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Serum 25(OH)-vitamin D concentration and risk of esophageal squamous dysplasia. Abnet CC, Chen W, Dawsey SM, Wei WQ, Roth MJ, Liu B, Lu N, Taylor PR, Qiao YL. Cancer Epidemiol Biomarkers Prev. 2007 Sep;16(9):1889-93. PMID: 17855710 doi: 10.1158/1055-9965.EPI-07-0461 Background: Squamous dysplasia is the precursor lesion for esophageal squamous cell carcinoma, and nutritional factors play an important role in the etiology of this cancer. Previous studies using a variety of measures for vitamin D exposure have reached different conclusions about the association between vitamin D and the risk of developing esophageal cancer. Conclusions: Higher serum 25(OH)D concentrations were associated with significantly increased risk of squamous dysplasia. No obvious source of measured or unmeasured confounding explains this finding. In conclusion, we found that a higher serum 25(OH)D concentration was associated with an increased risk of esophageal squamous dysplasia, the precursor lesion for ESCC. This finding concurs with our previous prospective study which found that higher vitamin D status was associated with increased risk of incident ESCC in this same population. These unexpected findings suggest that further studies of the association of vitamin D and digestive tract cancers are needed before the effect of vitamin D in different populations can be elucidated.

Serum vitamin D concentration and prostate cancer risk: a nested case-control study. Ahn J, Peters U, Albanes D, Purdue MP, Abnet CC, Chatterjee N, Horst RL, Hollis BW, Huang WY, Shikany JM, Hayes RB; Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Project Team. J Natl Cancer Inst. 2008 Jun 4;100(11):796-804. Epub 2008 May 27. PMID: 18505967 doi:10.1093/jnci/djn152 CONCLUSION: The findings of this large prospective study do not support the hypothesis that vitamin D is associated with decreased risk of prostate cancer; indeed, higher circulating 25(OH)D concentrations may be associated with increased risk of aggressive disease. In summary, results from this large prospective study of men who underwent standardized prostate cancer screening in the context of a screening trial do not support the hypothesis that higher serum vitamin D status is associated with decreased risk of prostate cancer. The study showed no association of vitamin D level with nonaggressive disease; however, it raises the possibility that higher vitamin D level may be associated with increased risks for aggressive disease, although a clear monotonic dose-response relationship was lacking. Along with recent reports of adverse associations for higher vitamin D status and risk of pancreatic (32) and esophageal (33,34) cancer, caution should be taken in recommending high doses of vitamin D or sunlight exposure to the general public for prostate cancer prevention. Future analyses are warranted to confirm these results and to further clarify the effects of vitamin D on aggressive prostate cancer.

"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)."

Vitamin D and prevention of breast cancer: pooled analysis. Garland CF, Gorham ED, Mohr SB, Grant WB, Giovannucci EL, Lipkin M, Newmark H, Holick MF, Garland FC. J Steroid Biochem Mol Biol. 2007 Mar;103(3-5):708-11. PMID: 17368188 CONCLUSIONS: Intake of 2000 IU/day of Vitamin D(3), and, when possible, very moderate exposure to sunlight, could raise serum 25(OH)D to 52 ng/ml, a level associated with reduction by 50% in incidence of breast cancer, according to observational studies.

"NEW YORK (Reuters Health) - Low vitamin D levels in the body may be deadly, according to a new study hinting that adults with lower, versus higher, blood levels of vitamin D may be more likely to die from heart disease or stroke. Vitamin D is an essential vitamin mostly obtained from direct sunlight exposure, but also found in foods and multivitamins. Dr. Annamari Kilkkinen, at the National Institute for Health and Welfare in Helsinki, Finland, and colleagues compared blood levels of vitamin D and deaths from heart disease or stroke over time in 2,817 men and 3,402 women in Finland."

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. "

"Posted Tue Nov 17, 2009 4:01pm AEDT Updated Tue Nov 17, 2009 4:27pm AEDT Researchers are advising people with MS to take safe levels of vitamin D supplements. Researchers are advising people with MS to take safe levels of vitamin D supplements. (ABC News: Giulio Saggin, file photo) * Audio: New research shows Vitamin D may slow the progress of MS (The World Today) Australian scientists have found that Vitamin D may slow the progression of multiple sclerosis (MS). Figures showing that people living in Tasmania are seven times more likely to develop MS than Queenslanders had suggested a link between sunlight exposure and the disease. "

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

"Researchers at Johns Hopkins are reporting what is believed to be the first conclusive evidence in men that the long-term ill effects of vitamin D deficiency are amplified by lower levels of the key sex hormone estrogen, but not testosterone. In a national study in 1010 men, to be presented Nov. 15 at the American Heart Association's (AHA) annual Scientific Sessions in Orlando, researchers say the new findings build on previous studies showing that deficiencies in vitamin D and low levels of estrogen, found naturally in differing amounts in men and women, were independent risk factors for hardened and narrowed arteries and weakened bones. Vitamin D is an essential part to keeping the body healthy, and can be obtained from fortified foods, such as milk and cereals, and by exposure to sunlight.

High-dose vitamin D3 supplementation in a cohort of breastfeeding mothers and their infants: a 6-month follow-up pilot study. Wagner CL, Hulsey TC, Fanning D, Ebeling M, Hollis BW. Breastfeed Med. 2006 Summer;1(2):59-70. PMID: 17661565 doi:10.1089/bfm.2006.1.59. Objective: To examine the effect of high-dose maternal vitamin D3 (vitD) supplementation on the nutritional vitD status of breastfeeding (BF) women and their infants compared with maternal and infant controls receiving 400 and 300 IU vitD/day, respectively. Design: Fully lactating women (n = 19) were enrolled at 1-month postpartum into a randomized- control pilot trial. Each mother received one of two treatments for a 6-month study period: 0 or 6000 IU vitD3 plus a prenatal vitamin containing 400 IU vitD3. The infants of mothers assigned to the control group received 300 IU vitD3/day; those infants of mothers in the high-dose group received 0 IU (placebo). Maternal serum and milk vitD and 25(OH)D were measured at baseline then monthly; infant serum vitD and 25(OH)D were measured at baseline, and months 4 and 7. Urinary calcium/creatinine ratios were measured monthly in both mothers and infants. Dietary and BF history and outdoor activity questionnaires were completed at each visit. Changes in skin pigmentation were measured by spectrophotometry. Data were analyzed using chi-square, t-test, and analysis of variance (ANOVA) on an intent-to-treat basis. Conclusion: With limited sun exposure, an intake of 400 IU/day vitamin D3 did not sustain circulating maternal 25(OH)D levels, and thus, supplied only extremely limited amounts of vitamin D to the nursing infant via breast milk. Infant levels achieved exclusively through maternal supplementation were equivalent to levels in infants who received oral vitamin D supplementation. Thus, a maternal intake of 6400 IU/day vitamin D elevated circulating 25(OH)D in both mother and nursing infant.

"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. "

"Numerous studies link Vitamin D and influenza, as well as Vitamin D and respiratory infections more generally. This vitamin up-regulates genetic expression of various endogenous antimicrobial peptides (AMP), which exhibit broad-spectrum microbicidal activity against bacteria, fungi, and viruses. Reports discussed below indicate that susceptibility to influenza is reduced with higher levels of sun exposure or vitamin D supplementation. Seasonal variation of vitamin D levels in humans can help explain the seasonality of flu epidemics."

"Hypovitaminosis D is a deficiency of Vitamin D. It can result from: inadequate intake coupled with inadequate sunlight exposure (in particular sunlight with adequate ultra violet B rays), disorders that limit its absorption, conditions that impair conversion of vitamin D into active metabolites, such as liver or kidney disorders, or, rarely, by a number of hereditary disorders.[1] Deficiency results in impaired bone mineralization, and leads to bone softening diseases, rickets in children and osteomalacia in adults, and contributes to osteoporosis.[1] Osteomalacia may also occur rarely as a side-effect of phenytoin use Hypovitaminosis D is typically diagnosed by measuring the concentration in blood of the compound 25-hydroxyvitamin D (calcidiol), which is a precursor to the active form 1,25-dihydroxyvitamin D (calcitriol).[6] One recent review has proposed the following four categories for hypovitaminosis D:[7] * Insufficient 50-100 nmol/L (20-40 ng/mL) * Mild 25-50 nmol/L (10-20 ng/mL) * Moderate 12.5-25.0 nmol/L (5-10 ng/mL) * Severe < 12.5 nmol/L (< 5 ng/mL) Note that 1.0 nmol/L = 0.4 ng/mL for this compound.[8] Other authors have suggested that a 25-hydroxyvitamin D level of 75-80 nmol/L (30-32 ng/mL) may be sufficient

Vitamin D deficiency: a worldwide problem with health consequences. Holick MF, Chen TC. Am J Clin Nutr. 2008 Apr;87(4):1080S-6S. Review. PMID: 18400738 A reevaluation needs to take place of what the adequate intakes of vitamin D should be for children and adults. The literature over the past decade suggests that the Institute of Medicine recommendations in 1997 (83) are inadequate, and some experts including us suggest that both children and adults should take ≥800-1000 IU vitamin D/d from dietary and supplemental sources (4, 9, 77) when sunlight is unable to provide it. This recommendation, however, has not yet been embraced either by official government or pediatric organizations in the United States, Canada, or Europe for either children or adults.

The association of solar ultraviolet B (UVB) with reducing risk of cancer: multifactorial ecologic analysis of geographic variation in age-adjusted cancer mortality rates. Grant WB, Garland CF. Anticancer Res. 2006 Jul-Aug;26(4A):2687-99. PMID: 16886679 CONCLUSION: These results provide additional support for the hypothesis that solar UVB, through photosynthesis of vitamin D, is inversely-associated with cancer mortality rates, and that various other cancer risk-modifying factors do not detract from this link. It is thought that sun avoidance practices after 1980, along with improved cancer treatment, led to reduced associations in the latter period. The results regarding solar UVB should be studied further with additional observational and intervention studies of vitamin D indices and cancer incidence, mortality and survival rates.

Vitamin D and multiple sclerosis. Hayes CE, Cantorna MT, DeLuca HF. Proc Soc Exp Biol Med. 1997 Oct;216(1):21-7. Review. PMID: 9316607

Vitamin D treatment in multiple sclerosis. Myhr KM. J Neurol Sci. 2009 Jun 22. [Epub ahead of print] PMID: 19549608 doi:10.1016/j.jns.2009.05.002 Epidemiological evidence combined with clinical and laboratory analyses, and experimental animal models, suggest a possible influence of vitamin D on MS susceptibility as well as clinical disease activity. Supplement with vitamin D may reduce the risk of developing MS. An intervention may also reduce the risk of conversion from a first clinical event suggestive of MS to clinical definite MS, as well as reduce the relapse rate among patients with relapsing remitting MS. More studies are, however, needed to determine optimal dose and serum level for vitamin D, as well as target populations and optimal timing for intervention.

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.