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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

"Vitamin D may be more important to colon cancer prevention than previously believed, according to a study published in the Journal of the American Medical Association (Vol. 290, No. 22: 2959-2967). The study examined people with no symptoms of colon cancer to determine what role diet, exercise, smoking, and other behaviors played in the development or not of colon polyps, small growths in the colon that can turn into cancer if they aren't removed."

The vitamin D-antimicrobial peptide pathway and its role in protection against infection. Gombart AF. Future Microbiol. 2009 Nov;4:1151-65. PMID: 19895218 doi:10.2217/fmb.09.87

Nutrition recuperation can improve your life. Nutrition recuperation plays a key role in all aspects of your life.

The Linus Pauling Institute's Micronutrient Information Center is a source for scientifically accurate information regarding the roles of vitamins, minerals, other nutrients, dietary phytochemicals (plant chemicals that may affect health), and some foods

Dietary recommendations for vitamin D: a critical need for functional end points to establish an estimated average requirement. Whiting SJ, Calvo MS. J Nutr. 2005 Feb;135(2):304-9. Review. PMID: 15671232 In summary, vitamin D has emerged as a critical nutrient for which there is a compelling health need to establish adequate dietary guidelines in North America and worldwide given the increasing evidence of vitamin D deficiency and insufficient links to risk of chronic disease. We strongly argue that now there are enough data to consider setting an estimated average requirement for vitamin D and to recognize the crucial need for more research to determine the role of vitamin D in noncalciotropic functions and prevention of chronic diseases

Vitamin D status and glucose homeostasis in the 1958 British birth cohort: the role of obesity. Hyppönen E, Power C. Diabetes Care. 2006 Oct;29(10):2244-6. PMID: 17003300 doi: 10.2337/dc06-0946 CONCLUSIONS-Body size was a strong determinant for 25(OH)D, with concentrations being suboptimal in most obese participants. Randomized controlled trials [using dosages sufficient to improve 25(OH)D also for the obese] are required to determine whether clinically relevant improvements in glucose metabolism can be obtained by vitamin D supplementation.

Hypovitaminosis D in British adults at age 45 y: nationwide cohort study of dietary and lifestyle predictors. Hyppönen E, Power C. Am J Clin Nutr. 2007 Mar;85(3):860-8. PMID: 17344510 Conclusion: Prevalence of hypovitaminosis D in the general population was alarmingly high during the winter and spring, which warrants action at a population level rather than at a risk group level. Data from the 1958 birth cohort suggest that, at different cutoffs for hypovitaminosis D, a substantial public health problem exists in British whites. Obese participants and those living in Scotland were at the highest risk of hypovitaminosis D. However, the prevalence in the general population was very high during the winter and spring, which suggests that, to improve the situation, action is required at a population level rather than at a risk-group level. In the United States, calls have gone out for an increase in vitamin D fortification of foods (11), and the data from the current study suggest that such action is also warranted in the United Kingdom. Vitamin D is currently available without prescription as a dietary supplement only as part of cod liver oil or multivitamin products; hence, a need clearly exists to consider increased availability of over-the-counter supplements. Hypovitaminosis D has been implicated in the development of serious conditions, including diabetes, various types of cancer, and cardiovascular diseases, in addition to its essential role in maintaining bone health (1, 2). The high rates of hypovitaminosis D reported in this study suggest that immediate action is needed to improve the vitamin D status of the British population.

Stress fractures in the Israeli defense forces from 1995 to 1996. Givon U, Friedman E, Reiner A, Vered I, Finestone A, Shemer J. Clin Orthop Relat Res. 2000 Apr;(373):227-32. PMID: 10810481 Serum levels of bone specific alkaline phosphatase and osteocalcin were elevated in patients with high grade stress fractures compared with control subjects with no symptoms: 37.6 versus 26.2 units/L, and 10.8 versus 8.8 ng/mL, respectively. Levels of 25-hydroxy vitamin D were lower in patients with high grade stress fractures (25.3 ng/mL) than in control subjects (29.8 ng/mL). This study revealed that several parameters can distinguish soldiers with high grade stress fractures, but their predictive value and precise pathogenetic role remain unclear.

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.

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.

A new study by researchers at the University of Colorado Denver and Massachusetts General Hospital (MGH) shows vitamin D plays a vital role in reducing the risk of death associated with older age. The research, just published in the Journal of the American Geriatrics Society, evaluated the association between vitamin D levels in the blood and the death rates of those 65 and older. The study found that older adults with insufficient levels of vitamin D die from heart disease at greater rates that those with adequate levels of the vitamin.

A longitudinal study of serum 25-hydroxyvitamin D and intact parathyroid hormone levels indicate the importance of vitamin D and calcium homeostasis regulation in multiple sclerosis. Soilu-Hänninen M, Laaksonen M, Laitinen I, Erälinna JP, Lilius EM, Mononen I. J Neurol Neurosurg Psychiatry. 2008 Feb;79(2):152-7. Epub 2007 Jun 19. PMID: 17578859 doi:10.1136/jnnp.2006.105320 Conclusions: The endocrine circuitry regulating serum calcium may be altered in MS. There is an inverse relationship between serum vitamin D level and MS clinical activity. The role of vitamin D in MS must be explored further.

This DRI report presents calcium, phosphorus, magnesium, vitamin D, and fluoride, all of which have key roles in developing and maintaining bone and other calcified tissues in the body. View or download the entire 454 page document or just selected sections below, or find information for obtaining the book version. Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride (1997) National Academy of Sciences. Institute of Medicine. Food and Nutrition Board.

Vitamin D plays a critical role in the human body's response to tuberculosis, according to new research that explains why people of African descent are more susceptible to TB. The research also suggests a new way to fight one of the world's deadliest diseases: with a simple dietary supplement. Tuberculosis, usually caused when a person inhales tuberculosis bacteria, killed an estimated 1.7 million people in 2003 and is the leading cause of death for people afflicted with AIDS, according to the World Health Organization (WHO).

Conclusion The data point to a critical role for the VDR and 1,25(OH)2D3 in control of innate immunity and the response of the colon to chemical injury. Vitamin D and the vitamin D receptor are critical for control of the innate immune response to colonic injury. Froicu M, Cantorna MT. BMC Immunol. 2007 Mar 30;8:5. PMID: 17397543 doi:10.1186/1471-2172-8-5

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

Ecological studies of ultraviolet B, vitamin D and cancer since 2000. Grant WB, Mohr SB. Ann Epidemiol. 2009 Jul;19(7):446-54. Epub 2009 Mar 9. PMID: 19269856 CONCLUSION: These findings provide strong evidence that vitamin D status plays an important role in controlling the outcome of cancer. Support for the UVB-vitamin D-cancer theory is now scientifically strong enough to warrant use of vitamin D in cancer prevention, and as a component of treatment. More research studies would help to explore whether there are benefits beyond the substantial effects that have been observed.

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.

Our results of an association with the Fok1 VDR polymorphism further support a role of the vitamin D pathway in ovarian carcinogenesis. Polymorphisms in the vitamin D receptor and risk of ovarian cancer in four studies. Tworoger SS, Gates MA, Lee IM, Buring JE, Titus-Ernstoff L, Cramer D, Hankinson SE. Cancer Res. 2009 Mar 1;69(5):1885-91. Epub 2009 Feb 17. Erratum in: Cancer Res. 2009 Jun 15;69(12):5267. Gate, Margaret A [corrected to Gates, Margaret A]. PMID: 19223536 doi: 10.1158/0008-5472.CAN-08-3515