Posted: Mon 12 Jul 2010 14:36
Scientists Demonstrate Antifungal Properties Of Vitamin B3 :
LymeNet Europe Forum
Photodermatol Photoimmunol Photomed. 2010 Aug;26(4):172-6.
Is casual exposure to summer sunlight effective at maintaining adequate vitamin D status?
Department of Dermatological Sciences, Institute of Cellular Medicine, University of Newcastle, Newcastle Upon Tyne, UK. firstname.lastname@example.org
BACKGROUND/PURPOSE: The advice that an adequate vitamin D status can be achieved by short, casual exposure to summer sunlight is ubiquitous. This review will examine the value of this advice.
METHODS: The results of experimental studies on changes in serum 25-hydroxyvitamin D [25(OH)D] concentrations following ultraviolet exposure are interpreted in the context of human exposure to sunlight.
RESULTS: It is shown that current advice about modest sun exposure during the summer months does little in the way of boosting overall 25(OH)D levels, while sufficient sun exposure that could achieve a worthwhile benefit would compromise skin health.
CONCLUSIONS: Failure to understand the nature of human exposure to sunlight has led to misguided advice concerning the sun exposure necessary for an adequate vitamin D status.
Acta Neurol Scand Suppl. 2010;(190):88-92.
Assessing vitamin D in the central nervous system.
Holmøy T, Moen SM.
Department of Neurology, Oslo University Hospital Ullevål, Oslo, Norway. email@example.com
Epidemiological and experimental evidence suggest that vitamin D deficiency is a risk factor for multiple sclerosis and other autoimmune diseases. The activated form of vitamin D exerts several immunomodulating properties in vitro and in vivo, that could contribute to explain the association with multiple sclerosis. Hypovitaminosis D is also associated with several other neurological diseases that is less likely mediated by dysregulated immune responses, including Parkinson's disease and Alzheimer's disease, schizophrenia and affective disorders, suggesting a more diverse role for vitamin D in the maintenance of brain health. Accordingly, both the vitamin D receptor and the enzymes necessary to synthesize bioactive 1,25-dihydroxyvitamin D are expressed in the brain, and hypovitaminosis D is associated with abnormal development and function of the brain. We here review current knowledge on the intrathecal vitamin D homeostasis in heath and disease, highlighting the need to assess vitamin D in the intrathecal compartment.
South Med J. 2010 Jul 8. [Epub ahead of print]
Effects of Vitamin D Supplementation on Blood Pressure.
Wu SH, Ho SC, Zhong L.
From the School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong SAR, People's Republic of China, and Nanjing Maternal and Child Health Care Hospital, Nanjing City, People's Republic of China; School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong SAR, People's Republic of China; and School of Basic Medical Science, Southeast University, People's Republic of China, and Department of Orthopaedics and Traumatology, Musculoskeletal Research Laboratory, The Chinese University of Hong Kong, Hong Kong SAR, People's Republic of China.
OBJECTIVE:: Inconsistent findings from epidemiological studies have continued the controversy over the role of oral vitamin D supplementation in reducing blood pressure in normotensive or hypertensive populations.
METHODS:: We performed a literature search up to December 2009, with no restrictions. Only double-blind randomized controlled trials (RCTs) of oral vitamin D supplementation in normotensive or hypertensive individuals with blood pressure measurements were included.
RESULTS:: From 244 retrieved papers, four RCTs involving 429 participants met our inclusion criteria for this meta-analysis. Vitamin D supplementation reduced systolic blood pressure (SBP) by 2.44 mm Hg (weighted mean difference [WMD]: -2.44, 95% confidence interval [CI]: -4.86, -0.02), but not diastolic blood pressure (DBP) (WMD: -0.02, 95% CI: -4.04, 4.01) compared with calcium or placebo. Subgroup analysis suggested that the change of blood pressure did not vary markedly across the dose of vitamin D supplementation, study length, or intervention.
CONCLUSIONS:: Oral vitamin D supplementation may lead to a reduction in systolic blood pressure but not diastolic blood pressure. Given the small number of trials and small but statistically significant reduction in systolic blood pressure from this meta-analysis, further studies are required to confirm the magnitude of the effect of vitamin D on blood pressure reduction and define the optimum dose, dosing interval, and type of vitamin D to administer.
Exp Biol Med (Maywood). 2010 Jul 28. [Epub ahead of print]
Vitamin D nutritional policy needs a vision for the future.
Norman AW, Bouillon R.
Department of Biochemistry and Division of Biomedical Sciences, University of California, Riverside, CA 92521, USA.
Historically vitamin D is known to be essential for normal bone growth and quality, and thus appropriate dietary vitamin D supplementation can eliminate vitamin D deficiency childhood rickets and adult osteomalacia. In spite of many government and medical associations' worldwide guidelines for the reference daily intake (RDI) of vitamin D, scientists and nutritionists from many countries agree that at present about half of elderly North Americans and Western Europeans and probably also of the rest of the world are not receiving enough vitamin D to maintain healthy bone. In addition, over the past decade there has been a dramatic increase in our understanding of the many biological actions that result from vitamin D acting through its daughter steroid hormone, 1alpha,25-dihydroxyvitamin D(3) [1alpha,25(OH)(2)D(3)] in collaboration with its cognate vitamin D receptor (VDR). Consequently, evidence has accumulated that beside intestine and bone, there are five additional physiological systems where the VDR with 1alpha,25(OH)(2)D generates biological responses. These include the immune system (both the innate and adaptive), pancreas and metabolic homeostasis, heart-cardiovascular, muscle and brain systems as well as the control of the cell cycle, and thus of the disease process of cancer. Acting through the VDR, 1alpha,25(OH)(2)D(3) can produce a wide array of favorable biological effects that collectively are projected to contribute to the improvement of human health. Responsible medicine demands that worldwide vitamin D nutritional guidelines reflect current scientific knowledge about vitamin D's spectrum of activities. Thus, worldwide vitamin D nutritional policy is now at a crossroads. This paper presents several proposed policy changes with regard to the amount of vitamin D daily intake that if implemented will maximize vitamin D's contribution to reducing the frequency of many diseases, which would then increase the quality and longevity of life and significantly reduce the cost of medical care worldwide.