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Improved cholecalciferol nutrition in rats is noncalcemic, suppresses parathyroid hormone and increases responsiveness to 1, 25-dihydroxycholecalciferol. Vieth R, Milojevic S, Peltekova V. J Nutr. 2000 Mar;130(3):578-84. PMID: 10702588 We conclude suppression of 1,25(OH)(2)D and PTH, and higher renal VDR mRNA and 24-hydroxylase did not involve higher free 1,25(OH)(2)D concentration or a first pass effect at the gut. Thus, 25(OH)D or a metabolite other than 1,25(OH)(2)D is a physiological, transcriptionally and biochemically active, noncalcemic vitamin D metabolite. When viewed from a perspective that starts with higher vitamin D nutrition, the results indicate that low vitamin D nutrition may bring about a form of resistance to 1,25(OH)2D. This situation would explain why, in humans, nutritional rickets and osteomalacia are commonly associated with normal or increased levels of 1,25(OH)2D (Chesney et al. 1981Citation , Eastwood et al. 1979Citation , Garabedian et al. 1983Citation ,Rasmussen et al. 1980Citation )-these are not like the low hormone levels associated with any other endocrine-deficiency disorder. A connection between lower vitamin D nutrition and vitamin D resistance helps to explain why the supposedly inactive compound 25(OH)D is more relevant in diagnosing nutritional rickets than is the active hormone 1,25(OH)2D. If the features of improved vitamin D nutrition shown here were demonstrated for any newly synthesized compound, the compound would be classified as a noncalcemic 1,25(OH)2D analogue (Brown et al. 1989Citation , Finch et al. 1999Citation , Goff et al. 1993Citation , Koshizuka et al. 1999Citation ). Thus, we contend that 25(OH)D or a metabolite of it other than 1,25(OH)2D exists as a physiological and biologically-active noncalcemic vitamin D metabolite whose effects require further examination, particularly in relationship to studies involving the synthetic analogs of 1,25(OH)2D.

Dark chocolate consumption increases HDL cholesterol concentration and chocolate fatty acids may inhibit lipid peroxidation in healthy humans. Mursu J, Voutilainen S, Nurmi T, Rissanen TH, Virtanen JK, Kaikkonen J, Nyyssönen K, Salonen JT. Free Radic Biol Med. 2004 Nov 1;37(9):1351-9. PMID: 15454274 doi:10.1016/j.freeradbiomed.2004.06.002 Cocoa polyphenols may increase the concentration of HDL cholesterol, whereas chocolate fatty acids may modify the fatty acid composition of LDL and make it more resistant to oxidative damage.

High dietary methionine intake increases the risk of acute coronary events in middle-aged men. Virtanen JK, Voutilainen S, Rissanen TH, Happonen P, Mursu J, Laukkanen JA, Poulsen H, Lakka TA, Salonen JT. Nutr Metab Cardiovasc Dis. 2006 Mar;16(2):113-20. Epub 2005 Nov 2. PMID: 16487911 doi:10.1016/j.numecd.2005.05.005 Conclusions The main finding of this study is that long-term, moderately high dietary methionine intake may increase the risk of acute coronary events in middle-aged Finnish men free of prior CHD. More prospective research is needed to confirm the role of dietary methionine in the development of CVD, and whether its effects are independent of homocysteine.

Bread fortified with cholecalciferol increases the serum 25-hydroxyvitamin D concentration in women as effectively as a cholecalciferol supplement. Natri AM, Salo P, Vikstedt T, Palssa A, Huttunen M, Kärkkäinen MU, Salovaara H, Piironen V, Jakobsen J, Lamberg-Allardt CJ. J Nutr. 2006 Jan;136(1):123-7. PMID: 16365070 Both fortified breads increased serum 25-hydroxyvitamin D concentration as effectively as the cholecalciferol supplement. Supplementation or fortification did not affect serum intact parathyroid hormone concentration or urinary calcium excretion. In conclusion, fortified bread is a safe and feasible way to improve vitamin D nutrition.

Depression is associated with decreased 25-hydroxyvitamin D and increased parathyroid hormone levels in older adults. Hoogendijk WJ, Lips P, Dik MG, Deeg DJ, Beekman AT, Penninx BW. Arch Gen Psychiatry. 2008 May;65(5):508-12. PMID: 18458202 Conclusion The results of this large population-based study show an association of depression status and severity with decreased serum 25(OH)D levels and increased serum PTH levels in older individuals.

A prospective nested case-control study of vitamin D status and pancreatic cancer risk in male smokers. Stolzenberg-Solomon RZ, Vieth R, Azad A, Pietinen P, Taylor PR, Virtamo J, Albanes D. Cancer Res. 2006 Oct 15;66(20):10213-9. PMID: 17047087 Higher vitamin D concentrations were associated with a 3-fold increased risk for pancreatic cancer (highest versus lowest quintile, >65.5 versus <32.0 nmol/L: OR, 2.92; 95% CI, 1.56-5.48, Ptrend = 0.001) that remained after excluding cases diagnosed early during follow-up. Contrary to expectations, subjects with higher prediagnostic vitamin D status had an increased pancreatic cancer risk compared with those with lower status. Our findings need to be replicated in other populations and caution is warranted in their interpretation and implication. Our results are intriguing and may provide clues that further the understanding of the etiology of this highly fatal cancer. In conclusion, contrary to expectation, subjects with higher 25(OH)D concentrations were at greater risk for pancreatic cancer compared with those with lower concentrations in our prospective study with long-term follow-up. Caution is warranted in the interpretation and implication of our findings, however, as vitamin D inadequacy is an important public health problem and adequate status is desirable to prevent bone and other diseases (5). Our results, however, are intriguing and may provide clues that further the understanding of the etiology of this highly fatal cancer.

Serum vitamin D concentration and prostate cancer risk: a nested case-control study. Ahn J, Peters U, Albanes D, Purdue MP, Abnet CC, Chatterjee N, Horst RL, Hollis BW, Huang WY, Shikany JM, Hayes RB; Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Project Team. J Natl Cancer Inst. 2008 Jun 4;100(11):796-804. Epub 2008 May 27. PMID: 18505967 doi:10.1093/jnci/djn152 CONCLUSION: The findings of this large prospective study do not support the hypothesis that vitamin D is associated with decreased risk of prostate cancer; indeed, higher circulating 25(OH)D concentrations may be associated with increased risk of aggressive disease. In summary, results from this large prospective study of men who underwent standardized prostate cancer screening in the context of a screening trial do not support the hypothesis that higher serum vitamin D status is associated with decreased risk of prostate cancer. The study showed no association of vitamin D level with nonaggressive disease; however, it raises the possibility that higher vitamin D level may be associated with increased risks for aggressive disease, although a clear monotonic dose-response relationship was lacking. Along with recent reports of adverse associations for higher vitamin D status and risk of pancreatic (32) and esophageal (33,34) cancer, caution should be taken in recommending high doses of vitamin D or sunlight exposure to the general public for prostate cancer prevention. Future analyses are warranted to confirm these results and to further clarify the effects of vitamin D on aggressive prostate cancer.

"DALLAS, Jan. 8 - The same vitamin D deficiency that can result in weak bones now has been associated with an increased risk of cardiovascular disease, Framingham Heart Study researchers report in Circulation: Journal of the American Heart Association. "Vitamin D deficiency is associated with increased cardiovascular risk, above and beyond established cardiovascular risk factors," said Thomas J. Wang, M.D., assistant professor of medicine at Harvard Medical School in Boston, Mass. "The higher risk associated with vitamin D deficiency was particularly evident among individuals with high blood pressure." In a study of 1,739 offspring from Framingham Heart Study participants (average age 59, all Caucasian), researchers found that those with blood levels of vitamin D below15 nanograms per milliliter (ng/mL) had twice the risk of a cardiovascular event such as a heart attack, heart failure or stroke in the next five years compared to those with higher levels of vitamin D."

Vitamin D replacement in Asians with diabetes may increase insulin resistance. Taylor AV, Wise PH. Postgrad Med J. 1998 Jun;74(872):365-6. PMID: 9799895 We report three cases of vitamin D replacement in British Asians with vitamin D deficiency and non-insulin-dependent diabetes mellitus. In all cases, replacement resulted in an increase in insulin resistance and a deterioration of glycaemic control

By integrating better meals in your body, explore only increase your health, but additionally increase the look and feel of the skin and give you an effective blush. So in lieu of trying to read all of the chemicals around the labels, try eating healthy first.

Increased intake of vitamin C-rich foods may reduce the risk of hardening of the arteries, and ultimately protect against heart disease, says a new study from Norway.\nWriting in the journal Nutrition, Metabolism and Cardiovascular Diseases, researchers from Ulleval University Hospital in Norway report that increased intakes of vitamin C and fruit and berries were associated with less thickening of the carotid artery.

A glass of wine each evening is enough to increase your risk of developing cancer, women are being warned.\nConsuming just one drink a day causes an extra 7,000 cancer cases - mostly breast cancer - in UK women each year, Cancer Research UK scientists say

Increased intakes of vitamin K2, but not vitamin K1, may decrease the risk of coronary heart disease in postmenopausal women, says a new study.\nFor every 10 microgram increase in the amount of vitamin K2 consumed, researchers from the Netherlands report a 9 per cent reduction in the risk of developing coronary heart disease (CHD).

I take ground flaxseed to help control my cholesterol. But I read that the alpha-linoleic acid (ALA) in flax increases the risk of prostate cancer. Is this true? Does the risk differ between ground flaxseed and concentrated flaxseed oil in capsules? John

Amsterdam, The Netherlands, May 26, 2009 - There are several risk factors for the development of Alzheimer's disease and vascular dementia. Based on an increasing number of studies linking these risk factors with Vitamin D deficiency, an article in the current issue of the Journal of Alzheimer's Disease (May 2009) by William B. Grant, PhD of the Sunlight, Nutrition, and Health Research Center (SUNARC) suggests that further investigation of possible direct or indirect linkages between Vitamin D and these dementias is needed. Low serum levels of 25-hydroxyvitamin D [25(OH)D] have been associated with increased risk for cardiovascular diseases, diabetes mellitus, depression, dental caries, osteoporosis, and periodontal disease, all of which are either considered risk factors for dementia or have preceded incidence of dementia. In 2008, a number of studies reported that those with higher serum 25(OH)D levels had greatly reduced risk of incidence or death from cardiovascular diseases

Increased intakes of vitamins C and E and beta-carotene may reduce the risk of cancer of the uterus, according to a new review and meta-analysis of the science to date. Writing in Cancer Causes and Control, US scientists report that for every 1,000 microgram increase per 1,000 kcal of diet of beta-carotene was associated with a 12 per cent reduction in the risk of endometrial cancer.

25-hydroxyvitamin D levels inversely associate with risk for developing coronary artery calcification. de Boer IH, Kestenbaum B, Shoben AB, Michos ED, Sarnak MJ, Siscovick DS. J Am Soc Nephrol. 2009 Aug;20(8):1805-12. Epub 2009 May 14. PMID: 19443637 doi: 10.1681/ASN.2008111157 "In conclusion, lower 25-hydroxyvitamin D concentrations associate with increased risk for incident CAC. Accelerated development of atherosclerosis may underlie, in part, the increased cardiovascular risk associated with vitamin D deficiency."

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.

Optimal vitamin D status attenuates the age-associated increase in systolic blood pressure in white Americans: results from the third National Health and Nutrition Examination Survey. Judd SE, Nanes MS, Ziegler TR, Wilson PW, Tangpricha V. Am J Clin Nutr. 2008 Jan;87(1):136-41. PMID: 18175747 Conclusions: SBP is inversely associated with serum vitamin D concentrations in nonhypertensive white persons in the United States. This observation provides a rationale for studies on the potential effects of vitamin D supplementation as a method to reduce SBP in persons at risk of hypertension.