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Bioactive vitamin D or calcitriol is a steroid hormone that has long been known for its important role in regulating body levels of calcium and phosphorus, and in mineralization of bone. More recently, it has become clear that receptors for vitamin D are present in a wide variety of cells, and that this hormone has biologic effects which extend far beyond control of mineral metabolism. The active form of vitamin D binds to intracellular receptors that then function as transcription factors to modulate gene expression. Like the receptors for other steroid hormones and thyroid hormones, the vitamin D receptor has hormone-binding and DNA-binding domains. The vitamin D receptor forms a complex with another intracellular receptor, the retinoid-X receptor, and that heterodimer is what binds to DNA. In most cases studied, the effect is to activate transcription, but situations are also known in which vitamin D suppresses transcription. Each of the forms of vitamin D is hydrophobic, and is transported in blood bound to carrier proteins. The major carrier is called, appropriately, vitamin D-binding protein. The halflife of 25-hydroxycholecalciferol is several weeks, while that of 1,25-dihydroxycholecalciferol is only a few hours. The vitamin D receptor binds several forms of cholecalciferol. Its affinity for 1,25-dihydroxycholecalciferol is roughly 1000 times that for 25-hydroxycholecalciferol, which explains their relative biological potencies

Effects of Atorvastatin on vitamin D levels in patients with acute ischemic heart disease. Pérez-Castrillón JL, Vega G, Abad L, Sanz A, Chaves J, Hernandez G, Dueñas A. Am J Cardiol. 2007 Apr 1;99(7):903-5. Epub 2007 Feb 8. PMID: 17398180 In conclusion, atorvastatin increases vitamin D levels. This increase could explain some of the beneficial effects of atorvastatin at the cardiovascular level that are unrelated to cholesterol levels. The mechanism by which atorvastatin increases vitamin D levels is related to inhibition of 3-hydroxy-3 methylglutaryl coenzyme A (HMG-CoA) reductase. Cholesterol is synthesized from 7-dehydrocholesterol, which is also a precursor of vitamin D3. For this reason, we initially observed a statistically significant relation between total cholesterol and vitamin D. HMG-CoA enzyme reductase is key to the synthesis of cholesterol, whereas ultraviolet radiation causes the formation of 25-hydroxyvitamin D. Inhibition of the enzyme may increase levels of 7-dehydrocholesterol and increase the synthesis of 25-hydroxycholecalciferol, thereby increasing vitamin D levels,10 although we observed no relation between lower cholesterol and increased vitamin D. In addition, 25-hydroxyvitamin D has been shown to inhibit HMG-CoA enzyme reductase activity in in vitro studies.11 A greater concentration of vitamin D could increase enzymatic inhibition, acting in synergy with the statin in decreasing total cholesterol.

Effects of vitamin D and calcium supplementation on falls: a randomized controlled trial. Bischoff HA, Stähelin HB, Dick W, Akos R, Knecht M, Salis C, Nebiker M, Theiler R, Pfeifer M, Begerow B, Lew RA, Conzelmann M. J Bone Miner Res. 2003 Feb;18(2):343-51. PMID: 12568412 A single intervention with vitamin D plus calcium over a 3-month period reduced the risk of falling by 49% compared with calcium alone. Over this short-term intervention, recurrent fallers seem to benefit most by the treatment. The impact of vitamin D on falls might be explained by the observed improvement in musculoskeletal function.

Vitamin D supplementation improves neuromuscular function in older people who fall. Dhesi JK, Jackson SH, Bearne LM, Moniz C, Hurley MV, Swift CG, Allain TJ. Age Ageing. 2004 Nov;33(6):589-95. PMID: 15501836 doi:10.1093/ageing/afh20 9 CONCLUSIONS: vitamin D supplementation, in fallers with vitamin D insufficiency, has a significant beneficial effect on functional performance, reaction time and balance, but not muscle strength. This suggests that vitamin D supplementation improves neuromuscular or neuroprotective function, which may in part explain the mechanism whereby vitamin D reduces falls and fractures.

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.

Now a new and controversial book by an American doctor suggests that taking even higher levels of the vitamin - 10 to 15 times the recommended amounts - can work wonders. Dr James Dowd, who works at the Arthritis Institute of Michigan, has been prescribing vitamin D to people suffering from chronic disorders such as arthritis, back pain and headaches and the result, he claims, is a huge improvement in their symptoms. In his book, The Vitamin D Cure, Dr Dowd describes a number of success stories using this approach. One of his patients, Barbara, for instance, was obese, and suffered from arthritis in one leg as well as high blood pressure. As Dowd explains: "In the past I would have given her anti-inflammatory drugs, pain medication, a pill to lose weight and drug treatment for hypertension."

Benfotiamine, a synthetic S-acyl thiamine derivative, has different mechanisms of action and a different pharmacological profile than lipid-soluble thiamine disulfide derivatives. Volvert ML, Seyen S, Piette M, Evrard B, Gangolf M, Plumier JC, Bettendorff L. BMC Pharmacol. 2008 Jun 12;8:10. PMID: 18549472 doi:10.1186/1471-2210-8-10 Conclusion Our results show that, though benfotiamine strongly increases thiamine levels in blood and liver, it has no significant effect in the brain. This would explain why beneficial effects of benfotiamine have only been observed in peripheral tissues, while sulbutiamine, a lipid-soluble thiamine disulfide derivative, that increases thiamine derivatives in the brain as well as in cultured cells, acts as a central nervous system drug. We propose that benfotiamine only penetrates the cells after dephosphorylation by intestinal alkaline phosphatases. It then enters the bloodstream as S-benzoylthiamine that is converted to thiamine in erythrocytes and in the liver. Benfotiamine, an S-acyl derivative practically insoluble in organic solvents, should therefore be differentiated from truly lipid-soluble thiamine disulfide derivatives (allithiamine and the synthetic sulbutiamine and fursultiamine) with a different mechanism of absorption and different pharmacological properties.

Serum tumor necrosis factor-alpha concentrations are negatively correlated with serum 25(OH)D concentrations in healthy women. Peterson CA, Heffernan ME. J Inflamm (Lond). 2008 Jul 24;5:10. PMID: 18652680 doi:10.1186/1476-9255-5-10 Conclusion Serum 25(OH)D status is inversely related to TNF-α concentrations in healthy women, which may in part explain this vitamin's role in the prevention and treatment of inflammatory diseases. Results gleaned from this investigation also support the need to re-examine the biological basis for determining optimal vitamin D status.

ScienceDaily (Apr. 8, 2009) - Deficiency in vitamin D has been widely regarded as contributing to autoimmune disease, but a review appearing in Autoimmunity Reviews explains that low levels of vitamin D in patients with autoimmune disease may be a result rather than a cause of disease and that supplementing with vitamin D may actually exacerbate autoimmune disease.

As the graphic (right) indicates, carbohydrates can be converted to fat, but not vice versa. A net synthesis of carbohydrates from fat cannot occur in our body. This is important. It implies that certain carbohydrates can be more dangerous to our health than fat! However, too much of either food type is detrimental to our health, and too much of both types can result in an even more serious assault on our health. We explain below

Vitamin K2 is produced by animal tissues, including the mammary glands, from vitamin K1, which occurs in rapidly growing green plants. A growing body of published research confirms Dr. Price's discoveries, namely that vitamin K2 is important for the utilization of minerals, protects against tooth decay, supports growth and development, is involved in normal reproduction, protects against calcification of the arteries leading to heart disease, and is a major component of the brain. Vitamin K2 works synergistically with the two other "fat-soluble activators" that Price studied, vitamins A and D. Vitamins A and D signal to the cells to produce certain proteins and vitamin K then activates these proteins. Vitamin K2 plays a crucial role in the development of the facial bones, and its presence in the diets of nonindustrialized peoples explains the wide facial structure and freedom from dental deformities that Weston Price observe

The material presented on this site comes from individuals with years of hard-won experience either practicing alternative diets or observing those who do. As you'll find, no two writers will necessarily agree on all topics. A unifying theme, however, is the intent to squarely acknowledge and discuss the sometimes serious problems that can occur on alternative diets but often go unreported, and to go beyond the simplistic dogmas readily available elsewhere--in fact almost everywhere--to "explain them away." A sense of admirable idealism is often a motivating factor encouraging people to take responsibility for their own health and to explore different diets. However, the development of emotional attachments to philosophies underlying such diets can often end up becoming far more important for some individuals than the results they obtain--or fail to. One result has been widespread refusal in the alternative diet community to face health and behavioral problems that may arise on these diets. A common thread in what you'll read here is that a kind of subjective, "blinded naturalism" has become more or less endemic in the vegetarian, raw-food, and alternative diet movements, which can lead to serious health troubles.

"Under year round UV exposure conditions (low latitudes, broken line, "High UV") there is no association between 25(OH)D and either prostate or pancreatic cancer. At high latitudes (Solid line, "Low UV") there is a positive association between blood levels of 25(OH)D and these cancers. The average year round levels of 25(OH)D actually tend to be higher in northern latitudes, higher than those where there is year-round solar UVB. Vieth explains that we know almost nothing about the enzymes controlling tissue 1,25(OH)2D levels and much of his discussion is extrapolated from renal enzyme activity."

Obesity and Vitamin D One third of Americans are obese. While much of that epidemic is surely due to playing Nintendo instead of baseball, or the consumption of soft drinks instead of water, does that explain it all? Is it a coincidence that the twin epidemics of obesity and vitamin D deficiency are occurring together?

Are statins analogues of vitamin D? Grimes DS. Lancet. 2006 Jul 1;368(9529):83-6. Review. PMID: 16815382 doi:10.1016/S0140-6736(06)68971-X There are many reasons why the dietary-heart-cholesterol hypothesis should be questioned, and why statins might be acting in some other way to reduce the risk of coronary heart disease. Here, I propose that rather than being cholesterol-lowering drugs per se, statins act as vitamin D analogues, and explain why. This proposition is based on published observations that the unexpected and unexplained clinical benefits produced by statins have also been shown to be properties of vitamin D. It seems likely that statins activate vitamin D receptors.

"November 26, 2008 New evidence may explain why it is that we lose not only our youthful looks, but also our youthful pattern of gene activity with age. A report in the November 26th issue of the journal Cell, a Cell Press publication, reveals that a protein perhaps best known for its role in the life-extending benefits of a low-calorie diet also maintains the stability of the mammalian genome-the complete set of genetic instructions "written" in DNA. The researchers found in studies of mammalian stem cells that the protein SIRT1 controls the packaging of DNA into chromatin, thereby setting the youthful pattern of gene activity by keeping select genes switched off. In response to DNA damage, those SIRT1 proteins leave their posts to go off and assist in the necessary repairs. That change in SIRT1's job description leads to shifts in gene activity that parallel those seen in the aging mouse brain, they show. They suspect similar changes would also be found in other body tissues as well."

"In the September 2009 issue of the journal Advances in Therapy, German researchers report that the addition of omega-3 polyunsaturated fatty acids to the over-the-counter arthritis treatment glucosamine sulfate resulted in improved alleviation of symptoms compared to glucosamine alone. The trial is the first, to the authors' knowledge, to test the combination in patients with osteoarthritis. In their introduction to the article, Joerg Gruenwald and his coauthors explain that a chronic imbalance between the synthesis and degradation of cartilage matrix leads to the loss of joint tissue that occurs in osteoarthritis. Glucosamine and omega-3 fatty acids appear to be successful in adjusting this imbalance in the direction of new cartilage synthesis"

"Summer vs Winter Mode: Explaining AMPK Last year I read an article which made a statement that has not left my mind. The statement went as follows: "You are only good as your mitochondria." In fact, the more a dwell into the details of human metabolism, the more I sense that this is true - especially with the metabolic syndrome. For those who are not familiar with the concept of mitochondria, they are the tiny energy factories within the cells that produce cellular energy through aerobic means (meaning oxygen). Mitochondria utilize oxygen to ultimately produce Adenosine Triphosphate or simply ATP. ATP relays energy by donating a phosphate bond resulting in Adenosine Diphosphate (ADP). Another phosphate release would entail Adenosine Monophosphate or AMP. ATP is one of the main sources of cellular energy in the body

Prospective study of serum 25(OH)-vitamin D concentration and risk of oesophageal and gastric cancers. Chen W, Dawsey SM, Qiao YL, Mark SD, Dong ZW, Taylor PR, Zhao P, Abnet CC. Br J Cancer. 2007 Jul 2;97(1):123-8. Epub 2007 Jun 5. PMID: 17551495 We prospectively examined the relation between pretrial serum vitamin D status and risk of oesophageal and gastric cancers among subjects who developed cancer over 5.25 years of follow-up, including 545 oesophageal squamous cell carcinomas (ESCC), 353 gastric cardia adenocarcinomas, 81 gastric noncardia adenocarcinomas, and an age- and sex-stratified random sample of 1105 subjects. We found no associations for gastric cardia or noncardia adenocarcinoma. Among subjects with low vitamin D status, higher serum 25(OH)D concentrations were associated with significantly increased risk of ESCC in men, but not in women. Further refinements of the analysis did not suggest any factors, which could explain this unexpected result. In conclusion, we found a direct association between higher serum 25(OH)D concentration and increased risk of ESCC in men but not women in a large population-based prospective cohort study from rural China. We found no association with risk of gastric cardia or noncardia adenocarcinoma in either sex. Greater than 50% of our cohort had an inadequate serum 25(OH)D concentration, yet higher concentrations were associated with increased risk of ESCC compared to lower concentrations.

The vitamin D-antimicrobial peptide pathway and its role in protection against infection. Gombart AF. Future Microbiol. 2009 Nov;4:1151-65. PMID: 19895218 Vitamin D deficiency has been correlated with increased rates of infection. Since the early 19th century, both environmental (i.e., sunlight) and dietary sources (cod liver) of vitamin D have been identified as treatments for TB. The recent discovery that vitamin D induces antimicrobial peptide gene expression explains, in part, the 'antibiotic' effect of vitamin D and has greatly renewed interest in the ability of vitamin D to improve immune function. Subsequent work indicates that this regulation is biologically important for the response of the innate immune system to wounds and infection and that deficiency may lead to suboptimal responses toward bacterial and viral infections. The regulation of the cathelicidin antimicrobial peptide gene is a human/primate-specific adaptation and is not conserved in other mammals. The capacity of the vitamin D receptor to act as a high-affinity receptor for vitamin D and a low-affinity receptor for secondary bile acids and potentially other novel nutritional compounds suggests that the evolutionary selection to place the cathelicidin gene under control of the vitamin D receptor allows for its regulation under both endocrine and xenobiotic response systems. Future studies in both humans and humanized mouse models will elucidate the importance of this regulation and lead to the development of potential therapeutic applications