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Vitamin D and cancer mini-symposium: the risk of additional vitamin D. Vieth R. Ann Epidemiol. 2009 Jul;19(7):441-5. Epub 2009 Apr 11. Review. PMID: 19364661 Conclusion The results of well-conducted trials of vitamin D lead to the conclusion that the current U.S. National Academy of Sciences-Institute of Medicine upper limit for vitamin D intake of 2000IU per day 1, 37 is excessively conservative. That intake would raise serum 25(OH)D by an average of about 50 nmol/L (20 ng/mL), well within the safe range of serum 25(OH)D concentrations that extends to 500 nmol/L (200 ng/mL). Intake of 4,000IU per day would raise serum 25(OH)D by an average of about 100 nmol/L (40 ng/mL). Even prolonged physiologic-replacement intake of 10,000IU per day of vitamin D3 would pose no known risk of adverse effects in virtually all adults.

Estimates of optimal vitamin D status. Dawson-Hughes B, Heaney RP, Holick MF, Lips P, Meunier PJ, Vieth R. Osteoporos Int. 2005 Jul;16(7):713-6. Epub 2005 Mar 18. PMID: 15776217

Long-term effects of giving nursing home residents bread fortified with 125 microg (5000 IU) vitamin D(3) per daily serving. Mocanu V, Stitt PA, Costan AR, Voroniuc O, Zbranca E, Luca V, Vieth R. Am J Clin Nutr. 2009 Apr;89(4):1132-7. Epub 2009 Feb 25. PMID: 19244376 doi:10.3945/ajcn.2008.26890

Knight JA, Lesosky M, Barnett H, Raboud JM, Vieth R. Vitamin D and reduced risk of breast cancer: a population-based case-control study. Cancer Epidemiol Biomarkers Prev. 2007 Mar;16(3):422-9. PMID: 17372236 [PubMed - indexed for MEDLINE]

Hathcock JN, Shao A, Vieth R, Heaney R. \nRisk assessment for vitamin D.\nAm J Clin Nutr. 2007 Jan;85(1):6-18. Review.\nPMID: 17209171 [PubMed - indexed for MEDLINE]

"Under year round UV exposure conditions (low latitudes, broken line, "High UV") there is no association between 25(OH)D and either prostate or pancreatic cancer. At high latitudes (Solid line, "Low UV") there is a positive association between blood levels of 25(OH)D and these cancers. The average year round levels of 25(OH)D actually tend to be higher in northern latitudes, higher than those where there is year-round solar UVB. Vieth explains that we know almost nothing about the enzymes controlling tissue 1,25(OH)2D levels and much of his discussion is extrapolated from renal enzyme activity."

How to optimize vitamin D supplementation to prevent cancer, based on cellular adaptation and hydroxylase enzymology. Vieth R. Anticancer Res. 2009 Sep;29(9):3675-84. Review. PMID: 19667164

The bioavailability of vitamin D from fortified cheeses and supplements is equivalent in adults. Wagner D, Sidhom G, Whiting SJ, Rousseau D, Vieth R. J Nutr. 2008 Jul;138(7):1365-71. PMID: 18567762 Compared with baseline, serum parathyroid hormone decreased with both fortification (P = 0.003) and supplementation (P = 0.012). These data demonstrate that vitamin D is equally bioavailable from fortified hard cheeses and supplements, making cheese suitable for vitamin D fortification.

"I discussed in my last post how Dr Vieth has a model of tissue 1,25(OH)2D synthesis and degradation in which the level of active substance is pretty well independent of blood vitamin D level, provided the level is either rising or stable. I think it is also worth pointing out that he is talking, hypothetically, about tissue 1,25(OH)2D, not plasma level... As we know, almost nothing is known about tissue 1,25(OH)2D control. By Vieth's hypothesis tissue 1,25(OH)2D is OK so long as there is at least SOME vitamin D present in plasma and the level dose not vary too much. Obviously there is a level below which you can have as much of the enzyme for converting vitamin D to the active form as you like, if there is no vitamin D in your blood you can't make any 1,25(OH)2D in your tissues, or in your kidneys for export to your blood to control calcium levels. At the lower extremes we have rickets and osteomalacia. These are clear cut, unarguable markers of vitamin D deficiency, in the absence of confounding factors (there are a few)."

A prospective nested case-control study of vitamin D status and pancreatic cancer risk in male smokers. Stolzenberg-Solomon RZ, Vieth R, Azad A, Pietinen P, Taylor PR, Virtamo J, Albanes D. Cancer Res. 2006 Oct 15;66(20):10213-9. PMID: 17047087 Higher vitamin D concentrations were associated with a 3-fold increased risk for pancreatic cancer (highest versus lowest quintile, >65.5 versus <32.0 nmol/L: OR, 2.92; 95% CI, 1.56-5.48, Ptrend = 0.001) that remained after excluding cases diagnosed early during follow-up. Contrary to expectations, subjects with higher prediagnostic vitamin D status had an increased pancreatic cancer risk compared with those with lower status. Our findings need to be replicated in other populations and caution is warranted in their interpretation and implication. Our results are intriguing and may provide clues that further the understanding of the etiology of this highly fatal cancer. In conclusion, contrary to expectation, subjects with higher 25(OH)D concentrations were at greater risk for pancreatic cancer compared with those with lower concentrations in our prospective study with long-term follow-up. Caution is warranted in the interpretation and implication of our findings, however, as vitamin D inadequacy is an important public health problem and adequate status is desirable to prevent bone and other diseases (5). Our results, however, are intriguing and may provide clues that further the understanding of the etiology of this highly fatal cancer.

How to optimize vitamin D supplementation to prevent cancer, based on cellular adaptation and hydroxylase enzymology. Vieth R. Anticancer Res. 2009 Sep;29(9):3675-84. Review. PMID: 19667164

Vitamin D association with estradiol and progesterone in young women. Knight JA, Wong J, Blackmore KM, Raboud JM, Vieth R. Cancer Causes Control. 2009 Nov 15. [Epub ahead of print] PMID: 19916051 CONCLUSIONS: Higher levels of vitamin D may reduce progesterone and estradiol, providing a potential mechanism for reduction in breast cancer risk from increased vitamin D exposure in young women.

Vitamin D association with estradiol and progesterone in young women. Knight JA, Wong J, Blackmore KM, Raboud JM, Vieth R. Cancer Causes Control. 2009 Nov 15. [Epub ahead of print] PMID: 19916051 Conclusions Higher levels of vitamin D may reduce progesterone and estradiol, providing a potential mechanism for reduction in breast cancer risk from increased vitamin D exposure in young women

"This website is about Vitamin D and MS Multiple sclerosis (MS) is a chronic disease of the central nervous system (CNS), with an uncertain cause. Colleen Hayes and Donald Achaeson have suggested that insufficient sunlight exposure and chronic viral infections might be unrelated environmental risk factors for MS. These risk factors may act synergistically to enable the pathogenic autoimmune response. The prevalence of MS is highest where environmental supplies of vitamin D are lowest. Sunshine enables the production of vitamin D3 (VD3) in the skin. Epidemiological studies have shown that higher vitamin D blood levels are associated with lower risk, less relapses and a slower progression of multiple sclerosis. Higher vitamin D levels can be achieved in part by increased oral intake of VD3. Optimal health requires serum 25 hydroxyvitamin D levels higher than 20 ng/ml (50 nmol/L) P Lips, 40 ng/ml (100 nmol/L) P Heaney or at least 40 ng/ml (100 nmol/L) R Vieth. "

Safety of vitamin D3 in adults with multiple sclerosis. Kimball SM, Ursell MR, O'Connor P, Vieth R. Am J Clin Nutr. 2007 Sep;86(3):645-51. PMID: 17823429 Conclusions: Patients' serum 25(OH)D concentrations reached twice the top of the physiologic range without eliciting hypercalcemia or hypercalciuria. The data support the feasibility of pharmacologic doses of vitamin D3 for clinical research, and they provide objective evidence that vitamin D intake beyond the current upper limit is safe by a large margin.

Assessment of dietary vitamin D requirements during pregnancy and lactation. Hollis BW, Wagner CL. Am J Clin Nutr. 2004 May;79(5):717-26. Review. PMID: 15113709 We found that high-dose maternal vitamin D supplementation not only improves the nutritional vitamin D status of breastfeeding infants but also elevates the maternal concentrations into the mid-normal range. Thus, a dual benefit is achieved from high-dose maternal supplementation. It is noteworthy that in the Finnish study, the authors added a disclaimer, "A sufficient supply of vitamin D to the breastfed infant is achieved only by increasing the maternal supplementation up to 2000 IU/d. Such a dose is far higher than the RDA [DRI] for lactating mothers [and therefore] its safety over prolonged periods is not known and should be examined by further study." This point of concern was valid when this study was conducted in 1986 (92); however, on the basis of the current findings of Vieth et al (2) and of Heaney et al (3)-which showed that vitamin D intakes <= 10 000 IU/d (250 µg) are safe for prolonged periods (up to 5 mo)-we believe that it is time to reexamine the understated DRI of vitamin D for lactating mothers. This work is now being conducted in our clinics and laboratory.

Vieth R, Choo R, Deboer L, Danjoux C, Morton GC, Klotz L. \nRise in prostate-specific antigen in men with untreated low-grade prostate cancer is slower during spring-summer.\nAm J Ther. 2006 Sep-Oct;13(5):394-9.\nPMID: 16988533 [PubMed - indexed for MEDLI

A phase 2 trial exploring the effects of high-dose (10,000 IU/day) vitamin D(3) in breast cancer patients with bone metastases. Amir E, Simmons CE, Freedman OC, Dranitsaris G, Cole DE, Vieth R, Ooi WS, Clemons M. Cancer. 2009 Nov 13. [Epub ahead of print] PMID: 19918922 DOI: 10.1002/cncr.24749 METHODS: Patients with bone metastases treated with bisphosphonates were enrolled into this single-arm phase 2 study. Patients received 10,000 IU of vitamin D3 and 1000 mg of calcium supplementation each day for 4 months. The effect of this treatment on palliation, bone resorption markers, calcium metabolism, and toxicity were evaluated at baseline and monthly thereafter. CONCLUSIONS: Daily doses of 10,000 IU vitamin D3 for 4 months appear safe in patients without comorbid conditions causing hypersensitivity to vitamin D. Treatment reduced inappropriately elevated parathyroid hormone levels, presumably caused by long-term bisphosphonate use. There did not appear to be a significant palliative benefit nor any significant change in bone resorption. Cancer 2010. © 2009 American Cancer Society.

The second committee meeting was held August 4-5, 2009 in Washington, DC and included an Information-Gathering Workshop on August 4, 2009. The agenda for this workshop is below, along with the PowerPoint presentations that were used by the speakers during the workshop. Please note, online presentations from this meeting are subject to copyright protection. Permission from the speaker is required prior to any copying, reproducing, or rebroadcasting any portion of the speaker's presentations. Additional copyright and legal policies of The National Academies can be read in the National Academies Legal Statement.

"We are aware of substantial scientific evidence supporting the role of vitamin D in prevention of cancer. It has been reasonably established that adequate serum vitamin D metabolite levels are associated with substantially lower incidence rates of several types of cancer, including those of the breast, colon, and ovary, and other sites. We have concluded that the vitamin D status of most individuals in North America will need to be greatly improved for substantial reduction in incidence of cancer. Epidemiological studies have shown that higher vitamin D levels are also associated with lower risk of Type I diabetes in children and of multiple sclerosis. Several studies have found that markers of higher vitamin D levels are associated with lower incidence and severity of influenza and several other infectious diseases."