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The Linus Pauling Institute's Micronutrient Information Center is a source for scientifically accurate information regarding the roles of vitamins, minerals, other nutrients, dietary phytochemicals (plant chemicals that may affect health), and some foods

Intake of vitamin D and risk of type 1 diabetes: a birth-cohort study. Hyppönen E, Läärä E, Reunanen A, Järvelin MR, Virtanen SM. Lancet. 2001 Nov 3;358(9292):1500-3. PMID: 11705562 doi:10.1016/S0140-6736(01)06580-1 INTERPRETATION: Dietary vitamin D supplementation is associated with reduced risk of type 1 diabetes. Ensuring adequate vitamin D supplementation for infants could help to reverse the increasing trend in the incidence of type 1 diabetes.

Vitamin D intake is low and hypovitaminosis D common in healthy 9- to 15-year-old Finnish girls. Lehtonen-Veromaa M, Möttönen T, Irjala K, Kärkkäinen M, Lamberg-Allardt C, Hakola P, Viikari J. Eur J Clin Nutr. 1999 Sep;53(9):746-51. PMID: 10509773 CONCLUSION: Hypovitaminosis D is fairly common in growing Finnish girls in the wintertime, and three months of vitamin D supplementation with 10 microg/d was insufficient in preventing hypovitaminosis D. The daily dietary vitamin D intake was insufficient (< 5 microg/d) in the majority of participants, while the calcium intake was usually sufficient.

Geographic variation in breast cancer mortality in the United States: a hypothesis involving exposure to solar radiation. Garland FC, Garland CF, Gorham ED, Young JF. Prev Med. 1990 Nov;19(6):614-22. PMID: 2263572 doi:10.1016/0091-7435(90)90058-R Vitamin D from sunlight exposure may be associated with low risk for fatal breast cancer, and differences in ultraviolet light reaching the United States population may account for the striking regional differences in breast cancer mortality. The ecological nature of this study is emphasized, and the possibility that an indirect association with dietary and socioeconomic factors could explain these findings is discussed.

van der Wielen RP, Lowik MR, van den BH, de Groot LC, Haller J, Moreiras O, van Staveren WA (1995) Serum vitamin D concentrations among elderly people in Europe. Lancet 346: 207-210 These findings show that free-living elderly Europeans, regardless of geographical location, are at substantial risk of inadequate vitamin D status during winter and that dietary enrichment or supplementation with vitamin D should be seriously considered during this season.

Serum 25-hydroxyvitamin D concentration and subsequent risk of type 2 diabetes. Mattila C, Knekt P, Männistö S, Rissanen H, Laaksonen MA, Montonen J, Reunanen A. Diabetes Care. 2007 Oct;30(10):2569-70. Epub 2007 Jul 12. PMID: 17626891 doi: 10.2337/dc07-0292 We found a significant inverse association between serum 25OHD and risk of type 2 diabetes in the simple model. However, the association was attenuated in the multivariate analysis, adjusting for potential risk factors of type 2 diabetes. To our knowledge, this is the first cohort study investigating the association between serum 25OHD and incidence of type 2 diabetes. Our results are in line with those from the Nurses' Health Study (5), where an inverse association was observed for the intake of vitamin D supplements. We could not differentiate whether the results depended on the effect of vitamin D deficiency on β-cell function or on insulin resistance. In summary, the results are in line with the hypothesis that a high serum 25OHD concentration may reduce the risk of type 2 diabetes. Further research is needed to confirm the association and to distinguish between the independent role of vitamin D and the role of healthy dietary and lifestyle patterns in reducing the risk of type 2 diabetes.

Vitamin D is associated with improved survival in early-stage non-small cell lung cancer patients. Zhou W, Suk R, Liu G, Park S, Neuberg DS, Wain JC, Lynch TJ, Giovannucci E, Christiani DC. Cancer Epidemiol Biomarkers Prev. 2005 Oct;14(10):2303-9. PMID: 16214909 In conclusion, the joint effects of surgery season and recent vitamin D intake seem to be associated with the survival of early-stage non-small cell lung cancer patients. In summary, for early-stage NSCLC patients, patients who had surgery in summer with "high" recent vitamin D intake have a statistically significantly improved RFS and OS than patients who had surgery in winter with "low" vitamin D intake. These results should be confirmed in a prospective study to assess the serum vitamin D levels at time of surgery. If the results are confirmed, our results, combined with findings in other studies, suggest that dietary vitamin D supplementation may be advisable for early stages of lung cancer patients, particularly during the winter season and in groups that tend to be deficient in vitamin D.

Comment: The strengths of this randomized study include its high level of adherence and its use of a vitamin D dose sufficient to cause a biologically meaningful increase in serum levels. The adult daily value for vitamin D is 400 IU, but many U.S. women are vitamin-D-deficient (N Engl J Med 2007; 357:266). The Institute of Medicine considers doses up to 2000 IU to be without significant risk for adverse health effects. In addition to consuming dietary sources of vitamin D (see Table 1), most women will need supplements to achieve adequate intake. Multivitamins usually contain 400 IU of vitamin D.

Comment: Although lower risk associated with vitamin D exposure was shown most consistently for ER+/PR+ tumors, the result might simply reflect that this tumor subtype was the most common. Nonetheless, these findings support vitamin D's beneficial effects on breast cancer risk, regardless of hormone-receptor status. Sun exposure and dietary intake (Table 1) are key sources of vitamin D.

A multicountry ecologic study of risk and risk reduction factors for prostate cancer mortality. Grant WB. Eur Urol. 2004 Mar;45(3):271-9. PMID: 15036670 CONCLUSIONS: These results are consistent with insulin-like growth factor-I (IGF-I), being an important risk factor for prostate cancer, with alcohol and calcium being less important risk factors, and with allium family vegetables, and, to a lesser extent, vitamin D being important risk reduction factors. These results should provide guidance for additional studies on dietary and environmental links to prostate cancer.

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.

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.

High prevalence of vitamin D deficiency despite supplementation in premenopausal women with breast cancer undergoing adjuvant chemotherapy. Crew KD, Shane E, Cremers S, McMahon DJ, Irani D, Hershman DL. J Clin Oncol. 2009 May 1;27(13):2151-6. Epub 2009 Apr 6. PMID: 19349547 DOI: 10.1200/JCO.2008.19.6162 Conclusion Vitamin D deficiency is highly prevalent in women with breast cancer. The current recommended dietary allowance of vitamin D is too low to increase serum 25-OHD greater than 30 ng/mL. Optimal dosing for bone health and, possibly, improved survival has yet to be determined.

Vitamin D plays a critical role in the human body's response to tuberculosis, according to new research that explains why people of African descent are more susceptible to TB. The research also suggests a new way to fight one of the world's deadliest diseases: with a simple dietary supplement. Tuberculosis, usually caused when a person inhales tuberculosis bacteria, killed an estimated 1.7 million people in 2003 and is the leading cause of death for people afflicted with AIDS, according to the World Health Organization (WHO).

Prevalence of vitamin D insufficiency in Brazilian adolescents. Peters BS, dos Santos LC, Fisberg M, Wood RJ, Martini LA. Ann Nutr Metab. 2009;54(1):15-21. Epub 2009 Feb 5. PMID: 19194104 DOI: 10.1159/000199454 CONCLUSIONS: The present study suggests that even in a sunny climate like Brazil the prevalence of vitamin D insufficiency in adolescents is high. Most likely this is due to low intakes of vitamin D in this group. Due to the limited extent of natural dietary sources of vitamin D, a policy of vitamin D food fortification should be considered in the future, and in the meantime greater use of vitamin D supplements in this population group should be encouraged to provide the increased amounts of this essential nutrient for optimal health.

What is VITAL? The VITamin D and OmegA-3 TriaL (VITAL) is a research study in 20,000 U.S. men and women investigating whether taking daily dietary supplements of vitamin D (about 2000 IU) or fish oil (about 1 gram of omega-3 fatty acids) reduces the risk of developing cancer, heart disease, and stroke in people who do not have a prior history of these illnesses. Recruitment for the study will begin in January 2010.

Vitamin D: a D-Lightful health perspective. Holick MF. Nutr Rev. 2008 Oct;66(10 Suppl 2):S182-94. Review. PMID: 18844847 DOI: 10.1111/j.1753-4887.2008.00104.x Sunlight provides most humans with their vitamin D requirement. Adequate vitamin D(3) by synthesis in the skin or from dietary and supplemental sources is essential for bone health throughout life. Vitamin D deficiency is defined as a 25(OH)D concentration 30 ng/mL (75 nmol/L), and insufficiency as 21-29 ng/mL. Vitamin D deficiency and insufficiency has been linked to a wide variety of chronic diseases including common cancers, autoimmune, cardiovascular, and infectious diseases. Healthcare professionals need to be aware of the vitamin D deficiency pandemic. Guidelines for sensible sun exposure and supplemental vitamin D of 800-1000 IU/day are needed.

Benefits of Vitamin D Supplementation Joel M. Kauffman, Ph.D. Journal of American Physicians and Surgeons Volume 14 Number 2 - Summer 2009 Clinical trials show that vitamin D supplementation at higher levels than previously recommended is beneficial for many conditions. It decreases the frequency of falls and fractures, helps prevent cardiovascular disease, and reduces symptoms of colds or influenza. Benefits are also seen in diabetes mellitus, multiple sclerosis, Crohn disease, pain, depression, and possibly autism. Sunlight does not cause an overdose of vitamin D production, and toxicity from supplementation is rare. Dose recommendations are increasing, but appear to be lagging the favorable trial results. A number of common drugs deplete vitamin D levels, and others may limit its biosynthesis from sunlight. People with adequate levels from sun exposure will not benefit from supplementation. While dietary intake is helpful, supplementation is better able to raise serum 25-hydroxyvitamin D , the major circulating metabolite, to the level now thought adequate, 30-50 ng/mL. Where there is inadequate daily sun exposure, oral doses of 1,000-2,000 IU/d are now considered routine, with much higher doses (up to 50,000 IU) for rapid repletion now considered safe.

Are statins analogues of vitamin D? Grimes DS. Lancet. 2006 Jul 1;368(9529):83-6. Review. PMID: 16815382 doi:10.1016/S0140-6736(06)68971-X There are many reasons why the dietary-heart-cholesterol hypothesis should be questioned, and why statins might be acting in some other way to reduce the risk of coronary heart disease. Here, I propose that rather than being cholesterol-lowering drugs per se, statins act as vitamin D analogues, and explain why. This proposition is based on published observations that the unexpected and unexplained clinical benefits produced by statins have also been shown to be properties of vitamin D. It seems likely that statins activate vitamin D receptors.