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Plasma 25-hydroxyvitamin D levels and risk of incident hypertension among young women. Forman JP, Curhan GC, Taylor EN. Hypertension. 2008 Nov;52(5):828-32. Epub 2008 Oct 6. PMID: 18838623 doi: 10.1161/HYPERTENSIONAHA.108.117630 Women in the lowest compared with highest quartile of plasma 25(OH)D had an adjusted odds ratio for incident hypertension of 1.66 (95% CI: 1.11 to 2.48; P for trend=0.01). Compared with women with sufficient levels, those with vitamin D deficiency (<30 ng/mL; 65.7% of the study population) had a multivariable odds ratio of 1.47 (95% CI: 1.10 to 1.97). Plasma 25(OH)D levels are inversely and independently associated with the risk of developing hypertension.

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. Circulating 25-hydroxyvitamin D levels indicative of vitamin D sufficiency: implications for establishing a new effective dietary intake recommendation for vitamin D. Hollis BW. J Nutr. 2005 Feb;135(2):317-22. Review. PMID: 15671234 [

Why is it that vitamin D deficiency can manifest in so many different ways in different people? One big reason is something called vitamin D receptor (VDR) genotypes, the variation in the receptor for vitamin D. Why is it that the dose of vitamin D necessary to reach a specific level differs so widely from one person to the next? VDR genotype, again. Variation in blood levels of 25-hydroxy vitamin D from a specific dose of vitamin D can vary three-fold, as shown by a University of Toronto study. In other words, a dose of 4000 units per day may yield a 25-hydroxy vitamin D blood level of 30 ng/ml in Mary, 60 ng/ml in Paul, and 90 ng/ml in Pete--same dose, different blood levels

Vieth R, Chan PC, MacFarlane GD.Efficacy and safety of vitamin D3 intake exceeding the lowest observedadverse effect level.Am J Clin Nutr. 2001 Feb;73(2):288-94.PMID: 11157326 [PubMed - indexed for MEDLINE]

Use of vitamin D in clinical practice. Cannell JJ, Hollis BW. Altern Med Rev. 2008 Mar;13(1):6-20. PMID: 18377099 The recent discovery--from a meta-analysis of 18 randomized controlled trials--that supplemental cholecalciferol (vitamin D) significantly reduces all-cause mortality emphasizes the medical, ethical, and legal implications of promptly diagnosing and adequately treating vitamin D deficiency. Not only are such deficiencies common, and probably the rule, vitamin D deficiency is implicated in most of the diseases of civilization. Vitamin D's final metabolic product is a potent, pleiotropic, repair and maintenance, seco-steroid hormone that targets more than 200 human genes in a wide variety of tissues, meaning it has as many mechanisms of action as genes it targets. One of the most important genes vitamin D up-regulates is for cathelicidin, a naturally occurring broad-spectrum antibiotic. Natural vitamin D levels, those found in humans living in a sun-rich environment, are between 40-70 ng per ml, levels obtained by few modern humans. Assessing serum 25-hydroxy-vitamin D (25(OH)D) is the only way to make the diagnosis and to assure treatment is adequate and safe. Three treatment modalities exist for vitamin D deficiency: sunlight, artificial ultraviolet B (UVB) radiation, and vitamin D3 supplementation. Treatment of vitamin D deficiency in otherwise healthy patients with 2,000-7,000 IU vitamin D per day should be sufficient to maintain year-round 25(OH)D levels between 40-70 ng per mL. In those with serious illnesses associated with vitamin D deficiency, such as cancer, heart disease, multiple sclerosis, diabetes, autism, and a host of other illnesses, doses should be sufficient to maintain year-round 25(OH)D levels between 55 -70 ng per mL. Vitamin D-deficient patients with serious illness should not only be supplemented more aggressively than the well, they should have more frequent monitoring of serum 25(OH)D and serum calcium. Vitamin D should always be

An estimated 50% to 60% of older people have suboptimal vitamin D levels, which is a problem that could affect more than bone health. Recent cross-sectional studies have also shown an association between low vitamin D levels and cardiovascular disease, hypertension, and metabolic syndrome. In a long-term prospective study from Germany, researchers assessed whether 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels were associated with all-cause and cardiovascular mortality among more than 3000 consecutive patients (mean age, 62) referred for coronary angiography.

NEW YORK (Reuters Health) - New research suggests that low vitamin D levels in the body are associated with thinking or "cognitive" impairments in older men, but whether vitamin D supplements can help is not yet known. In the study, an investigation of European men, subjects with low levels of vitamin D scored worse on a standard test of cognitive ability than did their peers with normal levels, Dr. David M. Lee, from the University of Manchester, UK, and co-researchers found. Although, the authors emphasize, the difference in scores was not that great.

Hypovitaminosis D in British adults at age 45 y: nationwide cohort study of dietary and lifestyle predictors. Hyppönen E, Power C. Am J Clin Nutr. 2007 Mar;85(3):860-8. PMID: 17344510 Conclusion: Prevalence of hypovitaminosis D in the general population was alarmingly high during the winter and spring, which warrants action at a population level rather than at a risk group level. Data from the 1958 birth cohort suggest that, at different cutoffs for hypovitaminosis D, a substantial public health problem exists in British whites. Obese participants and those living in Scotland were at the highest risk of hypovitaminosis D. However, the prevalence in the general population was very high during the winter and spring, which suggests that, to improve the situation, action is required at a population level rather than at a risk-group level. In the United States, calls have gone out for an increase in vitamin D fortification of foods (11), and the data from the current study suggest that such action is also warranted in the United Kingdom. Vitamin D is currently available without prescription as a dietary supplement only as part of cod liver oil or multivitamin products; hence, a need clearly exists to consider increased availability of over-the-counter supplements. Hypovitaminosis D has been implicated in the development of serious conditions, including diabetes, various types of cancer, and cardiovascular diseases, in addition to its essential role in maintaining bone health (1, 2). The high rates of hypovitaminosis D reported in this study suggest that immediate action is needed to improve the vitamin D status of the British population.

Serum levels of free 1,25-dihydroxyvitamin D in vitamin D toxicity. Pettifor JM, Bikle DD, Cavaleros M, Zachen D, Kamdar MC, Ross FP. Ann Intern Med. 1995 Apr 1;122(7):511-3. PMID: 7872586 CONCLUSIONS: Although the patients had normal or near-normal total 1,25-(OH)2D values, most patients had elevated free 1,25-(OH)2D levels. These findings suggest that elevated free 1,25-(OH)2D levels might play a role in the pathogenesis of hypercalcemia in vitamin D toxicity.

San Diego, CA (PRWEB) May 25, 2009 -- Coming on the heels of the publishing in the Annals of Epidemiology of a new study led by Dr. Cedric Garland, on the preventive measures of vitamin D, GrassrootsHealth D*action Project is calling on physicians, health clinics and groups throughout the country to recognize the need for determining vitamin D levels and to ensure the public have their blood levels of vitamin D tested. According to research from the newly published study by Cedric F. Garland, Dr. P.H., FACE, Department of Family and Preventive Medicine and Moores Cancer Center of the University of California, San Diego (UCSD), "It is projected that raising the minimum year-around serum 25(OH)D level to 40-60 ng/ml (100-150 nmol/L) would prevent approximately 58,000 new cases of breast cancer and 49,000 new cases of colorectal cancer each year, and three quarters of deaths from these diseases, in the US and Canada."

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.

Relationships between 25-Hydroxyvitamin D Levels and Plasma Glucose and Lipid Levels in Pediatric Outpatients. Johnson MD, Nader NS, Weaver AL, Singh R, Kumar S. J Pediatr. 2009 Nov 17. [Epub ahead of print] PMID: 19926097 Conclusions Low 25(OH) D levels in children and adolescents are associated with higher plasma glucose and lower HDL concentrations.

"It's well known that African Americans have low levels of vitamin D in their blood. In fact, this seems to be generally true for humans of tropical origin. In a study from Hawaii, vitamin D status was assessed in healthy, visibly tanned young adults who averaged 22.4 hours per week of unprotected sun exposure. Yet 51% had levels below the current recommended minimum of 75 nmol/L (Binkley et al., 2007). In a study from south India, levels below 50 nmol/L were found in 44% of the men and 70% of the women. The subjects are described as "agricultural workers starting their day at 0800 and working outdoors until 1700 with their face, chest, back, legs, arms, and forearms exposed to sunlight" (Harinarayan et al., 2007). In a study from Saudi Arabia, levels below 25 nmol/L were found in respectively 35%, 45%, 53%, and 50% of normal male university students of Saudi, Jordanian, Egyptian, and other origins (Sedrani, 1984)."

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.

"One of the surprises over the past year has been all the research regarding Vitamin D and brain health. Give that many people are spending less time outdoors and more time in front of their computers, we all should be concerned, as Vitamin D comes in part from our exposure to the sun. Low Vitamin D levels have been associated with pain, depression, MS, cancer and now perhaps even dementia. Here are the results of a new study that should cause all of us to pay attention. I frequently check the Vitamin D levels in my patients and frrequently see that they are below the optimal level. Get your levels checked if you have any of these concerns. A new large-scale senior population study has found that a lack of vitamin D in the elderly could be linked to cognitive impairment. The study, conducted on almost 2,000 adults over the age of 65, is the first of its scale to identify this relationship, and prompted researchers to suggest vitamin D supplementation as a possible means of reducing the risk of dementia. "

"Study finds inadequate levels of Vitamin D may significantly increase risk of stroke, heart disease and death MURRAY, UT - While mothers have known that feeding their kids milk builds strong bones, a new study by researchers at the Heart Institute at Intermountain Medical Center in Salt Lake City suggests that Vitamin D contributes to a strong and healthy heart as well - and that inadequate levels of the vitamin may significantly increase a person's risk of stroke, heart disease, and death, even among people who've never had heart disease. For more than a year, the Intermountain Medical Center research team followed 27,686 patients who were 50 years of age or older with no prior history of cardiovascular disease. The participants had their blood Vitamin D levels tested during routine clinical care. The patients were divided into three groups based on their Vitamin D levels - normal (over 30 nanograms per milliliter), low (15-30 ng/ml), or very low (less than 15 ng/ml). The patients were then followed to see if they developed some form of heart disease."

"Study Shows Vitamin D Supplements May Be Useful in Preventing Heart Disease Nov. 16, 2009 (Orlando, Fla.) -- Some men with low levels of vitamin D in their blood are at particularly high risk of developing heart disease and weakened bones that can lead to osteoporosis, researchers report. In a study of more than 1,000 men, those with low levels of both vitamin D and the sex hormone estrogen were at significantly increased risk of having cardiovascular disease, says study head Erin Michos, MD, a cardiologist at Johns Hopkins. "They were also at dramatically increased risk of osteopenia," or bone loss that can lead to osteoporosis, she says. "Our results suggest that vitamin D supplements, which are already prescribed to treat osteoporosis, may also be useful in preventing heart disease," Michos tells WebMD. Men with low levels of vitamin D and testosterone, on the other hand, were not at heightened risk for heart disease or osteopenia."

Serum 25-Hydroxyvitamin D Levels Among US Children Aged 1 to 11 Years: Do Children Need More Vitamin D? Mansbach JM, Ginde AA, Camargo CA Jr. Pediatrics. 2009 Nov;124(5):1404-1410. PMID: 19951983 CONCLUSIONS: On the basis of a nationally representative sample of US children aged 1 to 11 years, millions of children may have suboptimal levels of 25(OH)D, especially non-Hispanic black and Hispanic children. More data in children are needed not only to understand better the health implications of specific serum levels of 25(OH)D but also to determine the appropriate vitamin D supplement requirements for children.

Vitamin D and diabetes: improvement of glycemic control with vitamin D3 repletion. Schwalfenberg G. Can Fam Physician. 2008 Jun;54(6):864-6. PMID: 18556494 Conclusion These cases support information that is already known about VTD and its effect on the islet cell. As discussed above, this might be true only for vitamin D3 and not vitamin D2, although vitamin D2 has been shown to improve bone health. Vitamin D insufficiency or deficiency is common, and repletion might improve glycemic control early in type 2 diabetes. Diabetes is one of the fastest growing chronic diseases worldwide. Vitamin D3 is inexpensive and readily available. Well-designed clinical studies are required to ascertain if improving 25(OH)D levels from an insufficiency or deficiency to sufficiency improves glycemic control in diabetes. These studies need to be properly designed: a randomized controlled trial with VTD deficiency or insufficiency identified in diabetic patients of various ethnic

Estimation and fortification of vitamin D3 in pasteurized process cheese. Upreti P, Mistry VV, Warthesen JJ. J Dairy Sci. 2002 Dec;85(12):3173-81. PMID: 12512590 The objective of this study was to develop methods for the estimation and fortification of vitamin D3 in pasteurized Process cheese. Vitamin D3 was estimated using alkaline saponification at 70°C for 30 min, followed by extraction with petroleum ether:diethyl ether (90:10 vol/vol) and HPLC. The retention time for vitamin D3 was approximately 9 min. A standard curve with a correlation coefficient of 0.972 was prepared for quantification of vitamin D3 in unknown samples. In the second phase of the study, pasteurized Process cheeses fortified with commercial water- or fat-dispersible forms of vitamin D3 at a level of 100 IU per serving (28 g) were manufactured. There was no loss of vitamin D3 during Process cheese manufacture, and the vitamin was uniformly distributed. No losses of the vitamin occurred during storage of the fortified cheeses over a 9-mo period at 21 to 29°C and 4 to 6°C. There was an approximately 25 to 30% loss of the vitamin when cheeses were heated for 5 min in an oven maintained at 232°C. Added vitamin D3 did not impart any off flavors to the Process cheeses as determined by sensory analysis. There were no differences between the water- and fat-dispersible forms of the vitamin in the parameters measured in fortified cheeses