Deficiências de minerais

Neste artigo procuramos relatar a situação mundial e brasileira com relação aos micronutrientes, em especial sobre os minerais. Os elementos químicos minerais desempenham funções de grande importância no organismo humano, sendo indispensáveis para o desenvolvimento e a saúde dos indivíduos. Ainda não existe uma avaliação global do estado nutricional dos indivíduos em relação a esses micronutrientes no Brasil, mas os estudos existentes apontam para a necessidade do acompanhamento das tendências alimentares que poderiam levar às suas deficiências com conseqüências adversas para a saúde da população e o desenvolvimento do nosso país.In this paper we will try to report the Brazilian micronutrients status, as well as in worldwide, specifically for minerals. Minerals have major importance on human body, becoming indispensable for the development and health of individuals. There is not yet an integral assessment of micronutrient status in the Brazilian subjects, but there are some studies pointing to the need of observation of alimentary tendencies that might lead to deficiencies, with adverse consequences to the populations health and the development of our countr

Importance and management of micronutrient deficiencies in patients with Alzheimer\u27s disease

Alzheimer\u27s disease (AD) is the most common form of dementia, and it generally affects the elderly. It has been suggested that diet is an intensively modifiable lifestyle factor that might reduce the risk of AD. Because epidemiological studies generally report the potential neuronal protective effects of various micronutrients, the aim of this study was to perform a literature review on the major nutrients that are related to AD, including selenium, vitamins C and E, transition metals, vitamin D, B-complex vitamins, and omega-3 fatty acids

Chemical and radiological characterization of meals served by the COSEAS (USP-SP)

O presente estudo apresenta resultados de análise química de refeições (almoço) oferecidas pelo restaurante do COSEAS (USP), por cinco dias não consecutivos. Essas refeições foram coletadas em triplicata, da mesma forma como oferecida para os usuários, sendo, a seguir, liofilizadas para as análises posteriores. No total, 15 amostras foram coletadas. A análise química de composição centesimal foi realizada segundo as técnicas padronizadas pela AOAC. O conteúdo de alguns elementos minerais (Ca, Fe, K, Na, Se e Zn) foi determinado por análise por ativação neutrônica instrumental. A validação da metodologia foi feita por meio da análise dos materiais de referência. A partir dos dados de concentração, calcularam-se os valores de ingestão de cada nutriente correspondente a esta refeição (40% da ingestão diária total), que foram avaliadas segundo as novas recomendações de nutrientes (Dietary Reference Intakes - DRIs) do National Research Council (USA), considerando a população de mulheres no estágio de vida de 19 a 30 anos. Comparando-se os valores médios encontrados com os valores recomendados, concluiu-se que: para os macronutrientes e os micronutrientes, Fe, Se e Zn, as recomendações foram atingidas; para Ca e K foram deficientes; e para Na excedeu o valor recomendado. Os radionuclídeos 40K, 60Co, 137Cs e 131I foram determinados, nas amostras de dieta, por espectrometria gama; 90Sr por cintilação em meio líquido; e 210Po, 234U, 232Th, 238U, 235U, 228Th, 230Th e 232Th por espectrometria alfa. Verificou-se, a partir dos resultados obtidos, que todos os radionuclídeos analisados se encontram muito abaixo dos limites estabelecidos pela FAO.This study presents the results obtained for the chemical and radiological analyses of lunch meals served in the cafeteria at the University of São Paulo-USP (COSEAS restaurant) in Brazil, on 5 non-consecutive days. On each of the five days, the meals were collected in triplicate and then freeze-dried for analysis totalizing 15 samples. The determination of the proximate composition complied with the AOAC standardized methodologies. The content of Ca, Fe, K, Na, Se, and Zn was determined by instrumental neutron activation analysis and the method validation was performed by certified reference materials analyses. Based on the concentration data, the daily intake of each mineral was calculated (corresponding to 40% of the total daily intake) and compared to the new recommendations set by the National Research Council (USA) considering the 19-30 year-old women range group. Comparing the average values obtained in this study with the recommended values, it was possible to verify that for macronutrients and the micronutrients Fe, Se, and Zn the recommendations were followed; for Ca and K they were deficient and exceeded the recommendation value for Na. The radionuclides 40K, 60Co, 137Cs, and 131I were determined by gamma spectrometry; 90Sr by liquid cintilation and 210Po, 234U, 232Th, 238U, 235U, 228Th, 230Th, and 232Th by alfa spectrometry. All radionuclides are present in concentrations below the limits set by the Food and Agriculture Organization (FAO)

The role of selenoproteins in cancer

Evidências têm demonstrado que distúrbios do metabolismo são comuns em células tumorais, levando ao aumento do estresse oxidativo. A elevação na produção de espécies reativas de oxigênio (EROs) associada à baixa atividade antioxidante tem sido relacionada a vários tipos de câncer. O selênio, micronutriente antioxidante, pode funcionar como um agente antimutagênico, prevenindo transformações malignas de células normais. Realizou-se um levantamento bibliográfico no período 2000 a 2009 mediante consulta à base de dados PubMed (National Library of Medicine´s Medline Biomedical Literature, USA), selecionando-se 39 artigos que avaliaram a relação entre câncer, estresse oxidativo e suplementação com selênio. O efeito protetor desse mineral é especialmente associado à sua presença na glutationa peroxidase e na tioredoxina redutase, enzimas protetoras do DNA e outros componentes celulares contra o dano oxidativo causado pelas EROs. Vários estudos têm demonstrado a expressão reduzida destas enzimas em diversos tipos de câncer, principalmente quando associados a uma baixa ingestão de selênio, que pode acentuar os danos causados. A suplementação de selênio parece ocasionar redução do risco de alguns tipos de câncer diminuindo o estresse oxidativo e o dano ao DNA. No entanto, mais estudos são necessários para esclarecer as doses de selênio adequadas para cada situação (sexo, localização geográfica e tipo de câncer)There are evidences that metabolic disorders are common in tumoral cells, leading to increased oxidative stress. The rising in the production of reactive oxygen species associated to low antioxidant activity have been associated to different types of cancer. Selenium, an antioxidant micronutrient can work as an anti-cancer agent preventing malignant modification in healthy cells. A literature review was carried out in the period 2000-2009 in the database PubMed selecting 39 articles which assessed the relationship between cancer, oxidative stress, and supplementation with selenium. The protective effect of selenium is specially associated to the presence of glutathione peroxidase and of thioredoxin reductase enzymes and with other cell components which protect the tissues against the oxidative damage caused by reactive oxygen species - ROS. Several studies have shown a decrease of these enzymes in many types of cancer, mainly when associated with low selenium consumption, increasing the damage caused by ROS. Selenium supplementation seems to reduce the risk of some types of cancer by stress oxidative reduction and by limiting the damage to DNA. Nevertheless, more studies are necessary to clarify the adequate selenium doses in each situation (gender, geographic localization and type of cancer

Nutritional value of Saccharomyces cerevisiae biomass. Study in generations of rats

Não consta resumo na publicação.The biological value of the proteins of Saccharomyces cerevisiae grown in sugar cane molasses was studied in rats during 3 generations. The animals were fed two levels of yeast protein either 10% or 25% and compared with casein fed controls. In the first generation the PER and body weight were significantly lower for the animals receiving the yeast in their diet. In the 2rd and 3rd generation the growth was retarded even more in relation to what had been observed for the first one, specially at 10% protein level. A decreased male fertility was also observed at litter born from rats fed either 10% or 25% protein. The digestibility for casein was 90% and 80% for single cell protein

Nutritional value of Saccharomyces cerevisiae biomass. Study in generations of rats

Não consta resumo na publicação.The biological value of the proteins of Saccharomyces cerevisiae grown in sugar cane molasses was studied in rats during 3 generations. The animals were fed two levels of yeast protein either 10% or 25% and compared with casein fed controls. In the first generation the PER and body weight were significantly lower for the animals receiving the yeast in their diet. In the 2rd and 3rd generation the growth was retarded even more in relation to what had been observed for the first one, specially at 10% protein level. A decreased male fertility was also observed at litter born from rats fed either 10% or 25% protein. The digestibility for casein was 90% and 80% for single cell protein

Zinc and Selenium Nutritional Status in Vegetarians

A vegetarian diet may have beneficial effects on human health, however when it is not well-balanced may be deficient in some nutrients, as minerals for example. The aim of the present study was to assess the nutritional status of zinc and selenium in vegetarians in the city of SA o pound Paulo. A cross-sectional study was performed, and the inclusion criteria were age a parts per thousand yen 18 years, both gender, no use of food or pharmaceutical supplements. Thirty vegetarian, of both genders, mean age of 27 years and 4,5 years of vegetarianism had performed the study, and their mean BMI was 21,5. Zinc plasma concentration was 71 and 62,5 mu g/dL for men and women and erythrocyte concentration was 37 mu g/gHb for both genders. Selenium concentration was 73,5 and 77,3 mu g/L in plasma and 51,4 and 66,9 mu g/L in erythrocytes for men and women, respectively. These biochemical values show that, according to the references, selenium blood levels are adequate and zinc concentration in erythrocytes is deficient in the studied population. For this reason, vegetarians should be constantly assessed and receive nutritional support to reduce the effects of inadequate zinc status.University of Sao Paulo (USP)CAPES (Coordenacaode Aperfeicoamento de Pessoal de Nivel Superior)CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico