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Matti Narkia

Vitamin D, aging, and cancer. Pentti Tuohimaa. 2008; Nutrition Reviews - Wiley InterSci... - 0 views

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    Vitamin D, aging, and cancer. Tuohimaa P. Nutr Rev. 2008 Oct;66(10 Suppl 2):S147-52. Review. PMID: 18844842 DOI: 10.1111/j.1753-4887.2008.00095.x Deficiency of the prohormone calcidiol (25OH vitamin D3) seems to be associated with several aging-related chronic diseases including cancer. Our results suggest that calcidiol is mainly responsible for differentiation homeostasis, whereas calcitriol might be more involved in calcium homeostasis. Therefore, an imbalance of calcidiol rather than calcitriol is a risk factor for cancer and chronic diseases. Calcidiol insufficiency, as well as insufficient solar exposure, is associated with increased risk of several solid cancers. Both a vitamin D3 deficiency and a high concentration of calcidiol may increase cancer risk. Similarly, aging phenomena show a U-shaped association with vitamin D bioactivity. Therefore, the chronic diseases and cancers related to aging might be prevented by an optimal concentration of serum calcidiol, which remains to be determined.
Matti Narkia

Estimation of the dietary requirement for vitamin D in free-living adults >=64 y of age... - 0 views

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    Estimation of the dietary requirement for vitamin D in free-living adults >=64 y of age. Cashman KD, Wallace JM, Horigan G, Hill TR, Barnes MS, Lucey AJ, Bonham MP, Taylor N, Duffy EM, Seamans K, Muldowney S, Fitzgerald AP, Flynn A, Strain JJ, Kiely M. Am J Clin Nutr. 2009 May;89(5):1366-74. Epub 2009 Mar 18. PMID: 19297462 doi:10.3945/ajcn.2008.27334 Conclusion: To ensure that the vitamin D requirement is met by the vast majority (>97.5%) of adults aged ≥64 y during winter, between 7.9 and 42.8 µg vitamin D/d is required, depending on summer sun exposure and the threshold of adequacy of 25(OH)D. .
Matti Narkia

Serum 25-hydroxyvitamin D status of vegetarians, partial vegetarians, and nonvegetarian... - 0 views

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    Serum 25-hydroxyvitamin D status of vegetarians, partial vegetarians, and nonvegetarians: the Adventist Health Study-2. Chan J, Jaceldo-Siegl K, Fraser GE. Am J Clin Nutr. 2009 May;89(5):1686S-1692S. Epub 2009 Apr 1. PMID: 19339396 Conclusions: s25(OH)D concentrations were not associated with vegetarian status. Other factors, such as vitamin D supplementation, degree of skin pigmentation, and amount and intensity of sun exposure have greater influence on s25(OH)D than does diet.
Matti Narkia

Do we need more sunlight to make enough vitamin D? « Cancer Research UK - Sci... - 0 views

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    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.
Matti Narkia

The roles of calcium and vitamin D in skeletal health: an evolutionary perspective - Ro... - 0 views

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    Robert P. Heaney is John A. Creighton University Professor, Creighton University, Omaha, Nebraska, United States. Hominid evolution took place in an environment (equatorial East Africa) that provided a superabundance of both calcium and vitamin D, the first in available foods and the second through conversion of 7-dehydrocholesterol to pre-vitamin D in the skin, a reaction catalysed by the intense solar ultraviolet (UV) radiation. Seemingly as a consequence, the evolving human physiology incorporated provisions to prevent the potential of toxic excesses of both nutrients. For vitamin D the protection was of two sorts: skin pigmentation absorbed the critical UV wavelengths and thereby limited dermal synthesis of cholecalciferol; and slow delivery of vitamin D from the skin into the bloodstream left surplus vitamin in the skin, where continuing sun exposure led to its photolytic degradation to inert compounds. For calcium, the adaptation consisted of very inefficient calcium absorption, together with poor to absent systemic conservation. The latter is reflected in unregulated dermal calcium losses, a high sensitivity of renal obligatory calcium loss to other nutrients in the diet and relatively high quantities of calcium in the digestive secretions. Today, chimpanzees in the original hominid habitat have diets with calcium nutrient densities in the range of 2 to 2.5 mmol per 100 kcal, and hunter-gatherer humans in Africa, South America and New Guinea still have diets very nearly as high in calcium (1.75 to 2 mmol per 100 kcal) (Eaton and Nelson, 1991). With energy expenditure of 3 000 kcal per day (a fairly conservative estimate for a contemporary human doing physical work), such diets would provide substantially in excess of 50 mmol of calcium per day. By contrast, median intake in women in North America and in many European countries today is under 15 mmol per day. Two factors altered the primitive situation: the migration of humans from Africa to higher latitude
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 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

Vitamin D Newsletter March 2009 | All Things Vitamin D - 0 views

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    This is a very long newsletter. I will answer questions about oil versus water-soluble Vitamin D, depression, mental clarity, malignant melanoma, Crohn's disease, an imagist poet, multiple sclerosis, sun-exposure, high-intensity red light and collagen repair in the skin, non-alcoholic fatty liver disease, influenza, the 1918 influenza pandemic, statins, the new Food and Nutrition Board, thyroid disease, chronic fatigue syndrome, athletes, the upcoming 14th Vitamin D Workshop, prostate cancer, the wrong blood test, pregnancy, autism, Alzheimer's disease, soap and sebum, asthma, sleep, the co-factors vitamin D needs to work (all contained in spinach), and-my favorite-UVC light and Vitamin D
Matti Narkia

Vitamin D and Cancer - 0 views

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    This web site is dedicated to vitamin D and cancer. This is because exciting new research indicates that vitamin D-whether produced in the skin as a result of exposure to ultraviolet radiation (from sunlight or sun lamps) or obtained from supplementation with cholecalciferol (vitamin D3)-may help cancer patients. However, the research is far from complete.
Matti Narkia

Lack of sunshine found to trigger multiple sclerosis | Society | guardian.co.uk - 0 views

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    Research finds people with gene variant who lack vitamin D, produced from sun exposure, can develop condition
Matti Narkia

BBC NEWS | Health | Vitamin D 'is mental health aid' - 0 views

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    Vitamin D, found in fish and produced by sun exposure, can help stave off the mental decline that can affect people in old age, a study has suggested. UK and US researchers looked at 2,000 people aged 65 and over.
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

Athletic Performance and Vitamin D : Medicine & Science in Sports & Exercise - 0 views

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    Athletic performance and vitamin D. Cannell JJ, Hollis BW, Sorenson MB, Taft TN, Anderson JJ. Med Sci Sports Exerc. 2009 May;41(5):1102-10. Review. PMID: 19346976 doi: 10.1249/MSS.0b013e3181930c2b Conclusions: Vitamin D may improve athletic performance in vitamin D-deficient athletes. Peak athletic performance may occur when 25(OH)D levels approach those obtained by natural, full-body, summer sun exposure, which is at least 50 ng·mL-1. Such 25(OH)D levels may also protect the athlete from several acute and chronic medical conditions.
Matti Narkia

W.O.W. 11/15/09 (and a little D3) » - 0 views

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    "Last Wednesday night I gave a lecture to my clients on hunter-gatherer diets. The turnout was great and the information was well-received. I had it professionally video-recorded and will probably offer this as a DVD for sale (with the handout included). Watch for it in the future. Part of what I discussed was vitamin D3 supplementation. Since I have been supplementing with 4,000-10,000 Units of D3 per day I have noted enhanced recovery and size response from my training. Apparently, skeletal muscle has both surface receptors and nuclear receptors for D3 that augment calcium flux during contraction (from surface receptors) and have steroid-like effects at the nuclear level WRT protein synthesis. This D3 supplementation is not really "supplementation" but is instead "augmentation" to levels that would be normal if we got normal sun exposure as we did in our evolutionary past. Check out www.vitamindcouncil.org for more information. Also, check out this abstract below for your consideration. Also, check out this article."
Matti Narkia

Evo and Proud: African Americans and vitamin D - 0 views

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    "It's well known that African Americans have low levels of vitamin D in their blood. In fact, this seems to be generally true for humans of tropical origin. In a study from Hawaii, vitamin D status was assessed in healthy, visibly tanned young adults who averaged 22.4 hours per week of unprotected sun exposure. Yet 51% had levels below the current recommended minimum of 75 nmol/L (Binkley et al., 2007). In a study from south India, levels below 50 nmol/L were found in 44% of the men and 70% of the women. The subjects are described as "agricultural workers starting their day at 0800 and working outdoors until 1700 with their face, chest, back, legs, arms, and forearms exposed to sunlight" (Harinarayan et al., 2007). In a study from Saudi Arabia, levels below 25 nmol/L were found in respectively 35%, 45%, 53%, and 50% of normal male university students of Saudi, Jordanian, Egyptian, and other origins (Sedrani, 1984)."
Matti Narkia

Vitamin D and Memory - Amen Clinics - 0 views

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    "One of the surprises over the past year has been all the research regarding Vitamin D and brain health. Give that many people are spending less time outdoors and more time in front of their computers, we all should be concerned, as Vitamin D comes in part from our exposure to the sun. Low Vitamin D levels have been associated with pain, depression, MS, cancer and now perhaps even dementia. Here are the results of a new study that should cause all of us to pay attention. I frequently check the Vitamin D levels in my patients and frrequently see that they are below the optimal level. Get your levels checked if you have any of these concerns. A new large-scale senior population study has found that a lack of vitamin D in the elderly could be linked to cognitive impairment. The study, conducted on almost 2,000 adults over the age of 65, is the first of its scale to identify this relationship, and prompted researchers to suggest vitamin D supplementation as a possible means of reducing the risk of dementia. "
Matti Narkia

High-dose vitamin D3 supplementation in a cohort of breastfeeding mothers and their inf... - 0 views

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    High-dose vitamin D3 supplementation in a cohort of breastfeeding mothers and their infants: a 6-month follow-up pilot study. Wagner CL, Hulsey TC, Fanning D, Ebeling M, Hollis BW. Breastfeed Med. 2006 Summer;1(2):59-70. PMID: 17661565 doi:10.1089/bfm.2006.1.59. Objective: To examine the effect of high-dose maternal vitamin D3 (vitD) supplementation on the nutritional vitD status of breastfeeding (BF) women and their infants compared with maternal and infant controls receiving 400 and 300 IU vitD/day, respectively. Design: Fully lactating women (n = 19) were enrolled at 1-month postpartum into a randomized- control pilot trial. Each mother received one of two treatments for a 6-month study period: 0 or 6000 IU vitD3 plus a prenatal vitamin containing 400 IU vitD3. The infants of mothers assigned to the control group received 300 IU vitD3/day; those infants of mothers in the high-dose group received 0 IU (placebo). Maternal serum and milk vitD and 25(OH)D were measured at baseline then monthly; infant serum vitD and 25(OH)D were measured at baseline, and months 4 and 7. Urinary calcium/creatinine ratios were measured monthly in both mothers and infants. Dietary and BF history and outdoor activity questionnaires were completed at each visit. Changes in skin pigmentation were measured by spectrophotometry. Data were analyzed using chi-square, t-test, and analysis of variance (ANOVA) on an intent-to-treat basis. Conclusion: With limited sun exposure, an intake of 400 IU/day vitamin D3 did not sustain circulating maternal 25(OH)D levels, and thus, supplied only extremely limited amounts of vitamin D to the nursing infant via breast milk. Infant levels achieved exclusively through maternal supplementation were equivalent to levels in infants who received oral vitamin D supplementation. Thus, a maternal intake of 6400 IU/day vitamin D elevated circulating 25(OH)D in both mother and nursing infant.
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

The Association of Solar Ultraviolet B (UVB) with Reducing Risk of Cancer: Multifactori... - 0 views

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    The association of solar ultraviolet B (UVB) with reducing risk of cancer: multifactorial ecologic analysis of geographic variation in age-adjusted cancer mortality rates. Grant WB, Garland CF. Anticancer Res. 2006 Jul-Aug;26(4A):2687-99. PMID: 16886679 CONCLUSION: These results provide additional support for the hypothesis that solar UVB, through photosynthesis of vitamin D, is inversely-associated with cancer mortality rates, and that various other cancer risk-modifying factors do not detract from this link. It is thought that sun avoidance practices after 1980, along with improved cancer treatment, led to reduced associations in the latter period. The results regarding solar UVB should be studied further with additional observational and intervention studies of vitamin D indices and cancer incidence, mortality and survival rates.
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.
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