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Matti Narkia

The Effect of Vitamin D2 and Vitamin D3 on Intestinal Calcium Absorption in Nigerian Ch... - 0 views

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    The effect of vitamin D2 and vitamin D3 on intestinal calcium absorption in Nigerian children with rickets. Thacher TD, Obadofin MO, O'Brien KO, Abrams SA. J Clin Endocrinol Metab. 2009 Sep;94(9):3314-21. Epub 2009 Jun 30. PMID: 19567516 Conclusions: Despite similar increases in 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D with vitamin D2 or vitamin D3, fractional calcium absorption did not increase, indicating that rickets in Nigerian children is not primarily due to vitamin D-deficient calcium malabsorption
Matti Narkia

Acid-base balance and bone - Acid-base balance, dentinogenesis and dental caries: Exper... - 0 views

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    Acid-base balance has an effect on bone turnover, especially on the rates of bone resorption and calcium mobilization. Bone mineral participates in the defense against acid-base disturbances, especially against metabolic acidosis (Lemann et al. 1966, Green & Kleeman 1991). The role of the bone mineral is important in the acid-base disorders, as no appreciable change in the intestinal calcium absorption occurs (Bichara et al. 1990). In the mammalian body, mainly three hormones regulate the calcium metabolism and the bone turnover. 1,25-dihydroxycholecalciferol (vitamin D derivative) increases calcium absorption from the intestine and, indirectly, from bone. Parathyroid hormone mobilizes calcium from the bone and increases the urinary phosphate excretion. Calcitonin inhibits bone resorption (Ganong 1981). Used as drugs, these hormones are also capable of inducing acid-base disorders. Calcitonin administration (Escanero et al. 1991) and vitamin D excess (Bichara et al. 1990) have been reported to cause metabolic alkalosis.
Matti Narkia

Calcium absorption varies within the reference range for serum 25-hydroxyvitamin D. - ... - 0 views

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    Calcium absorption varies within the reference range for serum 25-hydroxyvitamin D. Heaney RP, Dowell MS, Hale CA, Bendich A. J Am Coll Nutr. 2003 Apr;22(2):142-6. PMID: 12672710
Matti Narkia

Effects of Above Average Summer Sun Exposure on Serum 25-Hydroxyvitamin D and Calcium A... - 0 views

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    Barger-Lux MJ, Heaney RP. Effects of above average summer sun exposure on serum 25-hydroxyvitamin D and calcium absorption.J Clin Endocrinol Metab. 2002 Nov;87(11):4952-6.PMID: 12414856 [PubMed - indexed for MEDLINE]
Matti Narkia

Plasma Vitamin D and 25OHD Responses of Young and Old Men to Supplementation with Vitam... - 0 views

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    Plasma vitamin D and 25OHD responses of young and old men to supplementation with vitamin D3. Harris SS, Dawson-Hughes B. J Am Coll Nutr. 2002 Aug;21(4):357-62. PMID: 12166534 Conclusions: There appears to be no age-related impairment among men in the absorption or metabolism of 20 µg/day of vitamin D3 taken orally for at least eight weeks.
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

Not enough vitamin D: Health consequences for Canadians -- Schwalfenberg 53 (5): 841 --... - 0 views

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    Not enough vitamin D: health consequences for Canadians. Schwalfenberg G. Can Fam Physician. 2007 May;53(5):841-54. Review PMID: 17872747 Conclusion Low levels of VTD are considered a major public health problem in Canada, especially during the winter. Those with risk factors should be screened for low 25(OH)D levels and repletion therapy instituted if needed. Researchers have estimated that the oral dose of vitamin D3 to attain and maintain 25(OH)D levels >80 nmol/L is 2200 IU/d if baseline levels are 20 to 40 nmol/L, 1800 IU/d if levels are 40 to 60 nmol/L, and 1160 IU/d if levels are between 60 and 80 nmol/L.64 We need to ensure that patients have healthy blood levels of 25(OH)D to prevent levels of parathyroid hormone from rising and to maximize absorption of calcium, magnesium, and phosphate. Positive effects on bone are marginal at best unless patients consume at least 800 IU/d of VTD. The emerging and exciting role of the VTD receptor and the actions of VTD in maintaining health in other cell types have become more apparent during the last decade.
Matti Narkia

Vitamin D requirements: current and future -- Weaver and Fleet 80 (6): 1735S -- America... - 0 views

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    Upper levels of vitamin D intake were set at 50 microg/d (2000 IU/d) for all ages. Some individuals would require higher levels than these to achieve serum 25-hydroxyvitamin D concentrations for optimal calcium absorption. So much new information on vitamin D and health has been collected since the requirements were set in 1997 that this nutrient is likely the most in need of revised requirements. Vitamin D requirements: current and future. Weaver CM, Fleet JC. Am J Clin Nutr. 2004 Dec;80(6 Suppl):1735S-9S. Review. Erratum in: Am J Clin Nutr. 2005 Mar;81(3):729. PMID: 15585797
Matti Narkia

Vitamin D deficiency is the cause of common obesity - 0 views

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    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 Common obesity and the metabolic syndrome may therefore result from an anomalous adaptive winter response. The stimulus for the winter response is proposed to be a fall in vitamin D. The synthesis of vitamin D is dependent upon the absorption of radiation in the ultraviolet-B range of sunlight. At ground level at mid-latitudes, UV-B radiation falls in the autumn and becomes negligible in winter. It has previously been proposed that vitamin D evolved in primitive organisms as a UV-B sensitive photoreceptor with the function of signaling changes in sunlight intensity. It is here proposed that a fall in vitamin D in the form of circulating calcidiol is the stimulus for the winter response, which consists of an accumulation of fat mass (obesity) and the induction of a winter metabolism (the metabolic syndrome). Vitamin D deficiency can account for the secular trends in the prevalence of obesity and for individual differences in its onset and severity. It may be possible to reverse the increasing prevalence of obesity by improving vitamin D status.
Matti Narkia

New topics in vitamin D research - Google Books - 2 views

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    Table of Contents Ch. I Is calcidiol an active hormone? 1 Ch. II Vitamin D as a neurosteroid hormone : from neurobiological effects to behavior 29 Ch. III Inhibitors of vitamin D hydroxylases : mechanistic tools and therapeutic aspects 67 Ch. IV Vitamin D analogues as anti-cancer therapies 145 Ch. V Paricalcitol : a vitamin D2 analog with anticancer effects with low calcemic activity 169 Ch. VI Vitamin D use among older adults in U.S. : results form national surveys 1997 to 2002 181 Ch VII Vitamin D deficiency in migrants 199 Vitamin D is a fat-soluble steroid hormone precursor that contributes to the maintenance of normal levels of calcium and phosphorus in the bloodstream. Strictly speaking, it is not a vitamin since human skin can manufacture it, but it is referred to as one for historical reasons. It is often known as calciferol. The major biologic function of vitamin D is to maintain normal blood levels of calcium and phosphorus. Vitamin D aids in the absorption of calcium, helping to form and maintain strong bones. It promotes bone mineralisation in concert with a number of other vitamins, minerals and hormones. Without vitamin D, bones can become thin, brittle, soft or misshapen. Vitamin D prevents rickets in children and osteomalacia in adults -- skeletal diseases that result in defects that weaken bones. This book gathers international research on the leading-edge of the scientific front.
Matti Narkia

VitaminD3 - Ted Hutchinson's blog - 0 views

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    "Thursday, 17 December 2009 This blog is in response to Dr Briffa's post here. as I keep having problems commenting on his blogs. While 44ng/ml is sufficient to not only maximize uptake of calcium (>32ng/ml) and ensure maximum bone mineral density (>42ng/ml), pregnant and nursing mothers should be aware that in order to maximize the amount of vitamin D3 in human breast milk 6400iu/daily was found to be necessary to raise (>58ng/ml) at latitude 32. This is detailed in the Taylor, Wagner and Hollis paper. Vitamin D supplementation during lactation to support infant and mother. Although 4000iu/daily met the mothers daily needs in full it left babies being born with lower 25(OH)D status than required for optimum calcium absorption They also found DAILY use of supplements was required by pregnant and nursing mothers to ensure an even daily Vitamin D3 supply to the foetus & baby. It makes virtually no measurable difference for everyone else if you supplement daily or weekly. While Dr Briffa will not be lactating he may be interested seeing in the Grassrootshealth chart showing disease incidence by 25(OH)D status. this may encourage him to go just another 10ng/ml higher and a bit nearer to the natural level at which human breast milk flows replete with D3."
Matti Narkia

Hypovitaminosis D - Wikipedia, the free encyclopedia - 0 views

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    "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
Matti Narkia

Functional indices of vitamin D status and ramifications of vitamin D deficiency -- Hea... - 0 views

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    Heaney RP. Functional indices of vitamin D status and ramifications of vitamin D deficiency.Am J Clin Nutr. 2004 Dec;80(6 Suppl):1706S-9S. Review.PMID: 15585791 [PubMed - indexed for MEDLINE]
Matti Narkia

The Bioavailability of Vitamin D from Fortified Cheeses and Supplements Is Equivalent i... - 0 views

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    The bioavailability of vitamin D from fortified cheeses and supplements is equivalent in adults. Wagner D, Sidhom G, Whiting SJ, Rousseau D, Vieth R. J Nutr. 2008 Jul;138(7):1365-71. PMID: 18567762 Compared with baseline, serum parathyroid hormone decreased with both fortification (P = 0.003) and supplementation (P = 0.012). These data demonstrate that vitamin D is equally bioavailable from fortified hard cheeses and supplements, making cheese suitable for vitamin D fortification.
Matti Narkia

Bread Fortified with Cholecalciferol Increases the Serum 25-Hydroxyvitamin D Concentrat... - 0 views

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    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.
Matti Narkia

A randomised comparison of increase in serum 25-hydroxyvitamin D concentratio... - 0 views

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    A randomised comparison of increase in serum 25-hydroxyvitamin D concentration after 4 weeks of daily oral intake of 10 microg cholecalciferol from multivitamin tablets or fish oil capsules in healthy young adults. Holvik K, Madar AA, Meyer HE, Lofthus CM, Stene LC. Br J Nutr. 2007 Sep;98(3):620-5. Epub 2007 Apr 24. PMID: 17456248 We conclude that fish oil capsules and multivitamin tablets containing 10 microg cholecalciferol administered over a 4-week period produced a similar mean increase in s-25(OH)D concentration.
adrenalfatigueus

Adrenal Fatigue Supplements - Liposomal Delivery | Adrenal Fatigue Solution - 1 views

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    Working towards total health is an important, conscious effort to be made every day. All of our products ensure maximum nutrient absorption on a cellular level. The desire to decrease stress and increase individual cell function in health-conscious people is at the heart of every product.
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