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Effectiveness and safety of vitamin D in relation to bone health. Cranney A, Horsley T, O'Donnell S, Weiler H, Puil L, Ooi D, Atkinson S, Ward L, Moher D, Hanley D, Fang M, Yazdi F, Garritty C, Sampson M, Barrowman N, Tsertsvadze A, Mamaladze V. Evid Rep Technol Assess (Full Rep). 2007 Aug;(158):1-235. Review. PMID: 18088161 CONCLUSIONS: The results highlight the need for additional high quality studies in infants, children, premenopausal women, and diverse racial or ethnic groups. There was fair evidence from studies of an association between circulating 25(OH)D concentrations with some bone health outcomes (established rickets, PTH, falls, BMD). However, the evidence for an association was inconsistent for other outcomes (e.g., BMC in infants and fractures in adults). It was difficult to define specific thresholds of circulating 25(OH)D for optimal bone health due to the imprecision of different 25(OH)D assays. Standard reference preparations are needed so that serum 25(OH)D can be accurately and reliably measured, and validated. In most trials, the effects of vitamin D and calcium could not be separated. Vitamin D(3) (>700 IU/day) with calcium supplementation compared to placebo has a small beneficial effect on BMD, and reduces the risk of fractures and falls although benefit may be confined to specific subgroups. Vitamin D intake above current dietary reference intakes was not reported to be associated with an increased risk of adverse events. However, most trials of higher doses of vitamin D were not adequately designed to assess long-term harms.

Plasma 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D and risk of incident ovarian cancer. Tworoger SS, Lee IM, Buring JE, Rosner B, Hollis BW, Hankinson SE. Cancer Epidemiol Biomarkers Prev. 2007 Apr;16(4):783-8. PMID: 17416771 doi: 10.1158/1055-9965.EPI-06-0981 Overall, our results do not suggest that plasma vitamin D levels are associated with risk of ovarian cancer. However, we observed significant associations in some subgroups, which should be evaluated further in other studies because increasing vitamin D intake is an easy preventive measure to adopt.

Vitamin D may suppress infections which lead to development of Multiple Sclerosis Steven R Brenner, None (16 August 2007) J Neurol Neurosurg Psychiatry 2008 I read the article with reference to the inverse relationship between multiple sclerosis clinical activity and deficiency of vitamin D by Soilu-Hannienen (1) with interest, and was considering what mechanism could be in play to cause such a relationship. 25-hydroxylated metabolites of vitamin D act as intracellular regulators of the synthesis and action of defensin (2) molecules against bacterial antigens, defensin being an endogenously synthesized antimicrobial substance (2). Human cathelicidin antimicrobial peptide gene is a target of vitamin D receptor and is strongly up-regulated by 1,25-dihydroxyvitamin D3, indicating vitamin D receptor and the 1,25-dihydroxyvitaminD3 regulate primate innate immunity (3)

Incidence of reported cold/influenza symptoms according to season. The 104 subjects in the placebo group (light shade) reported cold and flu symptoms year around with the most symptoms in the winter. While on 800 IU per day (intermediate shade) the 104 test subjects were as likely to get sick in the summer as the winter. Only one of the 104 test subjects had cold/influenza symptoms during the final year of the trial, when they took 2,000 IU of vitamin D per day (dark shading). Adapted from: Aloia JF, Li-Ng M: Epidemic influenza and vitamin D. Epidemiol Infect 2007; 135: 1095-1096

Conclusion The data point to a critical role for the VDR and 1,25(OH)2D3 in control of innate immunity and the response of the colon to chemical injury. Vitamin D and the vitamin D receptor are critical for control of the innate immune response to colonic injury. Froicu M, Cantorna MT. BMC Immunol. 2007 Mar 30;8:5. PMID: 17397543 doi:10.1186/1471-2172-8-5

Vitamin D supplementation. Eveleigh B. Can Fam Physician. 2007 Sep;53(9):1435; author reply 1435. PMID: 17872869 My concern regarding vitamin D2 is that it is a synthetic analogue and might interact with the vitamin D receptor differently in various cell systems. It has been reported that vitamin D3 might improve glycemic control.7 Vitamin D2 has been reported to cause worsening of glycemic control in people of East Indian descent.8 Is this because of vitamin D receptor polymorphism, or because of enhanced 24-hydroxylase enzyme activation, or is it due to how vitamin D2 interacts with the receptor? Until this has been sorted out, I feel safest using vitamin D3. There are about 2000 synthetic analogues of vitamin D. The search is on for one that can cross the blood-brain barrier to treat certain types of brain cancers without causing hypercalcemia.9 But then again, what other effects would this compound have? There are still so many unknowns

Not enough vitamin D: health consequences for Canadians. Schwalfenberg G. Can Fam Physician. 2007 May;53(5):841-54. Review PMID: 17872747 Conclusion Low levels of VTD are considered a major public health problem in Canada, especially during the winter. Those with risk factors should be screened for low 25(OH)D levels and repletion therapy instituted if needed. Researchers have estimated that the oral dose of vitamin D3 to attain and maintain 25(OH)D levels >80 nmol/L is 2200 IU/d if baseline levels are 20 to 40 nmol/L, 1800 IU/d if levels are 40 to 60 nmol/L, and 1160 IU/d if levels are between 60 and 80 nmol/L.64 We need to ensure that patients have healthy blood levels of 25(OH)D to prevent levels of parathyroid hormone from rising and to maximize absorption of calcium, magnesium, and phosphate. Positive effects on bone are marginal at best unless patients consume at least 800 IU/d of VTD. The emerging and exciting role of the VTD receptor and the actions of VTD in maintaining health in other cell types have become more apparent during the last decade.

Evidence-based decision making on micronutrients and chronic disease: long-term randomized controlled trials are not enough. Ames BN, McCann JC, Stampfer MJ, Willett WC. Am J Clin Nutr. 2007 Aug;86(2):522-3; author reply 523-4. PMID: 17684228

Are sunlight deprivation and influenza epidemics associated with the onset of acute leukemia? Timonen T, Näyhä S, Koskela T, Pukkala E. Haematologica. 2007 Nov;92(11):1553-6. PMID: 18024404 doi:10.3324/haematol.10799 Month of diagnosis of 7,423 cases of acute leukemia (AL) in Finland during 1964-2003 were linked with data on influenza and solar radiation. Acute myeloblastic leukemia (AML) showed the highest risk in the dark season. During the light season, the incidence decreased by 58% (95% confidence interval, 16-79%) per 1,000 kJ/m2/d increase of solar radiation. Independent of solar radiation, AML increased by 9% (95% confidence interval, 0-19%) during influenza epidemics. Reoccurring at the same time annually, darkness-related vitamin D deficiency and influenza could cause successive and co-operative mutations leading to AL with a short latency.

Vitamin D toxicity, policy, and science. Vieth R. J Bone Miner Res. 2007 Dec;22 Suppl 2:V64-8. Review. PMID: 18290725 doi: 10.1359/jbmr.07s221

Vitamin D and skin physiology: a D-lightful story.\nHolick MF, Chen TC, Lu Z, Sauter E.\nJ Bone Miner Res. 2007 Dec;22 Suppl 2:V28-33.\nPMID: 18290718 \ndoi: 10.1359/jbmr.07s211\n

Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. Lappe JM, Travers-Gustafson D, Davies KM, Recker RR, Heaney RP. Am J Clin Nutr. 2007 Jun;85(6):1586-91. Erratum in: Am J Clin Nutr. 2008 Mar;87(3):794. PMID: 17556697 Conclusions: Improving calcium and vitamin D nutritional status substantially reduces all-cancer risk in postmenopausal women.

Genetic and non-genetic correlates of vitamins K and D.\nShea MK, Benjamin EJ, Dupuis J, Massaro JM, Jacques PF, D'Agostino RB Sr, Ordovas JM, O'Donnell CJ, Dawson-Hughes B, Vasan RS, Booth SL.\nEur J Clin Nutr. 2007 Nov 21. [Epub ahead of print]\nPMID: 18030310 \ndoi: 10.1038/sj.ejcn\n\n

Reginster JY. Prevalence of vitamin D inadequacy in European postmenopausal women. Curr Med Res Opin. 2007 Jul 12; [Epub ahead of print] PMID: 17631697 [PubMed - as supplied by publisher]

Gonzalez G, Alvarado JN, Rojas A, Navarrete C, Velasquez CG, Arteaga E. High prevalence of vitamin D deficiency in Chilean healthy postmenopausal women with normal sun exposure: additional evidence for a worldwide concern. Menopause. 2007 May-Jun;14(3

Gorham ED, Garland CF, Garland FC, Grant WB, Mohr SB, Lipkin M, Newmark HL, Giovannucci E, Wei M, Holick MF. Optimal vitamin D status for colorectal cancer prevention: a quantitative meta analysis. Am J Prev Med. 2007 Mar;32(3):210-6. PMID: 17296473

Zittermann A, Schleithoff SS, Koerfer R. \nVitamin D and vascular calcification.\nCurr Opin Lipidol. 2007 Feb;18(1):41-6. Review.\nPMID: 17218831 [PubMed - indexed for MEDLINE

Vitamin D fortification of milk products does not resolve hypovitaminosis D in young Finnish men. Välimäki VV, Löyttyniemi E, Välimäki MJ. Eur J Clin Nutr. 2007 Apr;61(4):493-7. Epub 2006 Nov 29. PMID: 17136043 doi:10.1038/sj.ejcn.1602550

The Vitamin D Pandemic and its Health Consequences\nPresented by Michael Holick, PhD, MD, Professor of medicine, physiology and biophysics and director of the General Clinical Research Center at Boston University Medical Center\nKeynote address at the opening ceremony of the 34th European Symposium on Calcified Tissues, Copenhagen 5 May, 2007\n

Concentrations of vitamin D3 and 25-hydroxyvitamin D3 in raw and cooked New Zealand beef and lamb. Roger Purchas, Maggie Zoua, Philip Pearcea and Felicity Jackson- Journal of Food Composition and Analysis Volume 20, Issue 2, March 2007, Pages 90-98 For lamb, the highest levels of vitamin D3 were in the shoulder chop both before and after cooking, while levels were lowest in the rack muscle. Similar cut differences were shown for 25OHD3 concentrations. For beef there were no significant differences between the cuts for vitamin D3, but concentrations of 25OHD3 were lower in the striploin before and after cooking, Vitamin D3 levels tended to be higher in beef cuts than in lamb cuts, but the opposite held for 25OHD3. Concentrations of vitamin D3 were similar to those in other reports, but the 25OHD3 levels were at the high end of reported ranges. With 25OHD3 being more potent than vitamin D3, it is concluded that meat can make a useful contribution of this vitamin to the human diet.