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"Vitamin D-dependent calcium binding proteins were discovered in the cytosolic fractions of chicken intestine, and later in mammalian intestine and kidney, by workers including Robert Wasserman of Cornell University. They bound calcium in the micromolar range and were greatly reduced in vitamin D-deficient animals. Expression could be induced by treating these animals with vitamin D metabolites such as calcitriol. They were found to exist in two distant sizes with a molecular weight of approximately 9 kDa and 28 kDa. They were renamed calbindin; calbindin-D9k is found in mammalian intestine and calbindin-D28k in avain intestine and in kidney."

Vitamin D may not just be good for you, it may help save your life. Recent research from Johns Hopkins University suggests that higher amounts of vitamin D in your diet decreases your likelihood of dying. Studies found that a vitamin D deficiency increases your risk of death by 26 percent, and vitamin D decreases the mortality rate from almost every type of cancer including breast, colon and prostate. Research also suggests that vitamin D helps prevent diabetes, kidney disease and cardiovascular disease.

The vitamin D craze has been building over the last few years, with low levels of the supplement being the blamed as a source of many of our ills. Depression? D can ease it. Chronic pain? Take D. It is said to prevent kidney disease, diabetes, osteoporosis, colon and breast cancer, cardiovascular disease, or even the common cold. Recently, a study linked low vitamin D levels to the rise in Caesarean births.

Age-related changes in the 25-hydroxyvitamin D versus parathyroid hormone relationship suggest a different reason why older adults require more vitamin D. Vieth R, Ladak Y, Walfish PG. J Clin Endocrinol Metab. 2003 Jan;88(1):185-91. PMID: 12519850 This study shows that all age groups exhibit a high prevalence of 25(OH)D insufficiency and secondary hyperparathyroidism. Older adults are just as efficient in maintaining 25(OH)D, but they need more vitamin D to produce the higher 25(OH)D concentrations required to overcome the hyperparathyroidism associated with their diminishing renal function

Vitamin D in preventive medicine: are we ignoring the evidence? Zittermann A. Br J Nutr. 2003 May;89(5):552-72. Review. PMID: 12720576 Vitamin D is metabolised by a hepatic 25-hydroxylase into 25-hydroxyvitamin D (25(OH)D) and by a renal 1alpha-hydroxylase into the vitamin D hormone calcitriol. Calcitriol receptors are present in more than thirty different tissues. Apart from the kidney, several tissues also possess the enzyme 1alpha-hydroxylase, which is able to use circulating 25(OH)D as a substrate. Serum levels of 25(OH)D are the best indicator to assess vitamin D deficiency, insufficiency, hypovitaminosis, adequacy, and toxicity. European children and young adults often have circulating 25(OH)D levels in the insufficiency range during wintertime. Elderly subjects have mean 25(OH)D levels in the insufficiency range throughout the year. In institutionalized subjects 25(OH)D levels are often in the deficiency range. There is now general agreement that a low vitamin D status is involved in the pathogenesis of osteoporosis. Moreover, vitamin D insufficiency can lead to a disturbed muscle function. Epidemiological data also indicate a low vitamin D status in tuberculosis, rheumatoid arthritis, multiple sclerosis, inflammatory bowel diseases, hypertension, and specific types of cancer. Some intervention trials have demonstrated that supplementation with vitamin D or its metabolites is able: (i) to reduce blood pressure in hypertensive patients; (ii) to improve blood glucose levels in diabetics; (iii) to improve symptoms of rheumatoid arthritis and multiple sclerosis. The oral dose necessary to achieve adequate serum 25(OH)D levels is probably much higher than the current recommendations of 5-15 microg/d.

Vitamin D A Key Player In Overall Health Of Several Body Organs, Says Biochemist In a paper published in the August issue of the American Journal of Clinical Nutrition, Norman identifies vitamin D's potential for contributions to good health in the adaptive and innate immune systems, the secretion and regulation of insulin by the pancreas, the heart and blood pressure regulation, muscle strength and brain activity. In addition, access to adequate amounts of vitamin D is believed to be beneficial towards reducing the risk of cancer. Norman also lists 36 organ tissues in the body whose cells respond biologically to vitamin D. The list includes bone marrow, breast, colon, intestine, kidney, lung, prostate, retina, skin, stomach and the uterus.

Tufts University Confirms That Vitamin A Protects Against Vitamin D Toxicity by Curbing Excess Production of Vitamin K-Dependent Proteins Tufts University confirmed my hypothesis that vitamin A protects against vitamin D's induction of renal calcification (kidney stones) by normalizing the production of vitamin K-dependent proteins in December, 2008, without citing my hypothesis or telling me they had confirmed it. I am, of course, very grateful that they thought it significant enough to investigate.

A recent Wall Street Journal article "Defending Against Disease -- With Vitamin D New Studies Suggest It Isn't Just Bones That Might Benefit" by the wonderful Melinda Beck highlights benefits of Vitamin D3. In TYP, we've known the benefits for years :) but it's nice to see the rest of the world catching up. The benefits of Vitamin D3 are potent, powerful immunomodulation -- to the point where autoimmune diseases, viral and bacterial infections and cancer are effectively reduced. What is the value for heart disease and diabetes prevention? In hemodialysis patients, great lessons are can be learned. Nephrologists often describe patients with severe (stage 5) chronic kidney disease (CKD) patients on hemodialysis as having 'hearts of stone, blood vessels of glass.' Unfortunately over 70% of chronic hemodialysis patients have coronary artery disease (and Lp(a)). What medical science shows is that Agatston coronary calcification scores can be dramatically reduced when vitamin D is replenished and calcium is restricted. Sevelamer (Renagel) is a calcium-free, metal-free polymer phosphate binder. In 52-weeks, calcium restriction, a phosphate-binder and vitamin D resulted in one individual in a 21% reduction in Agatston CAC score (from 968 to 756; see Figure 2).

David Feldman, MD, professor of medicine at Stanford, explores the biological action of Vitamin D beyond its widely understood role in the information and maintenance of bone. Emerging therapeutic uses of the vitamin include the prevention and treatment of breast, prostate and colon cancer, chronic kidney disease and arthritis, among other conditions.

"I discussed in my last post how Dr Vieth has a model of tissue 1,25(OH)2D synthesis and degradation in which the level of active substance is pretty well independent of blood vitamin D level, provided the level is either rising or stable. I think it is also worth pointing out that he is talking, hypothetically, about tissue 1,25(OH)2D, not plasma level... As we know, almost nothing is known about tissue 1,25(OH)2D control. By Vieth's hypothesis tissue 1,25(OH)2D is OK so long as there is at least SOME vitamin D present in plasma and the level dose not vary too much. Obviously there is a level below which you can have as much of the enzyme for converting vitamin D to the active form as you like, if there is no vitamin D in your blood you can't make any 1,25(OH)2D in your tissues, or in your kidneys for export to your blood to control calcium levels. At the lower extremes we have rickets and osteomalacia. These are clear cut, unarguable markers of vitamin D deficiency, in the absence of confounding factors (there are a few)."

"Calbindin describes calcium binding proteins first described as the vitamin D-dependent calcium binding proteins in intestine and kidney."

"Vitamin D, often referred to as the "sunshine vitamin," is actually a fat-soluble hormone that the body can synthesize naturally. There are several forms, including two that are important to humans: D2 and D3. Vitamin D2 (ergocalciferol) is synthesized by plants, and vitamin D3 (cholecalciferol) is synthesized by humans when skin is exposed to ultraviolet-B (UVB) rays from sunlight. The active form of the vitamin is calcitriol, synthesized from either D2 or D3 in the kidneys. Vitamin D helps to maintain normal blood levels of calcium and phosphorus"

"Hypovitaminosis D is a deficiency of Vitamin D. It can result from: inadequate intake coupled with inadequate sunlight exposure (in particular sunlight with adequate ultra violet B rays), disorders that limit its absorption, conditions that impair conversion of vitamin D into active metabolites, such as liver or kidney disorders, or, rarely, by a number of hereditary disorders.[1] Deficiency results in impaired bone mineralization, and leads to bone softening diseases, rickets in children and osteomalacia in adults, and contributes to osteoporosis.[1] Osteomalacia may also occur rarely as a side-effect of phenytoin use Hypovitaminosis D is typically diagnosed by measuring the concentration in blood of the compound 25-hydroxyvitamin D (calcidiol), which is a precursor to the active form 1,25-dihydroxyvitamin D (calcitriol).[6] One recent review has proposed the following four categories for hypovitaminosis D:[7] * Insufficient 50-100 nmol/L (20-40 ng/mL) * Mild 25-50 nmol/L (10-20 ng/mL) * Moderate 12.5-25.0 nmol/L (5-10 ng/mL) * Severe < 12.5 nmol/L (< 5 ng/mL) Note that 1.0 nmol/L = 0.4 ng/mL for this compound.[8] Other authors have suggested that a 25-hydroxyvitamin D level of 75-80 nmol/L (30-32 ng/mL) may be sufficient

The relevance of vitamin D receptor (VDR) gene polymorphisms for cancer: a review of the literature. Köstner K, Denzer N, Müller CS, Klein R, Tilgen W, Reichrath J. Anticancer Res. 2009 Sep;29(9):3511-36. Review. PMID: 19667145 CONCLUSION: Significant associations with VDR polymorphisms have been reported in cancer of the breast (Fok1, Bsm1, Taq1, Apa1, poly (A)), prostate (Fok1, Bsm1, Taq1, poly (A)), skin (Fok1, Bsm1, A-1210), colorectum (Fok1, Bsm1), ovary (Fok1, Apa1) and bladder (Fok1), and in renal cell carcinoma (Taq1, Apa1). However, conflicting data have been reported for most malignancies. After careful evaluation of the actual literature, it can be summarized that data indicating an association of VDR polymorphisms and cancer risk are strongest for breast cancer (Bsm1, Fok1), prostate cancer (Fok1) and malignant melanoma (MM) (Fok1). Data indicating an association of VDR polymorphisms and cancer prognosis are strongest for prostate cancer (Fok1), breast cancer (Bsm1, Taq1), MM (Bsm1) and renal cell carcinoma (Taq1).

Fish, vitamin D, and flavonoids in relation to renal cell cancer among smokers. Wilson RT, Wang J, Chinchilli V, Richie JP, Virtamo J, Moore LE, Albanes D. Am J Epidemiol. 2009 Sep 15;170(6):717-29. Epub 2009 Aug 3. PMID: 19651663 doi:10.1093/aje/kwp178 These results suggest that the flavonoid quercetin may prevent renal cell cancer among male smokers. The possible risk associated with fish intake warrants further investigation before conclusions may be drawn.

"Below is a list of summary of actions of Vitamin D (Hormone D)"