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Matti Narkia

Maternal vitamin D status during pregnancy and childhood bone mass at age 9 years: a lo... - 0 views

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    Maternal vitamin D status during pregnancy and childhood bone mass at age 9 years: a longitudinal study.
    Javaid MK, Crozier SR, Harvey NC, Gale CR, Dennison EM, Boucher BJ, Arden NK, Godfrey KM, Cooper C; Princess Anne Hospital Study Group.
    Lancet. 2006 Jan 7;367(9504):36-43. Erratum in: Lancet. 2006 May 6;367(9521):1486.
    PMID: 16399151
    doi:10.1016/S0140-6736(06)67922-1

    Interpretation
    Maternal vitamin D insufficiency is common during pregnancy and is associated with reduced bone-mineral accrual in the offspring during childhood; this association is mediated partly through the concentration of umbilical venous calcium. Vitamin D supplementation of pregnant women, especially during winter months, could lead to longlasting reductions in the risk of osteoporotic fracture in their offspring.
Matti Narkia

Ecological studies of ultraviolet B, vitamin D and cancer since 2000. - Ann Epidemiol. ... - 1 views

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    Ecological studies of ultraviolet B, vitamin D and cancer since 2000.
    Grant WB, Mohr SB.
    Ann Epidemiol. 2009 Jul;19(7):446-54. Epub 2009 Mar 9. Review.
    PMID: 19269856

    CONCLUSION: These findings provide strong evidence that vitamin D status plays an important role in controlling the outcome of cancer. Support for the UVB-vitamin D-cancer theory is now scientifically strong enough to warrant use of vitamin D in cancer prevention, and as a component of treatment. More research studies would help to explore whether there are benefits beyond the substantial effects that have been observed.
Matti Narkia

Daily duration of vitamin D synthesis in human skin with relation to latitude, total oz... - 0 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."
Matti Narkia

Decreased bioavailability of vitamin D in obesity -- Wortsman et al. 72 (3): 690 -- Ame... - 0 views

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    Decreased bioavailability of vitamin D in obesity.
    Wortsman J, Matsuoka LY, Chen TC, Lu Z, Holick MF.
    Am J Clin Nutr. 2000 Sep;72(3):690-3. Erratum in: Am J Clin Nutr. 2003 May;77(5):1342.
    PMID: 10966885

    Conclusions: Obesity-associated vitamin D insufficiency is likely due to the decreased bioavailability of vitamin D3 from cutaneous and dietary sources because of its deposition in body fat compartments.
Matti Narkia

Relationship between low ultraviolet B irradiance and higher breast cancer risk in 107 ... - 0 views

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    Relationship between low ultraviolet B irradiance and higher breast cancer risk in 107 countries.
    Mohr SB, Garland CF, Gorham ED, Grant WB, Garland FC.
    Breast J. 2008 May-Jun;14(3):255-60. Epub 2008 Apr 17.
    PMID: 18422861
    DOI: 10.1111/j.1524-4741.2008.00571.x

    There was a protective effect of UVB irradiance on risk of breast cancer that was independent of fertility rate, proportion of the population overweight, alcohol intake, animal energy intake, and other covariates.
Matti Narkia

Explaining multiple sclerosis prevalence by ultraviolet exposure: a geospatial analysis... - 0 views

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    Explaining multiple sclerosis prevalence by ultraviolet exposure: a geospatial analysis.
    Beretich B, Beretich T.
    Mult Scler. 2009 Aug;15(8):891-8.
    PMID: 19667017
    DOI: 10.1177/1352458509105579

    Conclusion

    This analysis suggests a strong association between UV radiation and MS distribution, and an increase in risk for MS in those areas with a low UVI.
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

Chronic Sunscreen Use Decreases Circulating Concentrations of 25-Hydroxyvitamin D: A Pr... - 0 views

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    Matsuoka, L. Y., Wortsman, J., Hanifan, N. & Holick, M. F. (1988)
    Chronic sunscreen use decreases circulating concentrations of 25-hydroxyvitamin D: a preliminary study.
    Arch. Dermatol. 124:1802-1804
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

Regulation of cutaneous previtamin D3 photosynthesis in man: skin pigment is not an ess... - 0 views

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    Holick, M. F., MacLaughlin, J. A. & Doppelt, S. H. (1981)
    Factors that influence the cutaneous photosynthesis of previtamin D3. Science 211:590-593

    When human skin was exposed to simulated solar ultraviolet radiation, epidermal 7-dehydrocholesterol was converted to previtamin D3. During prolonged exposure to simulated solar ultraviolet radiation, the synthesis of previtamin D3 reached a plateau at about 10 to 15 percent of the original 7-dehydrocholesterol content, and previtamin D3 was photoisomerized to two biologically inert isomers, lumisterol3 and tachysterol3. Increases either in skin melanin concentration or in latitude necessitated increases in the exposure time to simulated solar ultraviolet radiation required to maximize the formation, but not the total content, of previtamin D3. In order of importance, the significant determinants limiting the cutaneous production of previtamin D3 are (i) photochemical regulation, (ii) pigmentation, and (iii) latitude.
Matti Narkia

Geographic variation in breast cancer mortality in the United States: A hypothesis invo... - 0 views

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    Geographic variation in breast cancer mortality in the United States: a hypothesis involving exposure to solar radiation.
    Garland FC, Garland CF, Gorham ED, Young JF.
    Prev Med. 1990 Nov;19(6):614-22.
    PMID: 2263572
    doi:10.1016/0091-7435(90)90058-R

    Vitamin D from sunlight exposure may be associated with low risk for fatal breast cancer, and differences in ultraviolet light reaching the United States population may account for the striking regional differences in breast cancer mortality. The ecological nature of this study is emphasized, and the possibility that an indirect association with dietary and socioeconomic factors could explain these findings is discussed.
Matti Narkia

An ecologic study of dietary and solar ultraviolet-B links to breast carcinoma mortalit... - 0 views

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    An ecologic study of dietary and solar ultraviolet-B links to breast carcinoma mortality rates.
    Grant WB.
    Cancer. 2002 Jan 1;94(1):272-81.
    PMID: 11815987

    CONCLUSIONS
    It is hypothesized that animal products are associated with risk for breast carcinoma because they are associated with greater amounts of insulin-like growth factor-1and lifetime doses of estrogen. Vegetable products contain several risk reduction components including antioxidants and phytoestrogens. The association with latitude is very likely because of solar UV-B radiation and vitamin D. Alcohol modulates estrogen's effects on breasts. Fish intake is associated with risk reduction through vitamin D and n-3 oils. These results are consistent with those of many case-control and cohort studies but should be assessed in well designed cohort studies.
Matti Narkia

Geographic variation of prostate cancer mortality rates in the United States: Implicati... - 0 views

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    Geographic variation of prostate cancer mortality rates in the United States: Implications for prostate cancer risk related to vitamin D.
    Grant WB.
    Int J Cancer. 2004 Sep 1;111(3):470-1; author reply 472. No abstract available.
    PMID: 15221981
    10.1002/ijc.20220

    The implications of our results and those of Tuohimaa et al.[1] include the following. Vitamin D supplementation should be undertaken in wintertime, a period when it is impossible to produce vitamin D by solar UVB exposure in northeastern states.[13] Given these new results, the optimal vitamin D intake and production and serum 25(OH)-vitamin D3 levels for prostate cancer appear to be lower than for other cancers. However, when developing guidelines for vitamin D fortification, many factors should be included in the analysis, including all of the potential health benefits and possible risks of vitamin D, as well as age, sex, residence, child-bearing status, etc.[14] Also, the suggestion that daily vitamin D3 supplement doses of 100 g (4,000 IU)/day are safe[15] should be reexamined. Finally, in terms of preventing prostate cancer, more attention should be given to diet, which has the greatest environmental impact on risk of prostate cancer, with animal products being important risk factors and vegetable products, especially onions and other allium family members, being important risk-reduction factors.[16]
Matti Narkia

Vitamin D deficiency: a worldwide problem with health consequences -- Holick and Chen 8... - 0 views

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    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.
Matti Narkia

Factors that Influence the Cutaneous Synthesis and Dietary Sources of Vitamin D - 0 views

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    Factors that influence the cutaneous synthesis and dietary sources of vitamin D.
    Chen TC, Chimeh F, Lu Z, Mathieu J, Person KS, Zhang A, Kohn N, Martinello S, Berkowitz R, Holick MF.
    Arch Biochem Biophys. 2007 Apr 15;460(2):213-7. Epub 2007 Jan 8.
    PMID: 17254541
    doi: 10.1016/j.abb.2006.12.017

    Vitamin D is rare in food. Among the vitamin D-rich food, oily fish are considered to be one of the best sources. Therefore, we analyzed the vitamin D content in several commonly consumed oily and non-oily fish. The data showed that farmed salmon had a mean content of vitamin D that was ~25% of the mean content found in wild caught salmon from Alaska, and that vitamin D2 was found in farmed salmon, but not in wild caught salmon. The results provide useful global guidelines for obtaining sufficient vitamin D3 by cutaneous synthesis and from dietary intake to prevent vitamin D deficiency and its health consequences.ensuing illness, especially, bone fractures in the elderly.
Matti Narkia

Vitamin D and skin physiology: a D-lightful story - JBMR Online - Journal of Bone and M... - 0 views

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    Vitamin D and skin physiology: a D-lightful story.
    Holick MF, Chen TC, Lu Z, Sauter E.
    J Bone Miner Res. 2007 Dec;22 Suppl 2:V28-33.
    PMID: 18290718
    doi: 10.1359/jbmr.07s211

    Very few foods naturally contain vitamin D, and those that do have a very variable vitamin D content. Recently it was observed that wild caught salmon had between 75% and 90% more vitamin D(3) compared with farmed salmon. The associations regarding increased risk of common deadly cancers, autoimmune diseases, infectious diseases, and cardiovascular disease with living at higher latitudes and being prone to vitamin D deficiency should alert all health care professionals about the importance of vitamin D for overall health and well being.

    Humans have depended on sunlight for their vitamin D requirement. The impact of season, time of day, and latitude on vitamin D synthesis is well documented.(2,3) We now report that altitude also has a dramatic influence on vitamin D3 production and that living at altitudes above 3500 m permits previtamin D3 production at a time when very little is produced at latitudes below 3400 m. It was surprising that, at 27° N in Agra (169 M), little previtamin D3 production was observed. However, there was significant air pollution that caused a haze over the city. It is likely the ozone and other UVB-absorbing pollutants in the air prevented the solar UVB photons from reaching the earth's surface to produce previtamin D3.
Matti Narkia

Sunlight and Vitamin D: both good for cardiovascular health. - 0 views

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    Sunlight and vitamin D: both good for cardiovascular health.
    Holick MF.
    J Gen Intern Med. 2002 Sep;17(9):733-5.
    PMID: 12220371
    doi: 10.1046/j.1525-1497.2002.20731.x.
Matti Narkia

Circulating Vitamin D3 and 25-hydroxyvitamin D in Humans: An Important Tool to Define A... - 0 views

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    Circulating vitamin D3 and 25-hydroxyvitamin D in humans: An important tool to define adequate nutritional vitamin D status.
    Hollis BW, Wagner CL, Drezner MK, Binkley NC.
    J Steroid Biochem Mol Biol. 2007 Mar;103(3-5):631-4. Epub 2007 Jan 10.
    PMID: 17218096

    In the present study, we sought to investigate what circulating 25(OH)D levels would result in populations exhibiting no substrate limitations to the vitamin D-25-hydroxylase. To perform this, we chose two distinct populations. The first were individuals from a year-found sunny environment who spent a good deal of time outdoors. The second were a group of lactating women receiving a substantial daily oral dose of vitamin D3. Surprisingly, a study such as this previously had not been undertaken. There are several reasons for this. First, finding a group of sun-exposed individuals is not an easy task; in fact, we had to go to Hawaii to find them. Secondly, very few studies have been performed where subjects actually received adequate vitamin D3 supplementation to make them replete. Finally, it is very difficult and costly to measure circulating vitamin D3 and relate it to circulating 25(OH)D. The results of our study are far-reaching.

    This study also demonstrates that individuals can be vitamin D deficient with significant sun exposure if the skin area exposed is limited as was suggested several years ago (19). Finally, whether one receives their vitamin D3 orally or through UV exposure, the vitamin D-25-hydroxylase appears to handle it in an equivalent fashion with respect to maintaining circulating 25(OH)D levels. Thus, we believe that the relationship between circulating vitamin D and 25(OH)D may define adequate nutritional vitamin D status.
Matti Narkia

Vitamin D: a D-Lightful health perspective. - Nutr Rev. 2008 Oct;66(10 Suppl 2):S182-94... - 0 views

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    Vitamin D: a D-Lightful health perspective.
    Holick MF.
    Nutr Rev. 2008 Oct;66(10 Suppl 2):S182-94. Review.
    PMID: 18844847
    DOI: 10.1111/j.1753-4887.2008.00104.x

    Sunlight provides most humans with their vitamin D requirement. Adequate vitamin D(3) by synthesis in the skin or from dietary and supplemental sources is essential for bone health throughout life. Vitamin D deficiency is defined as a 25(OH)D concentration <20 ng />30 ng/mL (75 nmol/L), and insufficiency as 21-29 ng/mL. Vitamin D deficiency and insufficiency has been linked to a wide variety of chronic diseases including common cancers, autoimmune, cardiovascular, and infectious diseases. Healthcare professionals need to be aware of the vitamin D deficiency pandemic. Guidelines for sensible sun exposure and supplemental vitamin D of 800-1000 IU/day are needed.
Matti Narkia

Current Impediments to Acceptance of the Ultraviolet-B-Vitamin D-Cancer Hypothesis - An... - 0 views

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    Current impediments to acceptance of the ultraviolet-B-vitamin D-cancer hypothesis.
    Grant WB, Boucher BJ.
    Anticancer Res. 2009 Sep;29(9):3597-604.
    PMID: 19667154

    The ultraviolet-B (UVB)-vitamin D-cancer hypothesis was proposed in 1980. There have been numerous ecological, observational and other studies of the hypothesis. There are about 14 types of cancer for which it seems to apply: bladder, breast, colon, endometrial, esophageal, gallbladder, gastric, ovarian, pancreatic, rectal, renal and vulvar cancer and both Hodgkin's and non-Hodgkin's lymphoma. Nonetheless, the hypothesis has not yet been accepted by public health agencies. Some of the reasons for this include a distrust of ecological studies, some mistrust of observational studies, and the existence of just one positive randomized controlled trial, an analysis of a vitamin D and calcium supplementation study involving post-menopausal women in Nebraska. Paradigm shifts such as this generally take time, in part due to opposition from those content with the status quo. In this paper, results of ecological studies in the United States using summertime solar UVB as the index of vitamin D production, which is highly asymmetrical with respect to latitude, and indices for other cancer risk-modifying factors (air pollution, alcohol consumption, dietary iron and zinc, ethnic background, socioeconomic status, smoking and urban/rural residence) are discussed in terms of supporting the hypothesis. These studies were not considered while other ecological studies were examined in recent critiques of the hypothesis. While additional randomized controlled trials would, of course, be helpful, the current evidence seems to satisfy the criteria for causality as outlined by A. Bradford Hill.
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