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Matti Narkia

sunlightD.org - Main -sunlightandvitamind.com - 1 views

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    sunlightD.org

    Grassroots Health and ZRT Labs are working together to help us all make sure we have enough vitamin D. Participate in understanding vitamin D. Visit grassrootshealth.net and join the research project. You'll get your D tested twice a year for five years. The cost is just $40 a test, $80 a year, more than reasonable for accurate D testing, and you'll help provide real answers, for yourself and for us all, about how much D we get and how much we need. Join now. Do commit to the full 5 years if you decide to sign on. If not joining for the full test period please use the testing links below.

Matti Narkia

Hyperlipid: Vitamin D and UV fluctuations (2) - 0 views

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    "I discussed in my last post how Dr Vieth has a model of tissue 1,25(OH)2D synthesis and degradation in which the level of active substance is pretty well independent of blood vitamin D level, provided the level is either rising or stable. I think it is also worth pointing out that he is talking, hypothetically, about tissue 1,25(OH)2D, not plasma level... As we know, almost nothing is known about tissue 1,25(OH)2D control.

    By Vieth's hypothesis tissue 1,25(OH)2D is OK so long as there is at least SOME vitamin D present in plasma and the level dose not vary too much. Obviously there is a level below which you can have as much of the enzyme for converting vitamin D to the active form as you like, if there is no vitamin D in your blood you can't make any 1,25(OH)2D in your tissues, or in your kidneys for export to your blood to control calcium levels. At the lower extremes we have rickets and osteomalacia. These are clear cut, unarguable markers of vitamin D deficiency, in the absence of confounding factors (there are a few)."
Matti Narkia

Seasonality of UV-radiation and vitamin D status at 69 degrees north. - Photochem Photo... - 1 views

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    Seasonality of UV-radiation and vitamin D status at 69 degrees north.
    Brustad M, Edvardsen K, Wilsgaard T, Engelsen O, Aksnes L, Lund E.
    Photochem Photobiol Sci. 2007 Aug;6(8):903-8. Epub 2007 Jun 27.
    PMID: 17668121

    The generally high dietary intakes of vitamin D, especially in winter, mask largely the effect of seasonal variation in UV-exposure, causing an atypical seasonal variation in vitamin D status. The UV-hour variable significantly predicted 25(OH)D levels in blood when adjusted for intakes and artificial UV-radiation exposure and sun holidays abroad.
Matti Narkia

The High Prevalence of Vitamin D Insufficiency across Australian Populations Is Only Pa... - 1 views

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    The high prevalence of vitamin D insufficiency across Australian populations is only partly explained by season and latitude.
    van der Mei IA, Ponsonby AL, Engelsen O, Pasco JA, McGrath JJ, Eyles DW, Blizzard L, Dwyer T, Lucas R, Jones G.
    Environ Health Perspect. 2007 Aug;115(8):1132-9.
    PMID: 17687438
    doi: 10.1289/ehp.9937.

    Conclusion
    Vitamin D insufficiency is common over a wide latitude range in Australia. Season appears to be more important than latitude, but both accounted for less than one-fifth of the variation in serum 25(OH)D levels, highlighting the importance of behavioral factors. Current sun exposure guidelines do not seem to fully prevent vitamin D insufficiency, and consideration should be given to their modification or to pursuing other means to achieve vitamin D adequacy.
Matti Narkia

Ultraviolet exposure scenarios: risks of erythema from recommendations on cutaneous vit... - 0 views

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    Ultraviolet exposure scenarios: risks of erythema from recommendations on cutaneous vitamin D synthesis.
    Webb AR, Engelsen O.
    Adv Exp Med Biol. 2008;624:72-85.
    PMID: 18348448
    DOI: 10.1007/978-0-387-77574-6_6
Matti Narkia

VitD-ez Easy Duration of Vitamin D Synthesis in Human Skin - 0 views

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    Vitamin D production in human skin occurs only when UV radiation exceeds a threshold. From simulations of UV irradiances, the VitD-ez www page ( http://zardoz.nilu.no/~olaeng/fastrt/VitD-ez.html) computes the daily duration of dermal vitamin D production at midday when UV radiation exceeds the required threshold. The VitD-ez www page is a simplified version of the more complex VitD web page ( http://zardoz.nilu.no/~olaeng/fastrt/VitD.html). The simplified VitD-ez www page is convenient for users unfamiliar to radiative transfer modelling, because the model input is limited and more intuitive.
Matti Narkia

Daily duration of vitamin D synthesis in human skin with relation to latitude, total oz... - 1 views

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    Daily duration of vitamin D synthesis in human skin with relation to latitude, total ozone, altitude, ground cover, aerosols and cloud thickness.
    Engelsen O, Brustad M, Aksnes L, Lund E.
    Photochem Photobiol. 2005 Nov-Dec;81(6):1287-90.
    PMID: 16354110

    Vitamin D production in human skin occurs only when incident UV radiation exceeds a certain threshold. From simulations of UV irradiances worldwide and throughout the year, we have studied the dependency of the extent and duration of cutaneous vitamin D production in terms of latitude, time, total ozone, clouds, aerosols, surface reflectivity and altitude. For clear atmospheric conditions, no cutaneous vitamin D production occurs at 51 degrees latitude and higher during some periods of the year. At 70 degrees latitude, vitamin D synthesis can be absent for 5 months. Clouds, aerosols and thick ozone events reduce the duration of vitamin D synthesis considerably, and can suppress vitamin D synthesis completely even at the equator. A web page allowing the computation of the duration of cutaneous vitamin D production worldwide throughout the year, for various atmospheric and surface conditions, is available on the Internet at http://zardoz.nilu.no/~olaeng/fastrt/VitD.html and http://zardoz.nilu.no/~olaeng/fastrt/VitD-ez.html. The computational methodology is outlined here.
Matti Narkia

Vitamin D deficiency is the cause of common obesity - 0 views

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    Vitamin D deficiency is the cause of common obesity.
    Foss YJ.
    Med Hypotheses. 2009 Mar;72(3):314-21. Epub 2008 Dec 2.
    PMID: 19054627
    doi:10.1016/j.mehy.2008.10.005

    Common obesity and the metabolic syndrome may therefore result from an anomalous adaptive winter response. The stimulus for the winter response is proposed to be a fall in vitamin D. The synthesis of vitamin D is dependent upon the absorption of radiation in the ultraviolet-B range of sunlight. At ground level at mid-latitudes, UV-B radiation falls in the autumn and becomes negligible in winter. It has previously been proposed that vitamin D evolved in primitive organisms as a UV-B sensitive photoreceptor with the function of signaling changes in sunlight intensity. It is here proposed that a fall in vitamin D in the form of circulating calcidiol is the stimulus for the winter response, which consists of an accumulation of fat mass (obesity) and the induction of a winter metabolism (the metabolic syndrome). Vitamin D deficiency can account for the secular trends in the prevalence of obesity and for individual differences in its onset and severity. It may be possible to reverse the increasing prevalence of obesity by improving vitamin D status.
Matti Narkia

Vitamin D and influenza - Wikipedia, the free encyclopedia - 0 views

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    "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."
Matti Narkia

Plasma calcidiol, season, and serum parathyroid hormone concentrations in healthy elder... - 0 views

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    Plasma calcidiol, season, and serum parathyroid hormone concentrations in healthy elderly men and women.
    Dawson-Hughes B, Harris SS, Dallal GE.
    Am J Clin Nutr. 1997 Jan;65(1):67-71.
    PMID: 8988915

    Plasma calcidiol and serum PTH concentrations were inversely related, with PTH rising slowly as calcidiol concentrations declined below 110 nmol/L (95 CI: 60, 168 nmol/L). More than 90% of the men and women had calcidiol concentrations below this value in the wintertime. The high prevalence of lower wintertime calcidiol values may increase risk of bone loss in elderly men and women.
Matti Narkia

Vitamin D Deficiency and Seasonal Variation in an Adult South Florida Population -- Lev... - 0 views

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    Vitamin d deficiency and seasonal variation in an adult South Florida population.
    Levis S, Gomez A, Jimenez C, Veras L, Ma F, Lai S, Hollis B, Roos BA.
    J Clin Endocrinol Metab. 2005 Mar;90(3):1557-62. Epub 2005 Jan 5.
    PMID: 15634725

    The prevalence of hypovitaminosis D is considerable even in southern latitudes and should be taken into account in the evaluation of postmenopausal and male osteoporosis.
Matti Narkia

Are sunlight deprivation and influenza epidemics associated with the onset of acute leu... - 0 views

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    Are sunlight deprivation and influenza epidemics associated with the onset of acute leukemia?
    Timonen T, Näyhä S, Koskela T, Pukkala E.
    Haematologica. 2007 Nov;92(11):1553-6.
    PMID: 18024404
    doi:10.3324/haematol.10799

    Month of diagnosis of 7,423 cases of acute leukemia (AL) in Finland during 1964-2003 were linked with data on influenza and solar radiation. Acute myeloblastic leukemia (AML) showed the highest risk in the dark season. During the light season, the incidence decreased by 58% (95% confidence interval, 16-79%) per 1,000 kJ/m2/d increase of solar radiation. Independent of solar radiation, AML increased by 9% (95% confidence interval, 0-19%) during influenza epidemics. Reoccurring at the same time annually, darkness-related vitamin D deficiency and influenza could cause successive and co-operative mutations leading to AL with a short latency.
Matti Narkia

Vitamin D and living in northern latitudes--an endemic risk area for vitamin D deficien... - 0 views

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    Vitamin D and living in northern latitudes--an endemic risk area for vitamin D deficiency.
    Huotari A, Herzig KH.
    Int J Circumpolar Health. 2008 Jun;67(2-3):164-78. Review.
    PMID: 18767337

    CONCLUSIONS: Vitamin D plays a fundamental role in calcium and phosphate homeostasis. A deficiency of vitamin D has been attributed to several diseases. Since its production in the skin depends on exposure to UVB-radiation via the sunlight, the level of vitamin D is of crucial importance for the health of inhabitants who live in the Nordic latitudes where there is diminished exposure to sunlight during the winter season. Therefore, fortification or supplementation of vitamin D is necessary for most of the people living in the northern latitudes during the winter season to maintain adequate levels of circulating 25(OH)D3 to maintain optimal body function and prevent diseases.
Matti Narkia

Association between serum 25-hydroxyvitamin D and depressive symptoms in Japanese: anal... - 0 views

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    Association between serum 25-hydroxyvitamin D and depressive symptoms in Japanese: analysis by survey season
    A Nanri, T Mizoue, Y Matsushita, K Poudel-Tandukar, M Sato, M Ohta, N Mishima
    European Journal of Clinical Nutrition (19 August 2009) doi:10.1038/ejcn.2009.96 Short Communication
Matti Narkia

Vitamin D Is Associated with Improved Survival in Early-Stage Non-Small Cell Lung Cance... - 0 views

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    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.
Matti Narkia

In vivo threshold for cutaneous synthesis of vitamin D3. - [J Lab Clin Med. 1989] - Pub... - 0 views

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    In vivo threshold for cutaneous synthesis of vitamin D3.
    Matsuoka LY, Wortsman J, Haddad JG, Hollis BW.
    J Lab Clin Med. 1989 Sep;114(3):301-5.
    PMID: 2549141
Matti Narkia

An evaluation of the relative contributions of exposure to sunlight and of diet to the ... - 0 views

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    An evaluation of the relative contributions of exposure to sunlight and of diet to the circulating concentrations of 25-hydroxyvitamin D in an elderly nursing home population in Boston.
    Webb AR, Pilbeam C, Hanafin N, Holick MF.
    Am J Clin Nutr. 1990 Jun;51(6):1075-81.
    PMID: 2349922
Matti Narkia

Season of diagnosis is a prognostic factor in Hodgkin's lymphoma: a possible role of su... - 0 views

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    SSeason of diagnosis is a prognostic factor in Hodgkin's lymphoma: a possible role of sun-induced vitamin D.
    Porojnicu AC, Robsahm TE, Ree AH, Moan J.
    Br J Cancer. 2005 Sep 5;93(5):571-4.
    PMID: 16136030
    doi:10.1038/sj.bjc.6602722

    Epidemiological data for this period indicate that season of diagnosis is a strong prognostic factor for Hodgkin's lymphoma, with approximately 20% lower case fatality for patients diagnosed during autumn vs winter diagnosis (RR = 0.783, 95% CI,-0.62 to 0.99; P = 0.041). Notably, the improved autumnal survival rate was higher than 60% (RR = 0.364, 95% CI, -0.15 to 0.87; P = 0.025) for patients younger than 30 years. This finding may be related to higher endogenous levels of vitamin D in autumn, with a favourable influence on the conventional therapy.

    In conclusion, we have found that the prognosis of Hodgkin's lymphoma is significantly correlated with the season of diagnosis, particularly for patients younger than 30 years. This seasonal effect is presumably due to the vitamin D3 synthesis in skin during sun exposure. The present findings should encourage further investigations of the possible adjuvant role of vitamin D derivatives in cancer therapy
Matti Narkia

Vitamin D Is Associated with Improved Survival in Early-Stage Non-Small Cell Lung Cance... - 0 views

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    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.
Matti Narkia

Rise in prostate-specific antigen in men with untreated low-grade prostate cancer is sl... - 0 views

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    Rise in prostate-specific antigen in men with untreated low-grade prostate cancer is slower during spring-summer.
    Vieth R, Choo R, Deboer L, Danjoux C, Morton GC, Klotz L.
    Am J Ther. 2006 Sep-Oct;13(5):394-9.
    PMID: 16988533
    doi: 10.1097/01.mjt.0000174346.36307.02
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