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1.
Ann N Y Acad Sci ; 1446(1): 153-169, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30942488

RESUMO

Nigeria has an alarming prevalence of micronutrient deficiencies that has persisted over decades. National Micronutrient Deficiency Control (MNDC) guidelines describe several interventions to address the issue. This study identified and described currently implemented interventions, assessed coverage and coordination of the interventions, and considered the risk of overdosage and gaps. Methods included reviews of policy and program documents, key informant interviews, market, and pharmacy visits. The study found that an array of MNDC interventions were being implemented, including public health supplementation, mandatory fortification, point-of-use fortification, biofortification, promotion of dietary diversity, voluntary fortification, and ad hoc individual supplement use. Insufficient coordination existed for government, private, and civil society interventions within the health sector and between health and other sectors. Dosages of micronutrients supplied by different interventions were set independently of each other and target populations overlapped. Inadequate implementation of various interventions appeared to reduce the risk of excessive micronutrient intakes, but increased the risk of deficiencies. The risk of excessive intakes will likely increase with improved implementation and scale-up. There is a need to develop effective coordination structures for MNDC in Nigeria that will critically examine the landscape, decide modalities for different interventions, and ensure that both deficiencies and risk of excessive intakes are minimized.


Assuntos
Deficiências Nutricionais/prevenção & controle , Micronutrientes/deficiência , Micronutrientes/toxicidade , Deficiências Nutricionais/epidemiologia , Humanos , Nigéria/epidemiologia , Estado Nutricional
2.
Nutrients ; 9(5)2017 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-28498348

RESUMO

In chronic kidney disease (CKD), accumulation of uremic toxins is associated with an increased risk of death. Some uremic toxins are ingested with the diet, such as phosphate and star fruit-derived caramboxin. Others result from nutrient processing by gut microbiota, yielding precursors of uremic toxins or uremic toxins themselves. These nutrients include l-carnitine, choline/phosphatidylcholine, tryptophan and tyrosine, which are also sold over-the-counter as nutritional supplements. Physicians and patients alike should be aware that, in CKD patients, the use of these supplements may lead to potentially toxic effects. Unfortunately, most patients with CKD are not aware of their condition. Some of the dietary components may modify the gut microbiota, increasing the number of bacteria that process them to yield uremic toxins, such as trimethylamine N-Oxide (TMAO), p-cresyl sulfate, indoxyl sulfate and indole-3 acetic acid. Circulating levels of nutrient-derived uremic toxins are associated to increased risk of death and cardiovascular disease and there is evidence that this association may be causal. Future developments may include maneuvers to modify gut processing or absorption of these nutrients or derivatives to improve CKD patient outcomes.


Assuntos
Microbioma Gastrointestinal , Micronutrientes/toxicidade , Insuficiência Renal Crônica/microbiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Carnitina/administração & dosagem , Carnitina/toxicidade , Colina/administração & dosagem , Colina/toxicidade , Dieta , Humanos , Metilaminas/administração & dosagem , Metilaminas/toxicidade , Micronutrientes/administração & dosagem , Oxalatos/administração & dosagem , Oxalatos/toxicidade , Fosfatos/administração & dosagem , Fosfatos/toxicidade , Fosfatidilcolinas/administração & dosagem , Fosfatidilcolinas/toxicidade , Triptofano/administração & dosagem , Triptofano/toxicidade , Tirosina/administração & dosagem , Tirosina/toxicidade
3.
PLoS One ; 11(4): e0152081, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27116220

RESUMO

Up to 1 billion people are affected by low intakes of the essential nutrient selenium (Se) due to low concentrations in crops. Biofortification of this micronutrient in plants is an attractive way of increasing dietary Se levels. We investigated a promising method of Se biofortification of rice seedlings, as rice is the primary staple for 3 billion people, but naturally contains low Se concentrations. We studied hydroponic Se uptake for 0-2500 ppb Se, potential phyto-toxicological effects of Se and the speciation of Se along the shoots and roots as a function of added Se species, concentrations and other nutrients supplied. We found that rice germinating directly in a Se environment increased plant-Se by factor 2-16, but that nutrient supplementation is required to prevent phyto-toxicity. XANES data showed that selenite uptake mainly resulted in the accumulation of organic Se in roots, but that selenate uptake resulted in accumulation of selenate in the higher part of the shoot, which is an essential requirement for Se to be transported to the grain. The amount of organic Se in the plant was positively correlated with applied Se concentration. Our results indicate that biofortification of seedlings with selenate is a successful method to increase Se levels in rice.


Assuntos
Oryza/metabolismo , Selênio/farmacocinética , Transporte Biológico Ativo , Germinação , Humanos , Hidroponia , Micronutrientes/administração & dosagem , Micronutrientes/farmacocinética , Micronutrientes/toxicidade , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Plântula/metabolismo , Ácido Selênico/administração & dosagem , Ácido Selênico/farmacocinética , Ácido Selênico/toxicidade , Selênio/administração & dosagem , Selênio/toxicidade
4.
Nutr Clin Pract ; 30(4): 559-69, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26113560

RESUMO

The American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) started an intensive review of commercially available parenteral vitamin and trace element (TE) products in 2009. The chief findings were that adult multi-TE products currently available in the United States (U.S.) provide potentially toxic amounts of manganese, copper, and chromium, and neonatal/pediatric multi-TE products provide potentially toxic amounts of manganese and chromium. The multivitamin products appeared safe and effective; however, a separate parenteral vitamin D product is needed for those patients on standard therapy who continue to be vitamin D depleted and are unresponsive to oral supplements. The review process also extended to parenteral choline and carnitine. Although choline and carnitine are not technically vitamins or trace elements, choline is an essential nutrient in all age groups, and carnitine is an essential nutrient in infants, according to the Food and Nutrition Board of the Institute of Medicine. A parenteral choline product needs to be developed and available. Efforts are currently under way to engage the U.S. Food and Drug Administration (FDA) and the parenteral nutrient industry so A.S.P.E.N.'s recommendations can become a commercial reality.


Assuntos
Suplementos Nutricionais/normas , Micronutrientes/normas , Nutrição Parenteral/normas , United States Food and Drug Administration/normas , Adulto , Carnitina/normas , Carnitina/toxicidade , Colina/normas , Colina/toxicidade , Suplementos Nutricionais/toxicidade , Aprovação de Drogas , Humanos , Lactente , Lipotrópicos/normas , Lipotrópicos/toxicidade , Micronutrientes/toxicidade , Oligoelementos/normas , Oligoelementos/toxicidade , Estados Unidos , Vitamina D/normas , Vitamina D/toxicidade , Vitaminas/normas , Vitaminas/toxicidade
5.
JPEN J Parenter Enteral Nutr ; 33(5): 548-62, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19454751

RESUMO

Preexisting micronutrient (vitamins and trace elements) deficiencies are often present in hospitalized patients. Deficiencies occur due to inadequate or inappropriate administration, increased or altered requirements, and increased losses, affecting various biochemical processes and resulting in organ dysfunction, poor wound healing, and altered immune status with deleterious sequelae. Guidelines for the 13 essential vitamins and 10 essential trace elements have been established. These recommendations, however, are applicable to healthy adults and not to critically ill patients, in whom decreased serum levels may indicate actual deficiencies or a deficiency due to redistribution. Benefits of supplementation over and above the daily requirements, which may not result in increased serum levels, are also unclear and may, in fact, be detrimental. Vitamin requirements are increased in disease states, but a similar recommendation for trace elements has not been initiated except for selenium (Se) and zinc (Zn). In practice, a multivitamin preparation and a multiple trace element admixture (containing Zn, Se, copper, chromium, and manganese) are added to parenteral nutrition formulations. Most enteral nutrition preparations also contain adequate amounts of vitamins and trace elements, although bioavailability may be an issue. Detailed information about individual micronutrient use specifically in hospitalized adult patients receiving nutrition therapy will be discussed, emphasizing the practical and clinical aspects. Clinicians are encouraged to think of micronutrients not as nutritional supplements alone but also as therapeutic agents and nutraceuticals.


Assuntos
Micronutrientes/administração & dosagem , Terapia Nutricional , Adulto , Deficiência de Vitaminas , Suplementos Nutricionais , Nutrição Enteral , Humanos , Inflamação/sangue , Absorção Intestinal , Micronutrientes/farmacocinética , Micronutrientes/toxicidade , Política Nutricional , Necessidades Nutricionais , Nutrição Parenteral , Oligoelementos/administração & dosagem , Oligoelementos/sangue , Oligoelementos/deficiência , Vitaminas/administração & dosagem , Vitaminas/sangue , Vitaminas/farmacocinética
6.
Am J Clin Nutr ; 88(3): 863S-6S, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18779310

RESUMO

Copper is an essential nutrient that is toxic in excess. Copper intakes from a balanced diet appear to meet the needs of most healthy individuals, because overt deficiency and toxicity are rare. Some uncertainty, however, persists because of limitations in currently available biomarkers used to assess copper status and the paucity of data available to establish tolerable upper levels of intake. Current policies and regulations pertaining to food fortification, nutritional supplements, and drinking water appear to be effective in providing for adequate copper intakes in many populations, although high levels of exposure, through overzealous fortification, supplementation, or drinking water exposure, may be possible under some circumstances. Surveillance and monitoring programs to evaluate copper exposures of human populations should continue and should be refined as new biomarkers become available.


Assuntos
Cobre/metabolismo , Cobre/toxicidade , Dieta , Suplementos Nutricionais , Exposição Ambiental , Política de Saúde , Humanos , Micronutrientes/metabolismo , Micronutrientes/toxicidade , Estado Nutricional , Abastecimento de Água
7.
Biol Trace Elem Res ; 125(1): 1-12, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18709338

RESUMO

The use of dietary supplements has grown dramatically in the last decade. A large number of dietary and herbal supplements escape regulatory and quality control; components of these preparations are poisonous and may contain, among other toxins, heavy metals. Uncontrolled use of dietary and herbal supplements by special populations, such as the military, may therefore pose a health risk. Clinical symptoms are not always properly attributed to dietary supplements; patients often do not mention supplement use to their health care provider. Therefore, a health risk estimate is hard to make on either the individual or the population level. The literature on this issue was reviewed and discussed in the light of a representative clinical-chemical case study. This case study was performed on a host of preparations that were used by one single individual in the military. Both essential (chromium, copper, zinc, and iron) and poisonous (arsenic, lead, and nickel) trace elements were determined using inductively coupled plasma combined with optical emission spectrometry (ICP-OES) or with mass spectrometry (ICP-MS). Arsenic and lead were detected at exposure levels associated with health risks. These health risks were detected predominantly in hormone-containing supplements and the herbs and botanicals used for performance enhancement. To the extent that this is a representative sample, there is an underestimation of supplement use and supplement risk in the US military, if not in the general population. Since clinical symptoms may be attributed to other causes and, unless patients are specifically asked, health care providers may not be aware of their patients' use of dietary supplements, a strong support of laboratory diagnostics, such as a toxicological screening of blood or urine, is required. In addition, screening of the preparations themselves may be advised.


Assuntos
Suplementos Nutricionais/toxicidade , Humanos , Masculino , Metais/toxicidade , Micronutrientes/toxicidade , Militares
8.
Crit Rev Food Sci Nutr ; 47(3): 267-85, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17453924

RESUMO

In this paper, we review European legislation in the field of micronutrient food supplements and find it wanting. It is shown that the precautionary principle, embedded in European food legislation, pre-empts innovative developments in this field. In view of the scientific advances in micronutrients research, we subsequently critique the precautionary perspective and propose a novel outlook on micronutrients food supplements regulation. However, this requires a transition from the "survival" approach of the current deficiency-related RDAs to a "health-optimization" approach of a n(ew)-RDA. Genomic integrity is central in this envisioned transition.


Assuntos
Suplementos Nutricionais/toxicidade , Legislação sobre Alimentos , Micronutrientes/administração & dosagem , Fenômenos Fisiológicos da Nutrição , Europa (Continente) , Genômica , Promoção da Saúde , Humanos , Micronutrientes/toxicidade , Política Nutricional/legislação & jurisprudência , Medição de Risco
9.
Acta Pharm ; 54(4): 261-76, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15634611

RESUMO

Selenium is a trace element, essential in small amounts, but it can be toxic in larger amounts. Levels in the body are mainly dependent on the amount of selenium in the diet, which is a function of the selenium content of the soil. Humans and animals require selenium for normal functioning of more than about 30 known selenoproteins, of which approximately 15 have been purified to allow characterisation of their biological functions. Selenoproteins are comprised of four glutathione peroxidases, three iodothyronine deiodinases, three thioredoxin reductases, selenoprotein P, selenoprotein W and selenophosphate synthetase. Selenium is essential for normal functioning of the immune system and thyroid gland, making selenium an essential element for normal development, growth, metabolism, and defense of the body. Supportive function of selenium in health and disease (male infertility, viral infections, including HIV, cancer, cardiovascular and autoimmune diseases) is documented in great number of clinical examinations. A great number of studies confirm that selenium supplementation plays a preventive and therapeutical role in different diseases. Definitive evidence regarding the preventive and therapeutical role of selenium as well as the exact mechanism of its action should be investigated in further studies. Investigations in Croatia indicate a possibility of inadequate selenium status of people in the area.


Assuntos
Enzimas/metabolismo , Micronutrientes/metabolismo , Proteínas/metabolismo , Selênio/metabolismo , Animais , Suplementos Nutricionais , Interações Medicamentosas , Humanos , Micronutrientes/deficiência , Micronutrientes/toxicidade , Selênio/administração & dosagem , Selênio/deficiência , Selênio/toxicidade , Selenoproteína P , Selenoproteína W , Selenoproteínas
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