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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Effects of exercise on appetite, food intake and the gastrointestinal hormones Ghrelin and Peptide YY

King, James A. January 2010 (has links)
Gut hormones are implicated in the regulation of energy balance. The studies in this thesis have examined the effects exercise on gut hormones (acylated ghrelin and peptide YY3-36), appetite and food intake, over extended durations. Sixty-nine young, healthy, predominantly Caucasian males were recruited to six studies. The age, height and body mass of the participants were: 22.4 ± 0.3 y, 1.80 ± 0.1 m, 76.2 ± 1.0 kg (mean ± SEM). In study one, 90 min of resistance exercise did not influence appetite or energy intake over 24 h of assessment, yet stimulated a latent preference for carbohydrate rich foods. Study two demonstrated that appetite was suppressed during 60 min of swimming but was elevated after consuming a post-exercise meal. Plasma acylated ghrelin was suppressed during swimming but was unaltered after. Energy/macronutrient intake remained unchanged. In study three, 60 min of brisk walking (45 ± 2% of max) did not influence appetite, energy/macronutrient intake or plasma concentrations of acylated ghrelin during an eight hour observation period. Study four showed that 90 min of treadmill running (69 ± 1% of max) transiently suppressed appetite and acylated ghrelin but did not influence these variables, or energy/macronutrient intake within 22.5 h after exercise. The findings of study five suggest that the suppression and subsequent rebound in plasma acylated ghrelin after exercise may be related to a delayed voluntary decision to eat after. Finally, study six showed that appetite, food intake and circulating concentrations of acylated ghrelin and peptide YY3-36 are responsive to acute deficits in energy induced by food restriction but are not sensitive to equivalent energy deficits induced by exercise. This thesis has shown that exercise transiently alters circulating levels of acylated ghrelin and peptide YY3-36 in directions expected to inhibit appetite however no changes are seen after exercise. Conversely, food restriction elicits marked compensatory changes in circulating acylated ghrelin and peptide YY3-36. This thesis also demonstrates that resistance exercise, brisk walking and running do not stimulate appetite or energy intake over defined periods, even when the energy expenditure elicited is high. Swimming appears to increase appetite in the latter hours after exercise.
22

Dietary intake and factors affecting vitamin D status of Middle Eastern people in the UK

Ahmed, Wassan Abdel-Jaleel January 2012 (has links)
Vitamin D is derived through the action of solar ultraviolet B radiation on skin and from a limited number of natural food sources, fortified foods and supplements. It is well known that vitamin D plays an active role for calcium and phosphorus absorption but there is also growing evidence of an association between vitamin D insufficiency and various chronic diseases. Middle Eastern populations are known to be at risk of vitamin D deficiency due to a diet low in vitamin D and low sunshine exposure. Obesity is also a risk factor since vitamin D is sequestered in body fat. This thesis examined dietary intake of vitamin D, obesity and other risk factors for deficiency in Middle Eastern people in the UK. A questionnaire based survey was undertaken with 242 Middle Eastern respondents. A total of 85% of the sample was estimated to have a vitamin D intake <5 µg/d. Other risk factors for vitamin D insufficiency included covering skin from sunlight (84% females); low use of supplements (18.5%) and being overweight or obese (49% males and 44% females). Vitamin D intake was lowest in those with primary (1.8 µg/d) and secondary school (2.1 µg/d) education compared to higher education (3.6 µg/d). The survey was followed by dietary assessment of 28 Iraqi adults using repeat 24 hour recalls. The results concurred with the survey: mean intake of vitamin D was (3.2±4.4 µg/d) and 78.5% were overweight or obese. Finally, overweight participants were recruited to observe the effect of fat loss on vitamin D status. Serum 25(OH)D concentrations was measured in Middle Eastern (n=12) and Caucasian adults (n=24). Firstly seasonal changes were observed between October and January (with no weight loss). Then participants were advised on weight reduction to observe the effect of fat loss on serum 25(OH)D. Vitamin D deficiency (<25 nmol/l) was observed in 67% of the Middle Eastern group in October increasing to 92% in January. Of the 36 participants, only 17 lost ≥1kg of fat mass between January and April. No difference was found in serum 25(OH)D between those that lost fat mass and those that did not, and no correlation was found between the amount of fat lost and change in 25(OH)D. In the total sample, there was a negative association between serum 25(OH)D and waist circumference and waist-hip ratio, but no correlation was found between 25(OH)D and fat mass, thus indicating a relationship with visceral fat stores rather than total fat mass.
23

The role of genetics in regulation of weight loss and food intake

Bandstein, Marcus January 2016 (has links)
While obesity is a world leading health problem, the most efficient treatment option for severely obese patients is Roux-Y gastric bypass (RYGB) surgery. However, there are large inter-individual differences in weight loss after RYGB surgery. The reasons for this are not yet elucidated and the role of genetics in weight loss-regulation is still not fully understood. The main aim for this thesis was to investigate the effects of common obesity-associated genetic variants and their effect on weight loss and food intake. We examined if the weight loss two years following RYGB surgery depends on the  FTO genotype, as well as pre-surgery vitamin D status. For FTO AA-carriers, the surgery resulted in a 3% per-allele increased excess BMI loss (EBMIL; P=0.02). When split by vitamin D baseline status, the EBMIL of vitamin D deficient patients carrying AA exceeded that of vitamin D deficient patients carrying TT by 14% (P=0.03). No such genotypic differences were found in patients without pre-surgery vitamin D deficiency. As the influence of individual single nucleotide polymorphisms may be small, we identified a novel method to combine SNPs into a genetic risk score (GRS). Using the random forest model, SNPs with high impact on weight loss after RYGB surgery were filtered out. An up to 11% lower EBMIL with higher risk score was estimated for the GRS model (p=0.026) composed of seven BMI-associated SNPs (closest genes: MC4R, TMEM160, PTBP2, NUDT3, TFAP2B, ZNF608 and MAP2K5). Pre-surgical hunger feelings were found to be associated with EBMIL and the SNP rs4846567. Before surgery, patients filled out the Three Factor Eating Questionnaire and were genotyped for known BMI and waist-hip ratio (WHR) associated SNPs. Patients with the lowest hunger scores had up to 32% greater EBMIL compared to the highest scoring patients (P=0.002). TT-allele carriers of rs4846567 showed a 58% lower hunger feelings. TT- carriers also showed a 51% decrease in disinhibition, but no significant impact on cognitive restraint was observed. Due to the association of eating behaviour and weight loss, acute effects on DNA methylation in response to a food intake intervention of a standardized meal were also investigated. After food intake, 1832 CpG sites were differentially methylated compared to the baseline after multiple testing correction. When adjusted for white blood cell fractions, 541 CpG sites remained. This may be interpreted as that the immune system is playing an active role in the response to food intake and highlights the dynamic nature of DNA-methylation. These findings will contribute to a better care for morbidly obese patients. Post-surgical treatment may be optimized so that patients with a less favourable genetic profile may receive additional support for weight loss and weight management. This may be considered as a step in the transition towards personalized medicine.
24

Extinction of fear-cue induced inhibition of eating in male and female rats: Activation of brainstem nuclei

Kuthyar, Meghana January 2013 (has links)
Thesis advisor: Gorica D. Petrovich / Thesis advisor: Christina Reppucci / We are interested in exploring the instances in which environmental controls can override physiologic or homeostatic cues, and additionally the areas of the brain that might be implicated in such behavioral effects. For this study, we replicated a previously established behavioral finding in which male and female rats show fear-cue induced inhibition of eating, and that female rats take longer than male rats to extinguish this behavior. We assessed brain activation via Fos-expression in the NTS and DMX in the brainstem and found that males had higher brainstem activation than females during extinction of fear-cue induced inhibition of eating. Additionally, female experimental rats had suppressed activity in the caudal NTS compared to female control rats. The data from this study support our hypotheses that there are distinct activation patterns in the brainstem during the extinguishing of inhibition of eating, and that there are sex differences in these activation patterns. / Thesis (BS) — Boston College, 2013. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Psychology Honors Program. / Discipline: Psychology.
25

Sex Differences in Orexin Activation Patterns of Fear-Cue Induced Inhibition of Eating in Rats

Newmark, Jordan A. January 2013 (has links)
Thesis advisor: Gorica Petrovich / Thesis advisor: Christina Reppucci / In order to understand the neurobiological basis for the phenomenon in which environmental cues override physiological cues to influence the behavioral control of feeding, we utilized an animal model for fear-cue induced inhibition of eating. Female rats that had learned to associate a tone with foot-shocks showed inhibition of eating across three extinction tests, whereas male rats that had received tone-shock pairings extinguished their inhibition of eating after the first test day. We assessed activation of orexin (ORX), a neuropeptide involved in eating and arousal, in the lateral hypothalamic area (LHA) of the brains of male and female control and experimental rats during the final test day. Female rats exhibited greater recruitment of ORX neurons in the LHA than male rats; there was no difference in ORX activation between control and experimental groups of either sex, indicating that ORX is involved in sex differences in fear-cue induced inhibition of eating. / Thesis (BS) — Boston College, 2013. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: College Honors Program. / Discipline: Psychology.
26

Densidade energética: relação com variáveis demográficas, de estilo de vida, nutricionais e socioeconômicas em amostra representativa da população adulta do município de São Paulo / Energy density: association with demographic, lifestyle, nutritional and socioeconomic variables in a representative sample of adult population in the city of São Paulo.

Stella, Roberta Horschutz 05 September 2008 (has links)
Introdução - A densidade energética (DE), definida como a quantidade de energia por unidade de peso, é um importante fator na ingestão de alimentos e no valor calórico total da alimentação. Dessa forma, é uma característica da dieta que pode estar envolvida na qualidade da alimentação e no controle de peso. Objetivo - Analisar a relação entre a DE da dieta com variáveis demográficas, de estilo de vida, nutricionais e socioeconômicas em amostra representativa da população adulta do Município de São Paulo. Métodos - Foram utilizados dados secundários do projeto em Políticas Públicas, intitulado \"Inquérito de Saúde no Município de São Paulo - ISA-Capital\". Trata-se de um estudo transversal, de base populacional. O grupo de estudo foi composto por adultos, de ambos os sexos (N=710). O consumo alimentar foi medido através do método Recordatório de 24 horas. O consumo relatado foi transformado em energia e nutrientes com a utilização do software Nutrition Data System (NDS). A DE da dieta foi estimada através de três métodos: 1- inclusão de todos os alimentos e bebidas; 2- inclusão de todos os alimentos e bebidas calóricas que contenham, no mínimo, 5 Kcal/100g; 3- inclusão de todos os alimentos e exclusão de todas as bebidas. Para avaliar as relações entre a densidade energética da dieta e as variáveis demográficas, de estilo de vida, e socioeconômicas de interesse, foi utilizada a análise de regressão linear múltipla. Resultados: A população estudada foi composta por 56,7% de mulheres, 61,1% da etnia branca e 60,1% com situação conjugal unida/casada. A idade mínima foi de 20 anos e a idade máxima de 59 anos, com média de 36,2 anos. Os valores médios encontrados para a DE1, DE2 e DE3 foram 1,32 kcal/g (EP=0,01), 1,35 kcal/g (EP=0,01) e 1,95 kcal/g (EP=0,02), respectivamente. No modelo múltiplo, a escolaridade do indivíduo e a situação de trabalho \"em atividade\" associaram-se inversamente, ajustado por etnia para DE1 e DE2. Para DE3, foi verificada associação direta para etnia \"outras\" e inversa para hábito de fumar \"ex-fumante\". Conclusões: As médias de densidade energética encontradas no estudo mostraram-se superiores aos poucos estudos populacionais Resumo disponíveis. Os resultados apontados pelos diferentes métodos de cálculo da densidade energética sugerem que a contribuição dos líquidos não pode ser subestimada. / Introduction: Energy density (ED), defined as the amount of energy per unit weight, is a major factor related to food intake and total dietary energy. It is a dietary component that may be involved with diet quality and weight control. Objective: To assess the association between dietary ED and demographic, lifestyle, nutritional and socioeconomic variables in a representative sample of adult population in the city of São Paulo. Methods: A population-based, cross-sectional study was conducted based on secondary data from the Public Policies project, \"Health Survey in the City of São Paulo - ISA-Capital\". The study sample comprised both male and female adults (N=710). Food intake was measured using a 24-hour food recall. The reported intake was converted into energy and nutrients by the Nutrition Data System (NDS) program. Dietary ED was estimated through three different approaches: 1- inclusion of all foods and beverages; 2- inclusion of all energetic foods and beverages with a calorie content of at least 5 kcal/100 g; 3- inclusion of all foods and exclusion of all beverages. A multiple linear regression analysis was carried out to assess the associations between dietary ED and the study variables. Results: In the sample studied, 56.7% were women, 61.1% were White and 60.1% were either married or living with a partner. Mean age was 36.2 years, ranging between 20 and 59 years. Mean ED1, ED2 and ED3 were 1.32 kcal/g (SE=0.01), 1.35 kcal/g (SE=0.01) and 1.95 kcal/g (SE=0.02), respectively. In the multiple regression analysis, schooling and \"active\" working status were inversely associated, after adjusting for ethnicity, with ED1 and ED2. For ED3, there was found a direct association with \"other\" ethnicity and an inverse association with \"former smoking\". Conclusions: Mean energy densities found in the study were higher than those reported in few other population-based studies available. The results obtained through the different approaches for ED estimation indicate that the contribution of liquids should not be underestimated.
27

Consumo alimentar de açúcares de adição por adolescentes residentes no município de São Paulo / Added sugar intake among adolescents living in the city of São Paulo

Paternez, Ana Carolina Almada Colucci 13 May 2009 (has links)
Objetivo: Investigar o consumo alimentar de açúcares de adição em adolescentes residentes no município de São Paulo, assim como os fatores que influenciam tal consumo. Métodos: Obteve-se uma amostra probabilística de 793 adolescentes por conglomerados. Aplicou-se um recordatório alimentar de 24 horas e um segundo recordatório em uma subamostra. O consumo alimentar habitual de energia, nutrientes e alimentos foi estimado pelos métodos propostos pela Iowa State University (ISU) e pelo National Cancer Institute (NCI). Resultados: Em média, os açúcares de adição contribuíram com 12,28% da energia consumida pelos adolescentes (sem diferença entre os sexos), sendo o refrigerante o alimento que mais contribuiu para esta ingestão. A escolaridade do chefe da família e a consumo de outros macronutrientes (proteínas, gorduras e carboidratos exceto açúcares de adição) exerceram efeito independente sobre o consumo de açúcares de adição. O aumento do consumo de calorias provenientes dos açúcares de adição determinou aumento da ingestão de gorduras e redução da ingestão de carboidratos exceto açúcares de adição e proteínas. Maior porção mediana do consumo de leite, carnes, frutas, suco industrializado, refrigerante e achocolatado em pó foi identificada entre os adolescentes com consumo excessivo de açúcares. Conclusões: A contribuição percentual dos açúcares de adição à energia consumida pelos adolescentes do município de São Paulo está acima das recomendações atuais e o consumo excessivo de açúcares exerceu efeito na ingestão e na adequação do consumo de macro e micronutrientes e no consumo de alimentos de maior densidade nutritiva. Essas evidências corroboram as recomendações nacionais e internacionais para redução do consumo de açúcares e apontam a necessidade de ações educativas sobre alimentação saudável direcionadas aos adolescentes. / Objective: To measure added sugar intake and assess the effect of this intake on the diet of adolescents living in the city of São Paulo. Methods: The study sample comprised 793 male and female adolescents selected from a population-based cross-sectional study based on a household survey conducted between March and December 2003. Food intake was assessed through 24-hour food recalls and then an adjustment approach was applied using repeat data. Food intake of energy, nutrients and foods was measured by the methods developed at Iowa State University (ISU) and National Cancer Institute (NCI). Results: Added sugars contributed on average to 12.28% of energy consumed in adolescents (no difference between males and females). Their main source was soft drinks. Family head schooling and other macronutrients intake had an independent effect on added sugar intake. Increased intake of calories from added sugars resulted in increased fat intake and decreased consumption of carbohydrates except sugars and protein. Higher median percent intake of milk, meat, fruit, processed juice, soft drink and chocolate milk was seen among adolescents with excess sugar intake. Conclusions: The percent contribution from added sugars to energy consumed among adolescents in the city of São Paulo is higher than current recommendations. Excess sugar intake had a negative effect on macronutrient and micronutrient intake and adequacy on the consumption of foods of high nutrient density. These findings corroborate Brazilian and international recommendations for reduction of sugar intake and points to the need of education actions targeting adolescents to promote healthy eating.
28

Associação do consumo alimentar com o status de ferro de mulheres saudáveis na idade reprodutiva / Association of food intake with iron status among healthy women at childbearing age

Dias, Gisele Cristina 13 June 2017 (has links)
Uma dieta adequada em ferro biodisponível é fundamental para a prevenção da anemia por deficiência de ferro entre mulheres na idade reprodutiva, que são grupo de alto risco para essa morbidade. Dados da Organização Mundial da Saúde indicam que no Brasil, 19% das mulheres não grávidas em idade reprodutiva são anêmicas. Identificar fatores dietéticos associados com o status de ferro pode nortear políticas atuais voltadas à redução da prevalência de anemia, como é a fortificação de farinhas de trigo e milho com ferro. O objetivo deste estudo foi avaliar a associação entre o consumo habitual de alimentos e o status de ferro de mulheres saudáveis na idade reprodutiva. Foram incluídas 127 mulheres entre estudantes de graduação e de pós-graduação de uma Universidade de São Paulo, com idades entre 18 e 45 anos, saudáveis (relato de menstruação regular e ausência de doenças crônicas ou parasitose intestinal) e não expostas a fatores não dietéticos associados com a deficiência de ferro (gravidez, lactação ou doação de sangue recentes). Foram excluídas do estudo as mulheres com alterações hematológicas ou do status inflamatório e aquelas com dados dietéticos inválidos. A partir de três registros alimentares (RA) e de um questionário de frequência alimentar (QFA), estimou-se o consumo habitual de 30 grupos de alimentos, utilizando a estratégia estatística Multiple Source Method (MSM). Os marcadores do status de ferro utilizados foram ferritina sérica, saturação de transferrina e hemoglobina. Associações foram testadas por análise de regressão linear múltipla, controlando-se pelas covariáveis: ingestão energética habitual, índice de massa corporal, uso de anticoncepcionais hormonais, nível de atividade física, cor de pele autodeclarada, tipo da dieta autodeclarada, idade e escore de fluxo menstrual. As análises foram realizadas no programa SPSS versão 21. Do total de 127 mulheres avaliadas, 16 (12,6%) apresentaram deficiência de ferro (ferritina sérica <15 ng/mL), sendo que 4 delas (3,1%) eram anêmicas (Hb<12g/dL). Valores de ferritina foram positivamente associados com o consumo de \"carnes totais e embutidos\" (&#946; = 0,3%; p = 0,032). Por outro lado, o grupo de \"frutas e sucos naturais\" associou-se negativamente com esse biomarcador (&#946; = - 0,1%; p = 0,039). Uma associação direta entre valores de saturação de transferrina e o consumo de \"carnes bovinas\" foi também encontrada (&#946; = 0,078; p = 0,030). Nenhuma estimativa de consumo habitual de alimentos correlacionou-se com as concentrações circulantes de hemoglobina, ainda que uma forte associação negativa entre esse biomarcador e o relato de restrição dietética de carnes tenha sido observada (&#946; = -0,582; p = 0,006). Entre mulheres adultas saudáveis, estimativas de consumo habitual de carnes e frutas podem predizer variações interindividuais nos biomarcadores do status de ferro. Visando a redução do risco para deficiência de ferro, as recomendações de ingestão desses alimentos devem ser contextualizadas num padrão alimentar saudável e variado, com foco especial na adequação do consumo de carnes não processadas, frutas e sucos naturais. / Dietary adequacy in bioavailable iron is essential to prevent iron deficiency anemia among women at childbearing age, population groups at high-risk for this morbidity. Data from the World Health Organization indicate that, in Brazil, 19% of non-pregnant women at childbearing age are anemic. Identifying dietary factors associated with iron status may guide current policies aimed at lowering the prevalence of anemia, such as the fortification of wheat and corn flours with iron. The aim of this study was to evaluate the association of usual food intake with iron status biomarkers among healthy women at childbearing age. We included 127 students of University of São Paulo aged 18 to 45 years, healthy (self-reporting of regular menstruation and lack of a diagnosed chronic diseases or an intestinal parasitosis) and not exposed to non-dietary factors associated with iron deficiency (recent pregnancy, lactation or blood donation). Cases of hematologic or inflammatory status alterations as well as those with invalid dietary data were excluded from the study. Data from three diet records (DR) and a food frequency questionnaire (FFQ) were used to estimate the usual intake of 30 food groups by employing as the statistical approach the Multiple Source Method (MSM). Biomarkers of iron status were serum ferritin, transferrin saturation index and hemoglobin. Multiple linear regression analysis was used to test associations, with adjustments for the covariates: energy intake, body mass index, hormonal contraceptive use, physical activity level, self-reported skin color, self-reporting of meat dietary restriction, age and a menstrual blood loss score. Analysis were performed in the SPSS program version 21. Among all women, 16 (12.6%) had iron deficiency (serum ferritin < 15 ng/mL), 4 of them (3.1%) were anemic (Hb<12g/dL). In the adjusted models, ferritin values were positively associated with \"total meat and sausages\" intake (&#946; = 0.3%; p = 0.032). On the other hand, \"fruits and natural juices fruits\" intake was negatively associated with this biomarker (&#946; = -0.1%; p = 0.039). A direct association between the transferrin saturation values and \"bovine meat\" intake was also found (&#946; = 0.078; p = 0.030). None of the usual food intake measures was correlated with circulating hemoglobin concentrations, although a strong negative association between this biomarker and self-reporting of meat dietary restriction has been observed (&#946; = - 0.582; p = 0.006). Conclusion: Among adult healthy women, estimates of usual meat and fruit intakes may predict between-person variability of iron status biomarkers. In order to reduce iron deficiency risk, recommendations regarding habitual consumption of these foods must be contextualized in a healthy and varied diet, focusing on the choice of non-processed meats,fruits and natural fruit juice.
29

Ingestão habitual de alimentos entre indivíduos do Município de São Paulo - estudo de base populacional / Habitual food intake among individual from São Pulo - Brazil a population-based survey

Verly Junior, Eliseu 11 January 2012 (has links)
Introdução: A estimativa da ingestão habitual de alimentos requer o uso de técnicas estatísticas apropriadas. Para alguns alimentos, é possível observar consumo igual a zero em um ou vários dias de coleta, mesmo em indivíduos que os consomem periodicamente. Assim, os métodos devem ser capazes de tratar duas questões: 1) a distribuição com zero inflacionado; e 2) a correlação existente entre a probabilidade de consumir um alimento e a quantidade (tamanho da porção) consumida do mesmo. Objetivo: Investigar aspectos metodológicos do um método para estimar o consumo habitual de alimentos, bem como sua aplicação em estudo na população. Métodos: Inicialmente, utilizando amostra do National Health and Nutrition Examination Survey 2007-2008, foram estimadas distribuição do consumo habitual de vegetais verdes escuros a partir de amostras de diferentes tamanhos e diferentes percentuais de indivíduos com dois recordatórios de 24 horas (R24h). Posteriormente, foram utilizados dados do Inquérito de Saúde de São Paulo, estudo transversal, de base populacional, (n=716), cujos participantes responderam dois R24 horas e um questionário de freqüência alimentar (QFA). Verificou-se o efeito da inclusão do QFA como co-variável na melhora da predição do modelo do consumo de alimentos. Por fim, utilizando modelagem bivariada, estimou-se a ingestão habitual de porções de grupos alimentares recomendado pelo Guia Alimentar para População Brasileira, e calculou-se o percentual de indivíduo que não atingiram a recomendação. Para os três propósitos, a ingestão habitual foi estimada pelo método do National Cancer Institute. Resultados: A precisão das estimativas de consumo habitual reduziu quando menores taxas de replicação foram utilizadas. Para estudos que objetivam o cálculo da média ou o percentual de indivíduos com consumo abaixo de um dado ponto de corte, a redução da precisão pode não representar um importante viés. Para alimentos com elevado percentual de não consumidores, a inclusão simultânea do QFA e de uma variável indicadora de consumo resultou em melhor predição, ressaltando que a inclusão de somente a variável indicadora já se mostrou satisfatória. O percentual de indivíduos com consumo habitual das porções dos grupos de alimentos abaixo do recomendado pelo Guia Alimentar foi: 88 por cento para cereais, tubérculos, raízes e derivados; 43 por cento para feijões; 11 por cento para carnes e ovos; 100 por cento para leite e derivados; 95 por cento para frutas e sucos de frutas naturais; 72 por cento para legumes e verduras; 83 por cento para açúcares e doces; e 93 por cento para óleos, gorduras e sementes oleaginosas / Introduction: The estimation of the habitual food intake requires the use of proper statistical techniques. For some foods, it is possible to find consumption equal to zero in one or several days, even to individuals who usually consume them. Then, methods must be able to deal with two concerns: the zero-inflated distribution; and the correlation between probability and amount of consumption. Objective: To investigate methodological issues of a method to estimate habitual food intake to use it to analyze dietary data from a population. Methods: First, using the National Health and Nutrition Examination Survey 2007-2008, it was estimated the habitual dark green vegetable intake from a samples with different size and percentual of individuals with two 24-hour recall (24hr). After, it was used a subsample of the Inquerito de Saúde de São Paulo, a population-based cross-sectional study (n=716), in which the participants answered two 24hr and one food frequency questionnaire (FFQ). It was verified the effect of the FFQ as covariate on the prediction improvement of the models to estimate habitual food intake. Finally, using a bivariate modeling, it was estimated the habitual serving consumption of the food groups with recommendation of consumption in the Brazilian Food Guide. The percentual of individual who did not meet the recommendations were calculated as well. To all purposes, the habitual food consumption was estimated using the National Cancer Institute method. Results: The precision of the usual intake estimates decreases when low replication rates are used. For studies that aim to estimate the average or the percentual of individual with consumption bellow the cut-offs, the loss of precision may not represent an important bias. Considering foods with moderate to high percentual of non consumers, the simultaneously inclusion of the FFQ and a indicator of consumption variable (consume yes or not) was enough. The percentual of individuals with consumption bellow the recomandation were: 88 per cent for cereals, tubers and roots; 43 per cent for beans; 95 per cent for fruits, including fresh juices; 72 per cent for vegetables; 100 per cent for milk and dairy products; 11 per cent for meat and egg; 93 per cent for oils, fats and oil seeds; and 83 per cent for sugar and sweets
30

Olanzapine-induced Weight Gain: An Animal Model

Mann, Stephen Wallace 15 February 2010 (has links)
Introduction: Using an animal model, we examined weight gain in rats exposed to olanzapine, as well as whether increased weight was associated with food intake, visceral fat and/or locomotion. Methods: Sprague-Dawley rats were chronically treated with olanzapine while being offered diets including standard chow, a high fat (60% fat) diet, and a high fat/high carbohydrate (42% fat; 42.7% carbohydrate) diet. Body weight, food intake, visceral fat and locomotor activity were measured. Results: Our findings related to weight gain are in line with other reports indicating that while olanzapine-induced weight gain can be observed, it does not mirror what is observed in humans on two levels: (i) it is not of the same magnitude, and (ii) it is more gender specific i.e., females greater than males. Conclusions: These data confirm that chronic treatment with olanzapine has varying effects on weight gain, food intake, visceral fat and locomotor activity.

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