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Effectiveness and safety of vitamin D in relation to bone health. Cranney A, Horsley T, O'Donnell S, Weiler H, Puil L, Ooi D, Atkinson S, Ward L, Moher D, Hanley D, Fang M, Yazdi F, Garritty C, Sampson M, Barrowman N, Tsertsvadze A, Mamaladze V. Evid Rep Technol Assess (Full Rep). 2007 Aug;(158):1-235. Review. PMID: 18088161 CONCLUSIONS: The results highlight the need for additional high quality studies in infants, children, premenopausal women, and diverse racial or ethnic groups. There was fair evidence from studies of an association between circulating 25(OH)D concentrations with some bone health outcomes (established rickets, PTH, falls, BMD). However, the evidence for an association was inconsistent for other outcomes (e.g., BMC in infants and fractures in adults). It was difficult to define specific thresholds of circulating 25(OH)D for optimal bone health due to the imprecision of different 25(OH)D assays. Standard reference preparations are needed so that serum 25(OH)D can be accurately and reliably measured, and validated. In most trials, the effects of vitamin D and calcium could not be separated. Vitamin D(3) (>700 IU/day) with calcium supplementation compared to placebo has a small beneficial effect on BMD, and reduces the risk of fractures and falls although benefit may be confined to specific subgroups. Vitamin D intake above current dietary reference intakes was not reported to be associated with an increased risk of adverse events. However, most trials of higher doses of vitamin D were not adequately designed to assess long-term harms.

Effectiveness and safety of vitamin D in relation to bone health. Cranney A, Horsley T, O'Donnell S, Weiler H, Puil L, Ooi D, Atkinson S, Ward L, Moher D, Hanley D, Fang M, Yazdi F, Garritty C, Sampson M, Barrowman N, Tsertsvadze A, Mamaladze V. Evid Rep Technol Assess (Full Rep). 2007 Aug;(158):1-235. Review. PMID: 18088161 CONCLUSIONS: The results highlight the need for additional high quality studies in infants, children, premenopausal women, and diverse racial or ethnic groups. There was fair evidence from studies of an association between circulating 25(OH)D concentrations with some bone health outcomes (established rickets, PTH, falls, BMD). However, the evidence for an association was inconsistent for other outcomes (e.g., BMC in infants and fractures in adults). It was difficult to define specific thresholds of circulating 25(OH)D for optimal bone health due to the imprecision of different 25(OH)D assays. Standard reference preparations are needed so that serum 25(OH)D can be accurately and reliably measured, and validated. In most trials, the effects of vitamin D and calcium could not be separated. Vitamin D(3) (>700 IU/day) with calcium supplementation compared to placebo has a small beneficial effect on BMD, and reduces the risk of fractures and falls although benefit may be confined to specific subgroups. Vitamin D intake above current dietary reference intakes was not reported to be associated with an increased risk of adverse events. However, most trials of higher doses of vitamin D were not adequately designed to assess long-term harms.

Summary of evidence-based review on vitamin D efficacy and safety in relation to bone health. Cranney A, Weiler HA, O'Donnell S, Puil L. Am J Clin Nutr. 2008 Aug;88(2):513S-519S. Review. PMID: 18689393 We found inconsistent evidence of an association between serum 25-hydroxyvitamin D [25(OH)D] concentration and bone mineral content in infants and fair evidence of an association with bone mineral content or density in older children and older adults. The evidence of an association between serum 25(OH)D concentration and some clinical outcomes (fractures, performance measures) in postmenopausal women and older men was inconsistent, and the evidence of an association with falls was fair. We found good evidence of a positive effect of consuming vitamin D-fortified foods on 25(OH)D concentrations. The evidence for a benefit of vitamin D on falls and fractures varied. We found fair evidence that adults tolerated vitamin D at doses above current dietary reference intake levels, but we had no data on the association between long-term harms and higher doses of vitamin D.

Healthy elderly French women living at home have secondary hyperparathyroidism and high bone turnover in winter. EPIDOS Study Group. Chapuy MC, Schott AM, Garnero P, Hans D, Delmas PD, Meunier PJ. J Clin Endocrinol Metab. 1996 Mar;81(3):1129-33. PMID: 8772587 These results show that vitamin D status of a French aged population in good health and living at home depends mainly on lifestyle. Like institutionalized women, old women living at home exhibit clear evidence of senile hyperparathyroidism in the winter, secondary in part to a reduced 25OHD level and associated with biological signs of increased bone turnover. The maintenance of PTH within the normal range for healthy adults by vitamin D and calcium treatment might constitute an approach for the prevention of bone loss in the entire

Vitamin D deficiency and bone health in healthy adults in Finland: could this be a concern in other parts of Europe? Lamberg-Allardt CJ, Outila TA, Kärkkainen MU, Rita HJ, Valsta LM. J Bone Miner Res. 2001 Nov;16(11):2066-73. PMID: 11697803 Low vitamin D status was prevalent in these young adults in northern Europe in winter, although the vitamin D intake met the recommendation. This probably is not a local problem for northern Europe, because the natural sources of vitamin D are scarce and fortification is not very common in Europe, and with the exception of the southern part of Europe, sunshine is not very abundant in this part of the world. Thus, the results of this study indicate that more attention should be focused on vitamin D status and the sources of vitamin D in these countries.

Strong correlations have been noted between cardiovascular diseases and low bone density / osteoporosis-connections so strong that the presence of one is considered a likely predictor of the other. This relationship has led to the hypothesis that these conditions share core pathophysiological mechanisms. Recent advances in our understanding of the complimentary roles played by vitamin D3 and vitamin K2 in vascular and bone health provide support for this hypothesis, along with insight into key metabolic dysfunctions underlying cardiovascular disease and osteoporosis. Part II, The Vitamin K Connection to Cardiovascular Health, reviews the ways in which vitamin K regulates calcium utlization, preventing vascular and soft tissue calcification while complimenting the bone-building actions of vitamin D, and also discusses vitamin K safety and dosage issues, and the necessity of providing vitamin K and vitamin A along with vitamin D to preclude adverse effects associated with hypervitaminosis D.

Vitamin D status affects serum parathyroid hormone concentrations during winter in female adolescents: associations with forearm bone mineral density. Outila TA, Kärkkäinen MU, Lamberg-Allardt CJ. Am J Clin Nutr. 2001 Aug;74(2):206-10. PMID: 11470722 Conclusion: A large percentage of adolescent females have low vitamin D status during the winter in Finland, which seems to have negative effects on bone health.

Defining Adequate Vitamin D Intake : Cross-sectional and Intervention Studies Viljakainen, Heli Tuulikki University of Helsinki 2008-05-23 Doctoral dissertation (article-based) Vitamin D is required for normal bone growth and maintenance of the skeleton throughout life. In Finland, like in many other Western countries, the population suffers from inadequate or deficient vitamin D status, especially during winter, which is thought to increase the risk of osteoporosis. New strategies to prevent osteoporosis are actively being sought. The main objective of this thesis was to determine whether vitamin D is feasible in the primary prevention of osteoporosis; does it affect bone mineral accrual during the growth period? A second goal was to ascertain whether seasonal variation in calcitropic hormones affects bone remodelling, and to elucidate the vitamin D intake needed to overcome this variation in different age groups. In summary, vitamin D intake remains inadequate among the target groups of this thesis, as reflected by seasonal variation in calcitropic hormones and bone metabolism. Dietary intake of vitamin D should be increased to achieve at least an adequate vitamin D status (S-25-OHD>50 nmol/l) and possibly an optimal vitamin D status (S-25-OHD>80 nmol/l) throughout the year. This could be accomplished by introducing new vitamin D-fortified foods to the market."

Dairy and bone health. Heaney RP. J Am Coll Nutr. 2009 Feb;28 Suppl 1:82S-90S. PMID: 19571166

Effectiveness and safety of vitamin D in relation to bone health. Cranney A, Horsley T, O'Donnell S, Weiler H, Puil L, Ooi D, Atkinson S, Ward L, Moher D, Hanley D, Fang M, Yazdi F, Garritty C, Sampson M, Barrowman N, Tsertsvadze A, Mamaladze V. Evid Rep Technol Assess (Full Rep). 2007 Aug;(158):1-235. Review. PMID: 18088161

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.

Optimal serum 25-hydroxyvitamin D levels for multiple health outcomes. Bischoff-Ferrari HA. Adv Exp Med Biol. 2008;624:55-71. Review. PMID: 18348447 DOI: 10.1007/978-0-387-77574-6_5 Recent evidence suggests that higher vitamin D intakes beyond current recommendations may be associated with better health outcomes. In this chapter, evidence is summarized from different studies that evaluate threshold levels for serum 25(OH)D levels in relation to bone mineral density (BMD), lower extremity function, dental health, risk of falls, admission to nursing home, fractures, cancer prevention and incident hypertension. For all endpoints, the most advantageous serum levels for 25(OH)D appeared to be at least 75 nmol/l (30 ng/ml) and for cancer prevention, desirable 25(OH)D levels are between 90-120 nmol/l (36-48 ng/ml). An intake of no less than 1000IU (25 meg) of vitamin D3 (cholecalciferol) per day for all adults may bring at least 50% of the population up to 75 nmol/l. Thus, higher doses of vitamin D are needed to bring most individuals into the desired range. While estimates suggest that 2000 IU vitamin D3 per day may successfully and safely achieve this goal, the implications of 2000 IU or higher doses for the total adult population need to be addressed in future studies.

Holick MF. Sunlight and vitamin D for bone health and prevention of autoimmune diseases, cancers, and cardiovascular disease. Am J Clin Nutr. 2004 Dec;80(6 Suppl):1678S-88S. Review. PMID: 15585788 [PubMed - indexed for MEDLINE]

"People with coeliac disease may be more susceptible to osteoporosis because their own immune system attacks their bone tissue, a study suggests. Osteoporosis is a known risk of coeliac disease and has been explained by a failure to absorb calcium or vitamin 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.

In his recent essay, Trevor G. Marshall explores how vitamin D supplementation may be contributing to the current epidemics of obesity and chronic disease[1]. Unfortunately, he has overlooked many important papers that disagree with his hypothesis. This letter points out some of the omissions. The health benefits of vitamin D3 have been reviewed recently[2]. The benefits for bone health have been known for nearly a century. Benefits for cancer, infectious diseases, autoimmune diseases, and metabolic diseases have been identified in the past three decades.

Strong correlations have been noted between cardiovascular diseases and low bone density / osteoporosis-connections so strong that the presence of one type of pathology is considered a likely predictor of the other. This potentially causal relationship has led to the hypothesis that these conditions share core mechanisms. Recent advances in our understanding of the complimentary roles played by vitamin D3 and vitamin K2 in vascular and bone health provide support for this hypothesis, along with insight into key metabolic dysfunctions underlying cardiovascular disease and osteoporosis. Part I of this review summarizes current research linking vitamin D deficiency to cardiovascular disease, the physiological mechanisms underlying vitamin D's cardiovascular effects, and leading vitamin D researchers' recommendations for significantly higher supplemental doses of the pro-hormone. Part II reviews the vitamin K connection to cardiovascular disease; the ways in which vitamin D and vitamin K pair up to prevent inflammation, vascular calcification and osteoporosis; and the necessity of providing vitamin K along with vitamin D to preclude adverse effects associated with hypervitaminosis D, which include vascular and other soft tissue calcification.

Vitamin D and skin physiology: a D-lightful story. Holick MF, Chen TC, Lu Z, Sauter E. J Bone Miner Res. 2007 Dec;22 Suppl 2:V28-33. PMID: 18290718 doi: 10.1359/jbmr.07s211 Very few foods naturally contain vitamin D, and those that do have a very variable vitamin D content. Recently it was observed that wild caught salmon had between 75% and 90% more vitamin D(3) compared with farmed salmon. The associations regarding increased risk of common deadly cancers, autoimmune diseases, infectious diseases, and cardiovascular disease with living at higher latitudes and being prone to vitamin D deficiency should alert all health care professionals about the importance of vitamin D for overall health and well being. Humans have depended on sunlight for their vitamin D requirement. The impact of season, time of day, and latitude on vitamin D synthesis is well documented.(2,3) We now report that altitude also has a dramatic influence on vitamin D3 production and that living at altitudes above 3500 m permits previtamin D3 production at a time when very little is produced at latitudes below 3400 m. It was surprising that, at 27° N in Agra (169 M), little previtamin D3 production was observed. However, there was significant air pollution that caused a haze over the city. It is likely the ozone and other UVB-absorbing pollutants in the air prevented the solar UVB photons from reaching the earth's surface to produce previtamin D3.

"NEW YORK (Reuters Health) - Important news for seniors: A daily dose of vitamin D cuts your risk of falling substantially, researchers reported today. But not just any dose will do. "It takes 700 to 1000 international units (IU) of vitamin D per day and nothing less will work," Dr. Heike A. Bischoff-Ferrari, who directs the Center on Aging and Mobility at the University of Zurich, Switzerland, noted in an email to Reuters Health. Those recommendations - which are higher than those by the U.S. Institute of Medicine -- are based on the results of eight studies that looked at vitamin D supplements for fall prevention among more than 2,400 adults aged 65 and older. Falls were not notably reduced with daily doses of vitamin D lower than 700 IU. An analysis of all eight studies, posted online today in the British Medical Journal, add weight to several others which have shown that vitamin D improves strength and balance, and bone health in the elderly, the researchers note."

Vitamin D: It's Not Just For Bones Anymore. A presentation professor David Feldman