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A Lecture by Reinhold Vieth, Professor, Departments of Nutritional Sciences and Laboratory Medicine and Pathobiology, Mount Sinai Hospital. Presentation Date: Friday, October 21, 2005 (works in Internet Explorer, but not properly in Firefox (slides don't change in Firefox)).

Vitamin D-induced up-regulation of tumour necrosis factor alpha (TNF-alpha) in prostate cancer cells. Golovko O, Nazarova N, Tuohimaa P. Life Sci. 2005 Jun 17;77(5):562-77. Epub 2005 Feb 25. PMID: 15904673 doi:10.1016/j.lfs.2004.10.072 Combined addition of human recombinant TNF-alpha with calcitriol or CB1093 cause enhanced effect in induction of apoptosis. We conclude that under physiological conditions vitamin D activates only the transcription of TNF-alpha gene, for TNF-alpha protein synthesis additional cofactors are required. Therefore a cooperation of vitamin D and TNF-alpha may play an important role in the control of cell growth in prostate cancer.

Professor Departments of Nutritional Sciences, Laboratory Medicine, and Pathobiology, Bone and Mineral Laboratory, Pathology and Laboratory Medicine, University of Toronto, Toronto, Canada M5S 3E2 Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario, Canada

"D-vitamiinin saantisuositus moninkertaistettava Kansainvälinen paine D-vitamiinin saantisuosituksen korottamiseksi kasvaa. Suomessa viranomaissuositus aikuisille on 7,5 mikrogrammaa. Kalifornian yliopiston 18-henkinen tiedemiesryhmä vaatii suosituksen nostamista 2000 kansainväliseen yksikköön eli 50 mikrogrammaan. Suiomessa Pekka Puska haraa vastaan. Tohtori Anthony W. Norman ja hänen tiedemiesryhmänsä kutsuvat maailman muita tutkijoita toimiin ("call to action") aikuisten ihmisten D-vitamiinin saantisuosituksen nostamiseksi 50 mikrogrammaan päivässä. Normanin laatima pääkirjoitus D-vitamiinista julkaistiin joulukuun American Journal of Nutritionissa (linkki lopussa). "Päättäjien on syytä perehtyä tieteellisiin tutkimuksiin, jotka puoltavat suosituksen nostamista", sanoo tiedemiesryhmä. Se suosittelee elintarvikkeiden rikastamista D-vitamiinilla ja D-vitamiinin käyttöä ravintolisänä. Yhdysvalloissa viranomaissuositus on alle 50-vuotiaille aikuisille 5 µg, 51-70 -vuotiaille 10 µg ja yli 70-vuotiaille 15 µg. Suomessa suositus on 7,5 µg alle 60-vuotiaille ja 10 µg sitä vanhemmille. "Amerikkalaiset tiedemiehet allekirjoittivat lausunnon, jonka mukaan aikuisen [amerikkalaisen] ihmisen D3-vitamiinin tarve on 2000 kansainvälistä yksikköä [eli 50 mikrogrammaa] vuorokaudessa", sanoo Norman. "Suositeltu annos on täysin turvallinen", hän korostaa ja viittaa Yhdysvaltain tiedeakatemian (National Academy of Sciences) lausuntoon."

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.

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

Vitamin D: In the evolution of human skin colour. Yuen AW, Jablonski NG. Med Hypotheses. 2009 Aug 28. [Epub ahead of print] PMID: 19717244

Food chain as origin of vitamin D in fish D. Sunita Rao and N. Raghuramulu. Comparative Biochemistry and Physiology Part A: Physiology Volume 114, Issue 1, May 1996, Pages 15-19 doi:10.1016/0300-9629(95)02024-1 Plankton, the chief food source of fish, was assessed as the possible dietary origin of vitamin D in fish. The presence of vitamin D compounds were examined in fresh water phytoplankton and zooplankton employing a series of chromatographic procedures. Abundant amounts of provitamins D and vitamins D (D2 and D3) were found in the fresh water plankton. The high amount of vitamin D observed may be due to exposure of plankton to sunlight because the plankton were caught during the summer month. Thus, plankton may be an important contributor to vitamin D in fish.

Environmental risk factors for autism: Do they help cause de novo genetic mutations that contribute to the disorder? Kinney DK, Barch DH, Chayka B, Napoleon S, Munir KM. Med Hypotheses. 2009 Aug 20. [Epub ahead of print] PMID: 19699591

Vitamin D, nervous system and aging. Tuohimaa P, Keisala T, Minasyan A, Cachat J, Kalueff A. Psychoneuroendocrinology. 2009 Aug 4. [Epub ahead of print] PMID: 19660871

Review article: vitamin D acquisition and breast cancer risk. Pérez-López FR, Chedraui P, Haya J. Reprod Sci. 2009 Jan;16(1):7-19. Review. PMID: 19144887 DOI: 10.1177/1933719108327595 Conclusions: Although there are controversial results, it seems plausible that sufficient endogenous vitamin D levels may have a protective function on mammary cells, reducing breast cancer risk.

This month, the authoritative International Agency for Research into Cancer (IARC) have weighed in on the issue. By gathering a group of expert scientists, they have looked at all the available evidence and published a detailed report on vitamin D and cancer. The massive tome weighs in at 465 pages, but we'll take a look at the key points in the first of two posts looking at the vitamin D debate. It is impossible for us to get more than about five percent of the vitamin D we need from our diet - unless, like Eskimos, we eat oily fish three times a day.

In the last post, we talked about the new report on vitamin D and cancer from the International Agency for Research into Cancer (IARC). In this one, we'll summarise what the report has to say on the balance between getting enough vitamin D through sun exposure and reducing the risk of skin cancer by being SunSmart. IARC calls for more trials to really pin down the effects of vitamin D supplements - either positive or negative - depending on how much vitamin D people already have in their system. Until then, they feel that there is no solid basis for changing any existing recommendations about vitamin D.

White Europeans could have evolved as recently as 5,500 years ago, according to research which suggests that the early humans who populated Britain and Scandinavia had dark skins for millenniums. It was only when early humans gave up hunter-gathering and switched to farming about 5,500 years ago that white skin began to be favoured, say the researchers. This is because farmed food was deficient in vitamin D, a vital nutrient. Humans can make this in their skin when exposed to sunlight, but dark skin is much less efficient at it.

Calcidiol and prostate cancer. Tuohimaa P, Golovko O, Kalueff A, Nazarova N, Qiao S, Syvälä H, Talonpoika R, Lou YR. J Steroid Biochem Mol Biol. 2005 Feb;93(2-5):183-90. Epub 2005 Jan 22. Review. PMID: 15860261

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

An evaluation of the vitamin D3 content in fish: Is the vitamin D content adequate to satisfy the dietary requirement for vitamin D?\nLu Z, Chen TC, Zhang A, Persons KS, Kohn N, Berkowitz R, Martinello S, Holick MF.\nJ Steroid Biochem Mol Biol. 2007 Mar;103(3-5):642-4. Epub 2007 Jan 30.\nPMID: 17267210 \ndoi:10.1016/j.jsbmb.2006.12.010 \n

Vitamin D and Cancer Mini-Symposium: The Risk of Additional Vitamin D. Vieth R. Ann Epidemiol. 2009 Apr 11. [Epub ahead of print] PMID: 19364661 doi:10.1016/j.annepidem.2009.01.009