Vitamin D deficiency: A global perspective.

Bandeira F

,

Griz L

,

Dreyer P

,

Eufrazino C

,

Bandeira C

,

Freese E

.

Vitamin D is essential for the maintenance of good health. Its sources can be skin production and diet intake. Most humans depend on sunlight exposure (UVB 290-315 nm) to satisfy their requirements for vitamin D. Solar ultraviolet B photons are absorbed by the skin, leading to transformation of 7 dehydrocholesterol into vitamin D3 (cholecalciferol). Season, latitude, time of day, skin pigmentation, aging, sunscreen use, all influence the cutaneous production of vitamin D3. Vitamin D deficiency not only causes rickets among children but also precipitates and exacerbates osteoporosis among adults and causes the painful bone disease osteomalacia.

Vitamin D deficiency has been associated with increased risk for other morbidities such as cardiovascular disease, type 1 and type 2 diabetes mellitus and cancer, especially of the colon and prostate

. The prevalence of hypovitaminosis D is considerable even in low latitudes and should be taken into account in the evaluation of postmenopausal and male osteoporosis. Although severe vitamin D deficiency leading to rickets or osteomalacia is rare in Brazil, there is accumulating evidence of the frequent occurrence of subclinical vitamin D deficiency, especially in elderly people.

Curr Med Res Opin.

2007 Nov 21

Molecular basis of the potential of vitamin D to prevent cancer.

Ingraham BA , Bragdon B , Nohe A .

OBJECTIVE: To review current research findings in cell biology, epidemiology, preclinical, and clinical trials on the protective effects of vitamin D against the development of cancers of the breast, colon, prostate, lung, and ovary. Current recommendations for optimal vitamin D status, the movement towards revision of standards, and reflections on healthy exposure to sunlight are also reviewed.Search methodology: A literature search was conducted in April and updated in September 2007. The Medline and Web of Knowledge databases were searched for primary and review articles published between 1970 and 2007, using the search terms vitamin D, calcitriol, cancer, chemoprevention, nuclear receptor, vitamin D receptor, apoptosis, cell cycle, epidemiology, and cell adhesion molecule. Articles that focused on epidemiological, preclinical, and clinical evidence for vitamin Ds effects were selected and additional articles were obtained from reference lists of the retrieved articles.FINDINGS: An increasing body of research supports the hypothesis that the active form of vitamin D has significant, protective effects against the development of cancer. Epidemiological studies show an inverse association between sun exposure, serum levels of 25(OH)D, and intakes of vitamin D and risk of developing and/or surviving cancer. The protective effects of vitamin D result from its role as a nuclear transcription factor that regulates cell growth, differentiation, apoptosis and a wide range of cellular mechanisms central to the development of cancer. A significant number of individuals have serum vitamin D levels lower than what appears to protect against cancer, and the research community is currently revising the guidelines for optimal health. This will lead to improved public health policies and to reduced risk of cancer.CONCLUSIONS:

Research strongly supports the view that efforts to improve vitamin D status would have significant protective effects against the development of cancer

. The clinical research community is currently revising recommendations for optimal serum levels and for sensible levels of sun exposure, to levels greater than previously thought. Currently, most experts in the field believe that intakes of between 1000 and 4000 IU will lead to a more healthy level of serum 25(OH)D, in the range of 75 nmol/L that will offer significant protect effects against cancers of the breast, colon, prostate, ovary, lungs, and pancreas. The first randomized trial has shown significant protection against breast cancer, and other clinical trials will follow and ultimately lead to improved public health policies and significantly fewer cancers.

J Nutr.

2007 Nov;137(11 Suppl):2576S-2579S. Related Articles , Links /entrez/utils/fref.fcgi?PrId=3051&itool=Abstract def&uid=17951506&db=pubmed&url=http://jn.nutrition.org/cgi/pmidlookup?view=long&pmid=17951506/entrez/utils/fref.fcgi?PrId=305 1&itool=Abstract-def&uid=17951506&db=pubmed&url=http://jn.nutrition.org/cgi/pmidlookup?view=long&pmid=17951506

Dietary modulation of colon cancer risk.

Kim YS , Milner JA .

Nutritional Science Research Group, Division of Cancer Prevention, National Cancer Institute, Bethesda, MD 20892, USA. [email protected]

Colon cancer remains a significant global health concern. The impact of specific dietary components on colon tissue likely depends on a host of genomic processes that influence the growth, development, and differentiation of the epithelial cells at the colon crypt surface, where the balance between proliferation and differentiation is maintained possibly through the Wnt (beta-catenin/T-cell factor) signaling pathway. A loss of balance caused by either genetic mutations or environmental factors such as dietary habits can modulate the risk for the formation of aberrant crypt foci and ultimately the development of colon cancer. Evidence exists that butyrate reduces the number and the size of aberrant crypt foci in the colon. Butyrate is a natural histone deacetylase inhibitor as well as a molecule involved with enhanced TGF-beta-induced SMAD3 phosphorylation, increased IFN-gamma-mediated apoptosis, and altered expression of the intestinal muc2 gene that is responsible for mucin synthesis. Other dietary components, such as vitamin D and (n-3) fatty acids, may regulate proliferative properties of colon progenitor cells as well as the differentiation of subcellular lineages. Although these findings are intriguing, there are uncertainties that remain to be resolved including the optimal exposure needed to bring about an effect, the appropriate timing of administration, and if nutrient-nutrient and nutrient-gene interactions determine the overall response. The expanded use of high-throughput technologies, knowledge about the expression of genes and protein fingerprints, and metabolomic profiling will assist in addressing these issues and ultimately in determining the physiological significance of bioactive food components as cancer protectants.

Dermatol Clin.

2007 Oct;25(4):515-23, viii. Related Articles , Links /entrez/utils/fref.fcgi?PrId=3048&itool=Abstract def&uid=17903610&db=pubmed&url=http://linkinghub.elsevier.com/retrieve/pii/S0733-8635(07)00062 9/entrez/utils/fref.fcgi?PrId=3048&itool=Abstract def&uid=17903610&db=pubmed&url=http://linkinghub.elsevier.com/retrieve/pii/S0733-8635(07)00062-9

The vitamin D receptor.

Carlberg C , Seuter S .

Life Sciences Research Unit, Universitè of Luxembourg, 162A, Avenue de la Faïencerie, L-1511 Luxembourg, Luxembourg. [email protected]

The vitamin D endocrine system is known for its essential role in calcium homeostasis and bone metabolism, and induces cell differentiation, inhibits cell growth, controls other hormonal systems, and modulates the immune response. Vitamin D(3) is a prohormone that is taken up by diet or synthesized in ultraviolet radiation-exposed skin and metabolically converted to the active metabolite, 1alpha,25-dihydroxyvitamin D(3). This nuclear hormone binds with high affinity the nuclear receptor vitamin D receptor. More than 3000 synthetic analogs of 1alpha,25(OH)(2)D(3) are known. This review aims to provide an overview on vitamin D signaling from the skin perspective.

Acta Med Indones.

2007 Jul-Sep;39(3):133-41. Related Articles , Links

Vitamin D and autoimmune disease.

Ginanjar E , Sumariyono , Setiati S , Setiyohadi B .

Department of Internal Medicine, Faculty of Medicine, University of Indonesia, dr. Cipto Mangunkusumo Hospital, Jakarta.

Vitamin D as a part of the endocrine system is an important component in the interaction between the kidney, bone, parathyroid hormone, and the intestine, which maintains extracellular calcium level within normal limits, in order to keep the vital physiologic process and skeletal integrity. Vitamin D is also associated with hypertension, muscular function, immunity, and ability to encounter infection, autoimmune disease, and cancer. The role of vitamin D in immunity is a feedback reaction of paracrine to eliminate inflammation or to influence CD4 T-cell differentiation and or to increase the function of T suppressor cell or combination between both. The active form of vitamin D produces and maintains self immunologic tolerance, some studies show that 1,25(OH)2D inhibits induction of disease in autoimmune encephalomyelitis, thyroiditis, type-1 diabetes mellitus, inflammatory bowel disease (IBD), systemic lupus erythematosus, and collagen-induced arthritis and Lyme arthritis.