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2.
Anticancer Res ; 40(1): 491-499, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31892604

RESUMO

This article is a narrative review of recent epidemiological findings regarding ultraviolet-B (UVB) dose or exposure, serum 25-hydroxyvitamin D [25(OH)D] concentrations, vitamin D supplementation, and genetic variations in 25(OH)D concentration for incidence, survival, and mortality rates of overall and breast, colorectal, and prostate cancer. According to ecological studies, solar UVB doses are inversely correlated with incidence/mortality rates for about 20 cancer types. Observational studies support a role of higher 25(OH)D concentrations in reducing risk of breast and colorectal cancer incidence and mortality rates but, for prostate cancer, in increasing incidence rates while reducing mortality rates. Mendelian randomization studies offer little support for vitamin D in reducing cancer risk. Their primary limitation is that they only investigate small variations in genetically predicted 25(OH)D concentration near the population mean value. The secondary analyses from the VITAL clinical trial indicated significant reductions from 2000 IU/d of vitamin D3 supplementation in all-cancer incidence and mortality rates for selected subgroups. Thus, Hill's criteria for causality in a biological system are now largely satisfied for supporting the claim that vitamin D reduces the risk of cancer incidence and death.


Assuntos
Neoplasias/epidemiologia , Vitamina D/metabolismo , Suplementos Nutricionais , Humanos , Neoplasias/sangue , Neoplasias/mortalidade , Estudos Observacionais como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Vitamina D/sangue
3.
Anticancer Res ; 40(1): 501-509, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31892605

RESUMO

BACKGROUND: Intensive scientific debate is ongoing about whether moderate solarium use increases melanoma risk. The authors of some recent publications demand the debate be closed and propose "actions against solarium use for skin cancer prevention" because new studies have convincingly demonstrated causality. This minireview aims to investigate whether those demands are sufficiently supported by present scientific knowledge and comply with the principles of evidence-based medicine. MATERIALS AND METHODS: We performed a systematic literature search (through June 2019; PubMed, ISI Web of Science) to identify publications investigating how solarium use affects melanoma risk. RESULTS: We found no studies that demonstrate a causal relationship between moderate solarium use and melanoma risk. Results of cohort and case-control studies published to date, including recent investigations, do not prove causality, and randomized controlled trials providing unequivocal proof are still lacking. Moreover, the overall quality of observational studies is low as a result of severe limitations (including unobserved or unrecorded confounding), possibly leading to bias. We also disagree with recent claims that Hill's criteria for the epidemiological evidence of a causal relationship between a potential causal factor and an observed effect are fulfilled in regard to the conclusion that moderate solarium use per se would increase melanoma risk Conclusion: Current scientific knowledge does not demonstrate a causal relationship between moderate solarium use and melanoma risk. Therefore, the debate is not closed.


Assuntos
Melanoma/epidemiologia , Banho de Sol , Animais , Humanos , Fatores de Risco , Raios Ultravioleta
4.
Eur J Clin Nutr ; 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996793

RESUMO

Over the past two decades, many studies reported the benefits of higher 25-hydroxyvitamin D [25(OH)D] concentrations for nonskeletal effects. Researchers found significant benefits in reducing risk of acute respiratory tract infections, many types of cancer, type 2 diabetes mellitus, premature death, and adverse pregnancy and birth outcomes. In addition, 25(OH)D concentrations are low for various reasons in several categories of people, including the obese, those with dark skin living at higher latitudes, the elderly, and those who do not eat much eggs, fish, meat, or vitamin D fortified milk. Measuring 25(OH)D concentrations is one way to both increase the awareness of vitamin D's importance in maintaining good health and to encourage vitamin D supplementation or increased solar ultraviolet-B exposure to sustain well-being throughout life by reducing disease incidence. Although 20 ng/ml seems adequate to reduce risk of skeletal problems and acute respiratory tract infections, concentrations above 30 ng/ml have been associated with reduced risk of cancer, type 2 diabetes mellitus, and adverse pregnancy and birth outcomes. Thus, judicious testing of 25(OH)D concentrations could reduce disease incidence and make treatment expenditures more cost-effective.

8.
Nutrients ; 11(10)2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615079

RESUMO

Serum 25-hydroxyvitamin D (25(OH)D) concentrations are low in Mongolia, averaging 22 ng/mL in summer and only 8 ng/mL in winter. Mongolians have high incidence and/or prevalence of several diseases linked to low 25(OH)D concentrations, including ischemic heart disease, malignant neoplasms, cirrhosis of the liver, ischemic stroke, lower respiratory tract infections, preterm birth complications, and diabetes mellitus. Fortifying regularly consumed foods such as flour, milk, and edible oils with vitamin D3 could raise 25(OH)D concentrations by about 10 ng/mL. However, to achieve 25(OH)D concentrations of 30-40 ng/mL in adults, vitamin D intakes of 1000 to 4000 IU/day would be required, making personal supplement use necessary. On the basis of prospective observational studies and clinical trials of disease incidence or known mortality rates and adverse pregnancy and birth outcomes, raising mean serum 25(OH)D concentrations to 40 ng/mL would likely reduce incidence and mortality rates for those and other diseases, reduce the rate of adverse pregnancy and birth outcomes, and increase mean life expectancy by one year or more.

10.
Diabetes Metab Syndr Obes ; 12: 1437-1447, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496777

RESUMO

The global death toll from noncommunicable diseases is exceptionally high, reported to cause 71% of global deaths worldwide. Metabolic syndrome risk factors, especially excessive adiposity and obesity, are at the heart of the problem resulting in increased co-morbidities such as cardiometabolic diseases and cancer, increased health costs, poorer quality of life, and shortened survival. Vitamin D3 can positively reverse many of these adverse effects and outcomes through blocking signaling mechanisms that predispose to cardiometabolic and metastatic disease. As an affordable natural agent, vitamin D3 can be used to counteract obesity-induced inflammation, block early adipogenesis, enhance glucose uptake, counteract hyperleptinemia, ameliorate insulin resistance, and reduce hypertension. This is supported by data from in vitro, in vivo and epidemiological studies and clinical trials. We propose that everyone in general and obese patients in particular consider raising 25-hydroxyvitamin D levels through UVB exposure and/or supplemental vitamin D3 intake to reduce cardiometabolic and metastatic disease and increase longevity.

11.
Nutrients ; 11(9)2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31484329

RESUMO

Serum 25-hydroxyvitamin D (25(OH)D) has been largely associated with latitude and sunshine exposure across several regions. According to previous results, 25(OH)D concentrations are, on average, relatively low in countries with abundant sunshine, including those of the Middle East and North Africa region, as well as lower-latitude Europe. The standard explanation for this phenomenon is that people wear concealing clothing because of cultural and religious practices and that high temperatures in summer limit direct sun exposure. However, the role of diet in the development of profound hypovitaminosis D has not been adequately explored in those countries. To examine how diet affects vitamin D status in the Middle Eastern and European countries, a search was conducted for papers from that region reporting 25(OH)D concentrations. Papers were sought that reported summertime and wintertime 25(OH)D concentrations for healthy nonpregnant adults representative of the entire population. Data from 15 Middle Eastern and European countries were found through this search. Data for postmenopausal women from 19 European countries were also obtained. Dietary supply data for animal products containing vitamin D (animal fat, eggs, ocean fish, animal meat, and milk) were obtained from the Food and Agriculture Organization of the United Nations. Latitude and a solar UVB dose index also were obtained for each country. For the 15-country study, energy from dietary factors was highly correlated with latitude, making it difficult to separate the effects of UVB exposure and dietary factors. However, for the 19-country study, dietary factors were only weakly correlated with latitude. In that study, ocean fish was the most important single dietary factor affecting serum 25(OH)D concentration for postmenopausal women in various European countries, but animal fat and meat also contributed. Because this is an ecological study, further research is encouraged to evaluate and extend the findings.

12.
Endocrine ; 66(2): 428-429, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31392627
14.
Nutrients ; 11(6)2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31200428

RESUMO

Scragg reports increasing evidence for differences in the thresholds for serum 25-hydroxyvitamin D [25(OH)D] concentration [vitamin D repletion] that need to be reached in populations observationally, or to be achieved by vitamin D supplementation in deficiency, before health benefits become apparent in different conditions [...].

15.
Curr Nutr Rep ; 8(3): 203-211, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31055734

RESUMO

PURPOSE OF REVIEW: This review summarizes the understanding of vitamin D3's role in reducing risk of cancer incidence and mortality. RECENT FINDINGS: Recent randomized clinical trials and observational studies of participants who took part in vitamin D3 supplementation studies provide increasing evidence that concentrations of serum 25-hydroxyvitamin D3 [25(OH)D3] up to ~ 60 ng/ml are inversely correlated with all cancer and some specific cancers' incidence and death, with a stronger effect on survival and death than on incidence. Mechanisms linking vitamin D3 to effects on cellular proliferation, anti-angiogenesis, and anti-metastasis continue to be found. Vitamin D3 reduces cancer risk causally. Maintaining 25(OH)D3 in the range of 40-60 ng/ml reduces the risk of many cancers. Raising 25(OH)D3 concentrations after diagnosis to that range increases survival rates and could significantly reduce the global burden of cancer incidence and death.

17.
Artigo em Inglês | MEDLINE | ID: mdl-30893924

RESUMO

: Hawai'i Island often receives extreme (UV Index ≥ 11) solar ultraviolet radiation (UVR). While the UV Index (UVI) has been measured since 1997 at Hawai'i's high-altitude Mauna Loa Observatory (MLO), measurements where people live and recreate are rare. We measured UVI on the face of a rotating mannequin head with UVR sensors at its eyes, ears and cheeks while simultaneously measuring the UVI with a zenith-facing sensor at MLO and seven sites at or near sea level from 19 July to 14 August 2018. The mannequin sensors received higher UVR at midmorning and midafternoon than at noon. For example, at sea level the peak UVI at the left cheek was 5.2 at midmorning and 2.9 at noon, while the horizontal UVI at noon was 12.7. Our measurements were supplemented with wide-angle (190° and 360°) sky photographs and UV images of the mannequin head. Because the UVI applies to horizontal surfaces, people in tropical and temperate latitudes should be informed that their face may be more vulnerable to UVR at midmorning and midafternoon than at noon. Finally, our instruments provided opportunities to measure unexpected UVR-altering events, including rare biomass smoke over MLO and spectroscopic measurements of substantial UVR-absorbing sulfur dioxide in the eruption plume of the Kilauea volcano.


Assuntos
Atmosfera , Luz Solar , Clima , Hawaii , Humanos , Manequins , Dióxido de Enxofre/química , Erupções Vulcânicas
18.
19.
Hormones (Athens) ; 18(1): 23-35, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30209779

RESUMO

Vitamin D, traditionally well known for its role in maintaining optimal health through its contribution to calcium metabolism and skeletal health, has received increased attention over the past two decades, with considerable focus being placed on its nonskeletal benefits. This paper is a narrative review of the nonskeletal health benefits of vitamin D, of particular interest to inhabitants of Mediterranean countries, namely, autism, cancer, cardiovascular disease, chronic obstructive pulmonary disease, dental caries, diabetes mellitus, erectile dysfunction, hypertension, metabolic syndrome, respiratory tract infections, all-cause mortality, and pregnancy and birth outcomes, because of the relatively high incidence and/or prevalence of these disorders in this region. Currently, the best evidence is coming out of observational studies related to serum 25-hydroxyvitamin D [25(OH)D] concentrations. Vitamin D clinical trials have generally been poorly designed and conducted, usually being based on vitamin D dose rather than 25(OH)D concentration. The optimal 25(OH)D concentration is above 75 nmol/l (30 ng/ml), with even better health outcomes in the range of 100-150 nmol/l. Achieving these concentrations with vitamin D3 supplements will require 1000-4000 IU/day of vitamin D3. Sensible sun exposure should also be encouraged. Countries should also consider fortifying grain and dairy products with vitamin D3.


Assuntos
Transtorno do Espectro Autista , Hormônios e Agentes Reguladores de Cálcio/administração & dosagem , Doenças Cardiovasculares , Colecalciferol/administração & dosagem , Cárie Dentária , Neoplasias , Complicações na Gravidez , Vitamina D/sangue , Transtorno do Espectro Autista/sangue , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/prevenção & controle , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Cárie Dentária/sangue , Cárie Dentária/epidemiologia , Cárie Dentária/prevenção & controle , Feminino , Humanos , Região do Mediterrâneo/epidemiologia , Neoplasias/sangue , Neoplasias/epidemiologia , Neoplasias/prevenção & controle , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/prevenção & controle
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