IU vitamin D-3 into the circulation.

We are now able to better identify sufficient circulating 25(OH)D levels through the use of specific biomarkers that appropriately increase or decrease with changes in 25(OH)D levels; these include intact parathyroid hormone, calcium absorption, and bone mineral density.

Using these functional indicators, several studies have more accurately defined vitamin D deficiency as circulating levels of 25(OH)D ≤ 80 nmol or 32 μg/L.

Recent studies reveal that current dietary recommendations for adults are not sufficient to maintain circulating 25(OH)D levels at or above this level, especially in pregnancy and lactation.

http://jn.nutrition.org/content/135/2/317.short

Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol1,2,3 2005

Robert P Heaney, K Michael Davies, Tai C Chen, Michael F Holick, and
M Janet Barger-Lux

http://ajcn.nutrition.org/content/77/1/204.full

The calculated oral input required to sustain the serum 25-hydroxycholecalciferol concentration present before the study (ie, in the autumn) was 12.5 μg (500 IU)/d, whereas the total amount from all sources (supplement, food, tissue stores) needed to sustain the starting 25-hydroxycholecalciferol concentration was estimated at ≈96 μg (≈3800 IU)/d. By difference, the tissue stores provided ≈78–82 μg/d.

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.

Siehe Graphik hier:

http://ajcn.nutrition.org/content/77/1/2...nsion.html

Mit 1000 I.E. (= 25 µg) VitD3/Tag (2.Kurve von unten nach oben) steigt der 25-OH-VitD3 geringfügig an und bleibt unterhalb des optimalen Bereichs von 75 nmol/l.

Mit 5000 I.E. (=100 µg) VitD3/Tag (3.Kurve von oben nach unten) steigt der VitD3 nach 4-5 Monaten bis zu ca. 150 nmol/l und bleibt danach in diesem optimalen Bereich.

800 I.E. pro Tag...