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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

Prostate cancer risk and prediagnostic serum 25-hydroxyvitamin D levels (Finland). Ahonen MH, Tenkanen L, Teppo L, Hakama M, Tuohimaa P. Cancer Causes Control. 2000 Oct;11(9):847-52. PMID: 11075874 DOI: 10.1023/A:1008923802001 CONCLUSIONS: We conclude that low levels of 25-VD associated with an increased risk for subsequent earlier exposure and more aggressive development of prostate cancer, especially before the andropause.

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 doi: 10.1158/0008-5472.CAN-06-1876 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.

Prevention of nonvertebral fractures with oral vitamin D and dose dependency: a meta-analysis of randomized controlled trials. Bischoff-Ferrari HA, Willett WC, Wong JB, Stuck AE, Staehelin HB, Orav EJ, Thoma A, Kiel DP, Henschkowski J. Arch Intern Med. 2009 Mar 23;169(6):551-61. PMID: 19307517 Conclusion Nonvertebral fracture prevention with vitamin D is dose dependent, and a higher dose should reduce fractures by at least 20% for individuals aged 65 years or older.

Vitamin D supplementation to prevent infections: a sub-study of a randomised placebo-controlled trial in older people (RECORD trial, ISRCTN 51647438).\nAvenell A, Cook JA, Maclennan GS, Macpherson GC.\nAge Ageing. 2007 Sep;36(5):574-7. Epub 2007 Aug 15. No abstract available.\nPMID: 17702768 \ndoi:10.1093/ageing/afm091

Schleithoff SS, Zittermann A, Tenderich G, Berthold HK, Stehle P, Koerfer R. Vitamin D supplementation improves cytokine profiles in patients with congestive heart failure: a double-blind, randomized, placebo-controlled trial.Am J Clin Nutr. 2006 Apr;

van der Mei IA, Ponsonby AL, Dwyer T, Blizzard L, Taylor BV, Kilpatrick T, Butzkueven H, McMichael AJ. Vitamin D levels in people with multiple sclerosis and community controls in Tasmania, Australia. J Neurol. 2007 May;254(5):581-90. Epub 2007 Apr 11.

A nested case control study of plasma 25-hydroxyvitamin D concentrations and risk of colorectal cancer. Wu K, Feskanich D, Fuchs CS, Willett WC, Hollis BW, Giovannucci EL. J Natl Cancer Inst. 2007 Jul 18;99(14):1120-9. Epub 2007 Jul 10. PMID: 17623801

Vitamin D supplementation reduces insulin resistance in South Asian women living in New Zealand who are insulin resistant and vitamin D deficient - a randomised, placebo-controlled trial. von Hurst PR, Stonehouse W, Coad J. Br J Nutr. 2009 Sep 28:1-7. [Epub ahead of print] PMID: 19781131 In conclusion, improving vitamin D status in insulin resistant women resulted in improved IR and sensitivity, but no change in insulin secretion. Optimal vitamin D concentrations for reducing IR were shown to be 80-119 nmol/l, providing further evidence for an increase in the recommended adequate levels. Registered Trial No. ACTRN12607000642482.

Correlation of symptoms with vitamin D deficiency and symptom response to cholecalciferol treatment: a randomized controlled trial. Arvold DS, Odean MJ, Dornfeld MP, Regal RR, Arvold JG, Karwoski GC, Mast DJ, Sanford PB, Sjoberg RJ. Endocr Pract. 2009 May-Jun;15(3):203-12. PMID: 19364687 Conclusions: Compared with participants in the placebo group, patients in the treatment group showed mild short-term improvement in the overall fibromyalgia impact score, but did not show significant improvement in most musculoskeletal symptoms or in activities of daily living.

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.

Fall prevention with supplemental and active forms of vitamin D: a meta-analysis of randomised controlled trials. Bischoff-Ferrari HA, Dawson-Hughes B, Staehelin HB, Orav JE, Stuck AE, Theiler R, Wong JB, Egli A, Kiel DP, Henschkowski J. BMJ. 2009 Oct 1;339:b3692. doi: 10.1136/bmj.b3692. PMID: 19797342 doi: 10.1136/bmj.b3692 Conclusions Supplemental vitamin D in a dose of 700-1000 IU a day reduced the risk of falling among older individuals by 19% and to a similar degree as active forms of vitamin D. Doses of supplemental vitamin D of less than 700 IU or serum 25-hydroxyvitamin D concentrations of less than 60 nmol/l may not reduce the risk of falling among older individuals.

Effect of four monthly oral vitamin D3 (cholecalciferol) supplementation on fractures and mortality in men and women living in the community: randomised double blind controlled trial. Trivedi DP, Doll R, Khaw KT. BMJ. 2003 Mar 1;326(7387):469. PMID: 12609940 Conclusion: Four monthly supplementation with 100 000 IU oral vitamin D may prevent fractures without adverse effects in men and women living in the general community.

Inverse association between serum 25(OH) vitamin D levels and non-melanoma skin cancer in elderly men. Tang JY, Parimi N, Wu A, John Boscardin W, Shikany JM, Chren MM, Cummings SR, Epstein EH Jr, Bauer DC; for the Osteoporotic Fractures in Men (MrOS) Study Group. Cancer Causes Control. 2009 Nov 18. [Epub ahead of print] PMID: 19921445 Our results suggest that a diagnosis of NMSC is not a surrogate for adequate 25(OH)D levels or increased UV exposure, and high 25(OH)D levels may be associated with a reduced risk of NMSC.

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

Vitamin D replacement in Asians with diabetes may increase insulin resistance. Taylor AV, Wise PH. Postgrad Med J. 1998 Jun;74(872):365-6. PMID: 9799895 We report three cases of vitamin D replacement in British Asians with vitamin D deficiency and non-insulin-dependent diabetes mellitus. In all cases, replacement resulted in an increase in insulin resistance and a deterioration of glycaemic control

25-Hydroxyvitamin D and functional outcomes in adolescents. Lamberg-Allardt CJ, Viljakainen HT. Am J Clin Nutr. 2008 Aug;88(2):534S-536S. Review. PMID: 18689396 CONCLUSIONS Cross-sectional studies have shown a relation among serum 25(OH)D concentration, serum PTH concentration, and BMD in adolescents. Long-term randomized controlled intervention studies have shown that vitamin D3 supplementation has a positive effect on BMD in adolescence; some of these studies found an effect with doses as small as 5 µg (200 IU) to 10 µg (400 IU) per day, or without supplemental calcium.

Annual intramuscular injection of a megadose of cholecalciferol for treatment of vitamin D deficiency: efficacy and safety data. Diamond TH, Ho KW, Rohl PG, Meerkin M. Med J Aust. 2005 Jul 4;183(1):10-2. PMID: 15992330 Conclusions: Once-yearly intramuscular cholecalciferol injection (600 000 IU) is effective therapy for vitamin D deficiency. While this therapy appears to be safe, the potential for developing hypercalciuria needs to be examined in a large randomised controlled trial.

Nutrients, endpoints, and the problem of proof. Heaney RP. 2008 W. O. Atwater Memorial Lecture J Nutr. 2008 Sep;138(9):1591-5. PMID: 18716155 To sum up, I think that there would be general agreement to the effect that nutrition is important, despite the fact that the still growing number of failed trials of individual nutrients might suggest that no nutrient actually made much of a difference, a conclusion that is absurd on its face and ought to have alerted us to the possibility that there was something wrong with how we were investigating the matter. To provide the proof needed to sustain revised intake recommendations, we shall have to find a design better suited to nutrients than the randomized controlled trial as currently implemented, and we need to develop a series of global indices, nutrient by nutrient, which better capture the polyvalent nature of most nutrients. Perhaps it would be useful for the ASN, in collaboration with concerned governmental entities such as the USDA, to convene a workshop to address these structural issues. Such deliberation may well be arduous and frustrating, but it is terribly important and, in my view, well worth the effort.