Health Now

Vitamin D production in human skin occurs only when UV radiation exceeds a threshold. From simulations of UV irradiances, the VitD www page ( http://zardoz.nilu.no/~olaeng/fastrt/VitD.html) computes the daily duration of dermal vitamin D production at midday when UV radiation exceeds the required threshold. The daily duration depends on latitude, time, total ozone, clouds, aerosols, surface reflectivity and altitude all of which can be specified by the user

Review: vitamin D, immunity and lupus. Cutolo M, Otsa K. Lupus. 2008;17(1):6-10. Review. PMID: 18089676 DOI: 10.1177/0961203307085879

Clinical aspects of vitamin D in the management of rheumatoid arthritis.\nLeventis P, Patel S.\nRheumatology (Oxford). 2008 Nov;47(11):1617-21. Epub 2008 Aug 5. Review.\nPMID: 18682414 \ndoi:10.1093/rheumatology/ken296 \n

itamin D and autoimmunity: new aetiological and therapeutic considerations. Arnson Y, Amital H, Shoenfeld Y. Ann Rheum Dis. 2007 Sep;66(9):1137-42. Epub 2007 Jun 8. Review. PMID: 17557889 doi:10.1136/ard.2007.069831

An association of serum vitamin D concentrations < 40 nmol/L with acute respiratory tract infection in young Finnish men. Laaksi I, Ruohola JP, Tuohimaa P, Auvinen A, Haataja R, Pihlajamäki H, Ylikomi T. Am J Clin Nutr. 2007 Sep;86(3):714-7. PMID: 17823437

Low vitamin d levels predict stroke in patients referred to coronary angiography.\nPilz S, Dobnig H, Fischer JE, Wellnitz B, Seelhorst U, Boehm BO, März W.\nStroke. 2008 Sep;39(9):2611-3. Epub 2008 Jul 17.\nPMID: 18635847 \ndoi: 10.1161/STROKEAHA.107.513655

Bischoff-Ferrari HA, Giovannucci E, Willett WC, Dietrich T, Dawson-Hughes B. Estimation of optimal serum concentrations of 25-hydroxyvitamin D for multiple health outcomes. Am J Clin Nutr. 2006 Jul;84(1):18-28. Review. PMID: 16825677

On the epidemiology of influenza. Cannell JJ, Zasloff M, Garland CF, Scragg R, Giovannucci E. Virol J. 2008 Feb 25;5:29. Review. PMID: 18298852 doi:10.1186/1743-422X-5-29

In the July 2005 FASEB Journal, Adrian F. Gombart of the University of California, Los Angeles (UCLA) and his colleagues reported that vitamin D boosts production in white blood cells of one of the antimicrobial compounds that defends the body against germs.\n\nImmediately, Cannell says, the proverbial lightbulb went on in his head: Maybe the high doses of vitamin D that he had been prescribing to virtually all the men on his ward had boosted their natural arsenal of the antimicrobial, called cathelicidin, and protected them from flu. Cannell had been administering the vitamin D because his patients, like many other people in the industrial world, had shown a deficiency:

EPIDEMICS' TIMING DETERMINED BY LATITUDEGoing back to 1945, Hope-Simpson discovered that influenza epidemics above 30 degrees latitude in both hemispheres occurred during the six months of least solar radiation and that outbreaks in the tropics almost always occured during the rainy season. He thus concluded, "Latitude alone broadly determines the timing of the epidemics in the annual cycle, a relationship that suggests a rather direct effect of some component of solar radiation acting positively or negatively upon the virus, the human host, or their interaction." That is, something may be regularly reducing our immunity every fall and winter. In 2003 researchers confirmed that influenza epidemics in the tropics occur, with few exceptions, during the rainy season, when vitamin D levels should be falling

Cannell JJ, Vieth R, Umhau JC, Holick MF, Grant WB, Madronich S, Garland CF, Giovannucci E. Epidemic influenza and vitamin D.Epidemiol Infect. 2006 Dec;134(6):1129-40. Epub 2006 Sep 7.PMID: 16959053 doi:10.1017/S0950268806007175

Association Between Serum 25-Hydroxyvitamin D Level and Upper Respiratory Tract Infection. \nAdit A. Ginde, MD, MPH; Jonathan M. Mansbach, MD; Carlos A. Camargo Jr, MD, DrPH . \nArch Intern Med. 2009;169(4):384-390\n

Is sunshine more than just a home remedy for a cold? New research suggests it may be: In a study that will be published tomorrow, people with low levels of vitamin D - also known as the "sunshine vitamin" - were more likely to catch cold and flu than folks with adequate amounts. The effect of the vitamin was strongest in people with asthma and other lung diseases who are predisposed to respiratory infections.