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Demographic Factors and Beverage Consumption Patterns: Health Literacy, Education, and Income LevelFerguson, Katherine E. 12 May 2011 (has links)
Over the past several decades, the prevalence of overweight and obesity has increased to 68% of American adults1. During this same time period, there has been an increase in sugar-sweetened beverage consumption. This increase in added sugar consumption, particularly from sugar-sweetened beverages, has been theorized as a possible contributor to the obesity epidemic2,3,4. Sugar-sweetened beverages are the number one source of added sugars in the American diet and organizations such as the American Heart Association have addressed this issue of added sugar consumption due to its association with negative health outcomes5. A variety of demographic factors have been linked to increased added sugar consumption6. Health literacy is another variable which may influence beverage consumption patterns, specifically sugar-sweetened beverage consumption. To date only one study has investigated this association, and the authors reported an inverse relationship between health literacy scores and sugar-sweetened beverage consumption7. Therefore, the purpose of this investigation was to determine what demographic variables serve as predictors of consumption of sugar-sweetened beverages, water, milk, and total beverage calories. This could allow for appropriate interventions to be developed targeting healthier beverage consumption patterns in specific sub-populations. / Master of Science
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Exploring health disparities in rural regions of Virginia: The impact of health literacy and social capitalBailey, Angela 14 January 2016 (has links)
In the United States, low-income, ethnic/racial minorities and rural populations are at increased risk for poorer health outcomes compared to higher income, non-minorities, and urban populations. Two key determinants that influence rural health disparities are health literacy and social capital. Health literacy can be described as an individual-level factor and defined as, "the degree to which individuals have the capacity to obtain, process, and understand the basic health information and services needed to make appropriate health decisions." Social capital is a concept that accounts for the role of collective social functioning and has been defined as, "the features of social structures, such as levels of interpersonal trust and norms of reciprocity and mutual aid" which act as resources for individuals to facilitate collective action." The overarching goal of this research is to explore factors influencing health disparities, including health literacy, social capital in two rural regions of Virginia.
The first study is embedded in Talking Health, a larger 2-arm RCT targeting adults in rural Southwest Virginia and examined participants' perceptions of and satisfaction with components of a behavioral intervention designed using health literacy concepts to decrease sugary beverage intake in rural, low-health literacy participants. The second study is also embedded in the Talking Health trial, yet focused on the maintenance of behavior 12-months after the intervention concluded. Guided by RE-AIM, this study examined the reach, effectiveness and implementation of a 12-month randomized extended care intervention aimed at enhancing long-term maintenance of behavior change and study retention when compared to a control condition. The last study is part of a larger telephone surveillance survey conducted in the Dan River Region located in south central Virginia. This study described current levels of social capital in the Dan River Region and examined the influence of social capital on FV consumption, physical activity, sugary beverage intake and BMI on a sample of rural and urban adults. / Ph. D.
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Validity and Reliability of the BEVQ-15 in Children and AdolescentsHill, Catelyn Elizabeth 25 June 2016 (has links)
The prevalence of children and adolescents who are considered overweight or obese has grown drastically in the United States. Childhood overweight and obesity is associated with serious long-term health consequences, including an increased risk for cardiovascular disease, type 2 diabetes, strokes, and different types of cancers. Added sugar intake (AS), in the form of sugar-sweetened beverages (SSB), may contribute to weight gain and obesity development in children and adolescents. Due to the negative health implications of SSB consumption, a valid and reliable brief beverage intake assessment tool is needed for children and adolescents to advance research in this area. The BEVQ-15 food frequency questionnaire has been validated as a tool to assess habitual beverage intake in adults. By validating this tool in youth, there will be a rapid, feasibly administered method to assess beverage intake in children and adolescents. The purpose of this investigation was to determine the comparative validity and test-retest reliability of the BEVQ-15 for assessing usual beverage intake in children and adolescents. Participants (n=326) completed four laboratory sessions, which included providing demographic information, assessment of height/weight, and four record-assisted 24 hour dietary recalls (24HR) from January 2014-September 2015. The BEVQ was completed at 2 sessions (BEVQ1, BEVQ2). Validity was assessed by comparing beverage intake from dietary recalls (24HR) to the BEVQ1; reliability was assessed by comparing BEVQ responses at two sessions (BEVQ1, BEVQ2). Data analysis included descriptive statistics, paired sample t-tests, independent sample t-tests, and chi-squared test, and one-way ANOVA tests. Comparisons of validity and reliability were also made within two subsets; children (aged 6-11) and adolescents (aged 12-18). In the full sample, self-reported water and total sugar-sweetened beverage intake (in fl oz and kcal) were not different between BEVQ1 and 24HR. Responses between BEVQ1 and BEVQ2 were not different in intake (fl oz) or energy (kcal) for water, milk, and total sugar-sweetened beverages. In children, milk and energy (kcal) for total beverages were not different between BEVQ1 and 24HR. No differences were reported between BEVQ1 and BEVQ2 across beverage categories. In adolescents, water and energy (kcal) for total-sugar sweetened beverages were not different between BEVQ1 and 24HR. No differences were reported between BEVQ1 and BEVQ2 with the exception of sweetened juice drinks and total beverages. Overall, these results demonstrate that the BEVQ-15 appears to be a valid and reliable tool to assess habitual water and total SSB intake in children and adolescents. This tool could further epidemiological and clinical research examining the impact of SSB intake, as well as intake of other beverages, on health. / Master of Science
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Exploring Cross-Sectional Relationships between Health Literacy, Dietary Intake, Physical Activity, and Anthropometric/Biological Variables among Residents in Southwest VirginiaWilburn, Grace Alexandra 16 May 2014 (has links)
BACKGROUND: Low health literacy and numeracy are significant problems facing the United States. Recent research focuses heavily on the role health literacy and numeracy play in perception of disease risk, health care costs, all-cause mortality, and access to care; however, there has been relativity little emphasis on the relationships between health literacy or numeracy with health promotion behaviors, such as nutrition or physical activity. As our nation continues to face challenges with the high prevalence of obesity and other chronic diseases, it is increasingly important to understand the role that health literacy and numeracy play in nutrition and physical activity behaviors, as well as in the prevalence and control of chronic disease.
PRIMARY AIMS: The proposed research is embedded within a larger randomized-control trial, Talking Health, which is a 2-arm behavioral trial targeting residents in eight counties in southwest Virginia with sugar-sweetened beverage (SSB) consumption as the primary outcome. The primary aims of this cross-sectional study, using baseline Talking Health data, are to 1) examine correlations among health literacy and numeracy measures, namely the Newest Vital Sign (NVS), separated by reading (NVS Reading) and math (NVS Math) scores, the Rapid Estimate of Adult Literacy in Medicine (REALM), and the Subjective Numeracy Scale (SNS); 2) explore the relationships between demographic factors and the NVS, REALM, and SNS scores; 3) determine the relationships between the NVS, REALM, and SNS and dietary quality [i.e. Health Eating Index (HEI) scores], physical activity behaviors, and anthropometric and biological variables (body mass index, blood pressure, fasting blood lipids, and fasting blood glucose); and 4) determine if NVS, REALM, and SNS scores predict metabolic syndrome (MetS), while controlling for relevant demographic factors.
METHODS: Eligibility requirements for the study include being 18 years of age or older, having reliable access to a telephone, drinking ≥200 kilocalories of SSB per day, and being a resident of Southwest Virginia. Using previously validated instruments and standardized data collection protocol, a variety of baseline variables was collected on 264 participants. Health literacy was measured using the NVS and REALM and health numeracy was measured using the SNS. Dietary intake was measured via three 24-hour dietary recalls and HEI scores were calculated. Physical activity behaviors were assessed using the Godin Leisure Time Exercise Questionnaire. Weight was measured using a calibrated digital Tanita scale (Model: 310GS), height was measured using a portable research-grade stadiometer, blood pressure measurements were made with an OMRON automated oscillometric device (Model: HEM-907XL), and fasting blood samples were obtained via a finger stick and the CardioChek PA system was used to assess blood glucose, cholesterol, and triglycerides. MetS scores were determined based on an adaptation of the National Cholesterol Education Program guidelines. Statistical analysis included descriptive statistics, simple correlations (Pearson bivariate), one-way ANOVAs, and regression models.
RESULTS: Of 264 enrolled participants (mean age 41.1 + 13.5 years; 92.0% Caucasian; 81.8% female; 30.6% > high school education; 42% > $15,000 annual income), 33.7% were classified as having a high probability of low health literacy or possibility of low health literacy as measured by the NVS, 19.7% had less than a high school reading level as measured by the REALM, and 45.4% had low health numeracy as measured by the SNS. Additionally, 78.8% were overweight or obese and 29.0% meet the criteria for metabolic syndrome. Nine of the ten correlations between the NVS Total, NVS Reading, NVS Math, REALM, and SNS were statistically significant (p < .01, two-tailed). NVS scores were found to be significantly different by age (F = 2.36, p = .05), race (F = 4.49, p = .03), education level (F = 20.97, p < .001), and income (F = 13.88, p < .001); while REALM scores were only significantly different by race (F = 3.74, p = .05), education level (F = 21.06, p < .001), and income (F = 6.80, p < .001). SNS scores were significantly different by gender (F = 12.40, p = .001), education level (F = 11.01, p < .001), and income (F = 14.45, p < .001). Only systolic blood pressure, diastolic blood pressure, and strength training activity was found to be significantly different by health literacy and/or numeracy level; however, when controlling for hypertension medication use and/or demographic variables, only the relationship between health literacy (i.e, NVS) and strength training activity remained significant (R2 = 0.09, p = .01). Finally, health literacy and numeracy were not found to be predictive of metabolic syndrome while controlling for demographic variables.
DISCUSSION: Although numerous demographic factors were related to baseline health literacy and numeracy levels, anthropometric/biological variables, physical activity behaviors, and diet quality did not differ by health literacy and health numeracy level, with the exception of systolic blood pressure and strength training activity. This research helps to fill the gaps in the literature surrounding the prevalence of health literacy, health numeracy, and health promoting behaviors and chronic disease among rural residents in medically underserved counties in southwest Virginia. While few cross-sectional relationships were found, future research from this RCT should examine if health literacy and health numeracy moderates or mediates intervention changes in anthropometric/biological variables, physical activity behaviors, diet quality, and metabolic syndrome scores. / Master of Science
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Application of The Theory of Planned Behavior in a Randomized Control Trial Targeting Sugar-Sweetened Beverage Intake and Physical Activity in Southwest VirginiaTyhurst, Maja 07 June 2015 (has links)
BACKGROUND: Health-related interventions informed by behavioral theory have been shown to be more effective in changing behaviors as compared to those that are not. The Theory of Planned Behavior (TPB) has been used to successfully predict and explain a variety of health related behaviors, including sugar-sweetened beverage (SSB) intake and physical activity (PA). The TPB assumes that behavioral intentions are the most important determinant of behavior. Intentions are the function of individual's attitudes toward the behavior (these evaluations can be positive or negative), subjective norms (social standards and expectations surrounding the behavior), and perceived behavioral control (perception of the ease with which the behavior can be performed). According to literature, behavioral intentions predict 20% - 40% of the variance in health behaviors with attitudes beings the strongest predictor of diet, and perceived behavioral control being the strongest predictor of physical activity related intentions. Excessive SSB consumption and inadequate PA have been highly associated with the obesity epidemic, and related comorbidities such as cardiovascular disease and type-2 diabetes. Understanding and targeting these behaviors through application of health behavior theories, such as the TPB, is important.
PRIMARY AIMS: This research is embedded within a larger 2-arm randomized-control trial, Talking Health, which targets residents in rural southwest Virginia. Guided by the TPB, the overall goal of the Talking Health trial is to determine the effectiveness of a 6-month intervention aimed at decreasing SSB intake (SIPsmartER) compared to a matched contact control aimed at increasing PA (MoveMore). Each condition includes three classes, one teach-back call, and 11 interactive voice response (IVR) calls. The primary aims of this secondary analysis of Talking Health are to 1) determine if single-item TPB indicators are correlated with multi-item TPB scales for SSB and PA; 2) examine how baseline TPB variables predict participation in the SIPsmartER and MoveMore; 3) determine how the IVR TPB variables assessed during IVR calls predict future SSB and PA behaviors reported in a subsequent IVR call; and 4) explore how TPB variables change over the course of the teach back and 11 IVR calls.
METHODS: Eligibility requirements included being 18 years of age or older, having reliable access to a telephone, drinking 200 kilocalories of SSB per day, and having no contraindications for moderate-intensity physical activity. The present research utilizes data from the baseline health assessment, class attendance and IVR and teach back calls completion data, as well as data collected in teach-back and 11 IVR calls. Multi-item TPB constructs for both SSB and PA behaviors were assessed at baseline (measured on a 7-point Likert scale). Each IVR call assessed self-reported past week behavior (ounces of SSB or minutes of PA) and four single-item TPB constructs including behavioral intentions, perceived behavioral control, instrumental attitudes, affective attitudes, and subjective norms. Participation was measured as the number out of 15 activities completed by participants (three classes, one teach back call, and 11 IVR calls). Statistical analysis included descriptive statistics, Chi square tests, independent T-tests, Pearson's correlations, Cronbach's α, and sequential multi-step regression models. Multiple data imputations were used to account for missing data.
RESULTS: Of the 301 participants, 81% were female and 93% were Caucasian. The mean age of participants was 48.8 ± 13.5. Additionally, 32% of participants completed high school education, 55% earned < $20,000 per year, 32% had a full time or part time job, and 33% were classified as low health literate. Single-item indicators for both SSB-TPB questions (r > 0.60) and PA-TPB questions (r > 0.69) were highly correlated with their multi-item scales. Baseline TPB variables did not predict the participation rates in either SIPsmartER (F=1.763, R2=0.057, P=0.124) or MoveMore (F=0.815, R2=0.028, P=0.541) conditions. Of the nine SIPsmartER IVR regression models, eight were significant, and the SSB-TPB variables predicted about 30% of the variance in SSB behavior. Of the nine MoveMore IVR regression models, all were significant, and the PA-TPB variables predicted about 20% of the variance in SSB behavior. In both conditions, the majority of variance was explained by behavioral intentions and the addition of other TPB variables (perceived behavioral control, instrumental attitudes, affective attitudes, and subjective norms) explained substantially less variance in the behaviors. There were no notable patterns of change in TPB variables over 11 IVR calls for either SIPsmartER or MoveMore participants.
DISCUSSION: Our findings show that single-item indicators can be used as reliable measures of the TPB constructs. The TPB model did not show significant predictive value when it comes to participation in SIPsmartER or MoveMore. On the other hand, our findings show that TPB model explained about 30% (SSB) and about 20% (PA) of variance in behavior. Although significant changes in IVR TPB variables were found between the two time points in several instances for both SSB and PA behavior, there were no patterns of change over time. Based on our findings, assessing behavioral intentions as the goal behavior in each IVR call may be the most useful application of the TPB. Other TPB variables can be assessed using single-item indicators. / Master of Science
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The Role of Individual and Organizational Health Literacy on Health Behaviors and Health OutcomesKruzliakova, Natalie Anne 23 April 2018 (has links)
Health literacy (HL) is defined as the degree to which individuals have the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions. Low HL has been associated with poorer self-reported health status, inability to manage chronic conditions, and less use of preventive services. More research is needed to explore the relationship between HL and sugar-sweetened beverage (SSB) intake and physical activity (PA). Although numerous HL interventions are evident in the literature, those that test HL as a moderator of effectiveness are lacking. Additionally, it has been recognized that systems-level HL efforts are necessary to lessen the burden of low HL. This dissertation addresses these needs with three unique studies that took place within the rural, medically underserved southwest Virginia region.
Study 1 was a secondary analysis that examined the relationship and responsiveness of the Stanford Leisure-Time Activity Categorical Item (L-Cat) and adapted Godin Leisure-Time Exercise Questionnaire (GLTEQ) and determined if baseline HL status moderated intervention effects. There was high agreement L-Cat and adapted GLTEQ for classifying individuals as meeting PA recommendations. Baseline HL status did not moderate change in L-Cat or adapted GLTEQ measures.
Study 2 was a secondary analysis that determined if 6-month change in SSB intake predicted 6-month change in body mass index (BMI), weight, and quality of life (QOL), and determined if HL moderated these relationships. The regression models for weight and QOL were not significant. The BMI model was significant. Six-month change in SSB intake, experimental condition, and age were significant predictors for the BMI model. As hypothesized, HL did not moderate relationships in any models.
Study 3 details a multilevel mixed-methods needs assessment and collaboratively developed organizational HL improvement plan within the Virginia Department of Health (VDH). Staff responses revealed about half reported doing well across HL domains (written communication, oral communication, self-management and empowerment, supportive systems). However, needs were observed across all domains, with most improvement needed in written communication domain. There were significant correlations between clients' HL status and their perceptions of VDHs' HL practices, indicating potential areas of improvement within VDH. / Ph. D. / Health literacy is defined as the degree to which individuals have the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions. Low health literacy has been associated with poorer self-reported health status, inability to manage chronic conditions, and less use of preventive services. More research is needed to explore the relationship between health literacy and sugar-sweetened beverage intake and physical activity. Specifically, interventions that test the moderation of health literacy (i.e., how health literacy affects the strength of a relationship) are needed. Additionally, it has been recognized that systems-level health literacy efforts are necessary to lessen the burden of low health literacy. This dissertation addresses these needs within the rural, medically underserved southwest Virginia region.
Study 1 aimed to test the utility of two physical activity measures (Stanford Leisure-Time Activity Categorical Item and adapted Godin Leisure-Time Exercise Questionnaire) with a population of varying health literacy status with hopes of coming closer to identifying pragmatic standardized assessment of and detection of clinically meaningful change in physical activity behaviors, and to determine if health literacy moderated this change. Study 2 expanded upon existing research that has determined that a decrease in sugar-sweetened beverage intake can result in a decrease in weight and body mass index (BMI), and improvement in quality of life (QOL) by aiming to determine if six-month change in SSB intake predicted six-month change in BMI, weight, and QOL and if health literacy moderated these relationships. Study 3 responds to national and state-wide initiatives by detailing the first use of the AHRQ Toolkit within a public health setting, Virginia Department of Health, to conduct a needs assessment and organizational health literacy improvement plan.
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Correlations between college students’ perception and goal of body weight, and their consumption behaviors of sugar-sweetened beverages and fried potatoesMardiyati, Nur January 1900 (has links)
Master of Science / Department of Human Nutrition / Tandalayo Kidd / Weiqun Wang / The number of overweight and obese college students in the United States has remained high, which could be related to the comfort food and beverages consumed. Sugar-sweetened beverages and fried potatoes are beverages and comfort food commonly consumed by college students. Furthermore, people’s behavior is affected by their perceptions and goals. Thus, this study aimed to assess the correlations between the perception, goal of body weight, and sugar-sweetened beverages and fried potatoes consumption behaviours of college students. A cross-sectional survey of 371 college students was conducted via a self-reporting questionnaire that included information related to sugar-sweetened beverages and fried potato consumption behavior in the past month. The involved students also described their body weight perception and future goal. Spearman correlation and Chi-square analyses were performed to examine the associations. There were significant associations (p<0.0001) between perception of body weight and goal of body weight, regular soda consumption and other sweetened beverage consumption, regular soda consumption and fried potato consumption, and other sweetened beverage consumption and fried potatoes consumption. In addition, there were significant correlations between goals of body weight and other sweetened beverage consumption (p=0.0370). These findings confirmed that perception of body weight was associated with goal of body weight and provided a significant importance for educational intervention to students on improving awareness of healthy body weight and eating.
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Potencial de utilização de análises de imagens e análises térmicas na cristalização de açúcares em leite condensadoSchumacher, Andrea Bordin January 2015 (has links)
O leite condensado é um produto amplamente estudado, sendo que os problemas de cristalização ao longo do processo constituem um dos aspectos de interesse quando se considera a produção em escala industrial. No entanto, não foram encontrados estudos que padronizassem técnicas de medida de tamanho de cristais e determinação da cristalinidade total em leite condensado. Este trabalho visa adaptar/desenvolver uma técnica especifica para análise de tamanho de cristais de lactose em leite condensado utilizando de microscopia juntamente com processamento e análise de imagem (software ImageJ). Além disso, acredita-se que o grau de cristalinidade possa se tornar um parâmetro de controle de qualidade em leites condensados, de modo que se propõe o estudo da viabilidade do uso de calorimetria exploratória diferencial para a determinação deste parâmetro. A técnica de processamento e análise de imagem mostrou-se confiável e permitiu realizar comparativo eficiente entre três marcas comerciais de leite condensado. Foi possível, mediante análise estatística, otimizar a metologia existente de preparação de lâminas visando reduzir o tempo e esforço da aplicação da técnica de acompanhamento de tamanho de cristais em ambiente industrial. Para o estudo da viabilidade do uso de analises térmicas para a determinação do grau de cristalinidade em leite condensado foram realizados estudos em térmicos simultâneos (DSC-TGA) e estudos de calorimetria exploratória diferencial em DSC e TMDSC em lactose p.a., sacarose p.a., misturas dos dois açúcares e em leite condensado. Na comparação das técnicas, observou-se que as três apresentam mesmo nível de precisão, porém exatidão distintas. A técnica de DSC foi a que permitiu obter maior definição dos picos identificados ao longo do termograma. Por outro lado, na técnica de MDSC, utilizando porta-amostras com furo, foi possível obter boa repetibilidade também com relação aos processos reversíveis e irreversíveis. A análise quantitativa de cristalinidade a partir de dados de calorimetria para misturas de sacarose e lactose é dificultada pela sobreposição dos picos dos diferentes processos térmicos sofridos pelos dois açúcares e pelo fato que foram encontrados indicativos de efeito sinergético na resposta térmica dos dois carboidratos quando em mistura. Assim como para as misturas de açúcares estudadas, não foi possível determinar o grau de cristalinidade em amostras de leite condensado. / Condensed milk is a widely studied product, given that the crystallization problems throughout the production process constitute one of the aspects of interest as far as the industrial scale production is concerned. However, studies that might enable standardized crystal size measurement techniques and crystallinity determination in condensed milk have not been found yet. This work aims at adapting/developing a specific technique for the analysis of lactose crystals size in condensed milk by using microscopy along with image analysis and processing (ImageJ software). Besides, it is believed that degree of crystallinity may become a quality control parameter in condensed milks, in such a way that it is proposed a viability study of the use of differential exploratory calorimetry for its determination. Processing technique and image analysis have demonstrated to be reliable and allowed to carry out efficient comparison between the three commercially available brands of condensed milk. It was possible, by means of statistical analysis, to optimize the existing thin plate preparation methodology with the aim of reducing time and strain of crystal size monitoring in industrial environment. In view of studying thermal analyses aiming at determining degree of crystallinity in condensed milk, studies in simultaneous thermal instruments (DSC-TGA) along with differential exploratory calorimetry in DSC and TMDSC were carried out in analytical grade sucrose and lactose, mixtures of both sugars and condensed milk. When comparing the techniques, one can observe that all three presented the same level of precision, but different accuracies. DSC technique was the one that allowed higher definition of identified peaks along the thermogram. On the other hand, in MDSC technique, using pierced sample holder, it was possible to obtain good repeatability even in regard to reversible and irreversible processes. Cristallinity quantitative analysis from calorimetry data for sucrose and lactose mixtures is hindered by the superposition of peaks from different thermal processes undergone by both sugars and by the fact that indicatives of synergistic effect were found in the thermal response of the above mentioned carbohydrates when mixed together. As it had occurred for the sugar mixtures studied, it was not possible to determine the degree of crystallinity in condensed milk samples.
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Potencial de utilização de análises de imagens e análises térmicas na cristalização de açúcares em leite condensadoSchumacher, Andrea Bordin January 2015 (has links)
O leite condensado é um produto amplamente estudado, sendo que os problemas de cristalização ao longo do processo constituem um dos aspectos de interesse quando se considera a produção em escala industrial. No entanto, não foram encontrados estudos que padronizassem técnicas de medida de tamanho de cristais e determinação da cristalinidade total em leite condensado. Este trabalho visa adaptar/desenvolver uma técnica especifica para análise de tamanho de cristais de lactose em leite condensado utilizando de microscopia juntamente com processamento e análise de imagem (software ImageJ). Além disso, acredita-se que o grau de cristalinidade possa se tornar um parâmetro de controle de qualidade em leites condensados, de modo que se propõe o estudo da viabilidade do uso de calorimetria exploratória diferencial para a determinação deste parâmetro. A técnica de processamento e análise de imagem mostrou-se confiável e permitiu realizar comparativo eficiente entre três marcas comerciais de leite condensado. Foi possível, mediante análise estatística, otimizar a metologia existente de preparação de lâminas visando reduzir o tempo e esforço da aplicação da técnica de acompanhamento de tamanho de cristais em ambiente industrial. Para o estudo da viabilidade do uso de analises térmicas para a determinação do grau de cristalinidade em leite condensado foram realizados estudos em térmicos simultâneos (DSC-TGA) e estudos de calorimetria exploratória diferencial em DSC e TMDSC em lactose p.a., sacarose p.a., misturas dos dois açúcares e em leite condensado. Na comparação das técnicas, observou-se que as três apresentam mesmo nível de precisão, porém exatidão distintas. A técnica de DSC foi a que permitiu obter maior definição dos picos identificados ao longo do termograma. Por outro lado, na técnica de MDSC, utilizando porta-amostras com furo, foi possível obter boa repetibilidade também com relação aos processos reversíveis e irreversíveis. A análise quantitativa de cristalinidade a partir de dados de calorimetria para misturas de sacarose e lactose é dificultada pela sobreposição dos picos dos diferentes processos térmicos sofridos pelos dois açúcares e pelo fato que foram encontrados indicativos de efeito sinergético na resposta térmica dos dois carboidratos quando em mistura. Assim como para as misturas de açúcares estudadas, não foi possível determinar o grau de cristalinidade em amostras de leite condensado. / Condensed milk is a widely studied product, given that the crystallization problems throughout the production process constitute one of the aspects of interest as far as the industrial scale production is concerned. However, studies that might enable standardized crystal size measurement techniques and crystallinity determination in condensed milk have not been found yet. This work aims at adapting/developing a specific technique for the analysis of lactose crystals size in condensed milk by using microscopy along with image analysis and processing (ImageJ software). Besides, it is believed that degree of crystallinity may become a quality control parameter in condensed milks, in such a way that it is proposed a viability study of the use of differential exploratory calorimetry for its determination. Processing technique and image analysis have demonstrated to be reliable and allowed to carry out efficient comparison between the three commercially available brands of condensed milk. It was possible, by means of statistical analysis, to optimize the existing thin plate preparation methodology with the aim of reducing time and strain of crystal size monitoring in industrial environment. In view of studying thermal analyses aiming at determining degree of crystallinity in condensed milk, studies in simultaneous thermal instruments (DSC-TGA) along with differential exploratory calorimetry in DSC and TMDSC were carried out in analytical grade sucrose and lactose, mixtures of both sugars and condensed milk. When comparing the techniques, one can observe that all three presented the same level of precision, but different accuracies. DSC technique was the one that allowed higher definition of identified peaks along the thermogram. On the other hand, in MDSC technique, using pierced sample holder, it was possible to obtain good repeatability even in regard to reversible and irreversible processes. Cristallinity quantitative analysis from calorimetry data for sucrose and lactose mixtures is hindered by the superposition of peaks from different thermal processes undergone by both sugars and by the fact that indicatives of synergistic effect were found in the thermal response of the above mentioned carbohydrates when mixed together. As it had occurred for the sugar mixtures studied, it was not possible to determine the degree of crystallinity in condensed milk samples.
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Consumo de bebidas açucaradas, obesidade e alterações metabólicas em adolescentes / Comsumption of sugary drinks, obesity and metabolic disorders in adolescentsAna Carolina Reiff e Vieira 25 March 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O sobrepeso e a obesidade na adolescência atingiram proporções epidêmicas na maior parte dos países industrializados bem como as alterações no metabolismo da glicose e dos triglicérides. As alterações no perfil do estado nutricional têm sido acompanhadas no aumento do consumo de bebidas açucaradas por adolescentes nos últimos anos. Algumas revisões sistemáticas recentes identificaram que o consumo de bebidas açucaradas associa-se ao ganho de peso entre a população em geral, inclusive em adolescentes e o efeito de tais bebidas vem sendo demonstrado não só na ocorrência do sobrepeso e obesidade, como também em associação com alterações metabólicas, hipertensão, esteatose e a ocorrência de diabetes tipo 2. Um efeito plausível do aumento no consumo de bebidas açucaradas seria a alteração nos triglicérides e no controle glicêmico, mas somente dois estudos seccionais, em adolescentes americanos, foram encontrados e ambos concluíram pelo efeito deletério do consumo de tais bebidas nesses parâmetros metabólicos. A presente tese teve como objetivo realizar uma revisão bibliográfica sobre consumo de bebidas açucaradas e alterações metabólicas em adolescentes. E avaliar essa associação em uma amostra probabilística de escolares da cidade de Niterói, RJ, com 610 adolescentes de 12 a 19 anos. Na revisão foram resgatados apenas dois artigos. No primeiro encontrou-se que para cada porção adicional de bebidas açucaradas consumidas por dia, houve aumento de 7% nos valores de HOMA-IR, aumento de 2,25mg/dL nas concentrações de triglicérides, diminuição de 0,73mg/dL de HDL-C nas meninas e redução de 0,35mg/dL de HDL-C nos meninos (p-valor<0,05). No segundo, foi observada uma tendência das bebidas açucaradas a explicar 2,4% da variância em AIR (β=-0,219, p-valor=0,07), sem diferença entre os sexos. Com relação às analises apresentadas com os adolescentes da cidade de Niterói, as meninas apresentaram, em média, menor consumo de bebidas açucaradas do que os meninos (222 vs. 262mL), sendo a prevalência de consumo diário acima de 75% para ambos os sexos. A ingestão total de calorias e carboidratos entre os meninos que consomem bebidas açucaradas foi maior comparada aos que não consomem (2.183 vs. 2.787kcal e 286,3 vs. 376,6g; respectivamente). No modelo final de regressão, o consumo de bebidas açucaradas apresentou uma associação positiva, apenas para triglicérides, nos meninos após ajuste por idade, IMC, energia e carboidrato, (=0,06; p=0,04). Em conclusão, tanto na revisão da literatura, quanto na análise dos dados, encontrou-se associação positiva entre o consumo de bebidas açucaradas e alterações metabólicas / Overweight and obesity among adolescents, as well as changes in the metabolism of glucose and triglycerides, have reached epidemic proportions in most industrialized countries. Changes in nutritional status have been followed by increased consumption of sugar beverages. Some systematic reviews have identified that the consumption of sugar beverages is associated with weight gain among general population, including adolescents. The effect of these beverages seems to influence not only the occurrence of overweight and obesity, but also in other diseases associated to obesity, as hypertension, hepatic steatosis and occurrence of type 2 diabetes. A reasonable effect of the increase in the sugar drink consumption would be the alteration in triglicérides and the glicêmico control, but two studies you only part, in American adolescents, had been found and both had concluded for the deleterious effect of the consumption of such drinks in these metabolic parameters.The present thesis had as objective to carry through a bibliographical revision on sugar drink consumption and metabolic alterations in adolescents. E to evaluate this association in pertaining to school a probabilist sample of the city of Niterói, Rio de Janeiro, with 610 adolescents of 12 the 19 years. In the revision only two articles had been rescued. In the first one one met that for each additional portion of sugar drinks consumed per day, it had increase of 7% in the values of HOMA-IR, increase of 2,25mg/dL in the concentrations of triglicérides, reduction of 0,73mg/dL of HDL-C in the girls and reduction of 0,35mg/dL of HDL-C in the boys (p-valor<0,05). In as, insulin was observed a trend of sugar drinks to explain 2.4% of the variance in AIR - Acute response (β=-0,219, p-valor=0,07), without difference between the sexos. With the adolescents of the city of Niterói, girls reported, on average, a lower sugar beverage consumption than boys (222 vs. 262mL), and the prevalence of daily consumption was grether than 75% for both sexes. Boys who drink sugar beverages presented higher energy and carbohydrates intakes than those who did not drink sweetened beverages (2.183 vs. 2.787kcal and 286.3 vs. 376.6 g, respectively). In the final regression model the consumption of sweetened beverages showed a positive association only for triglycerides in boys, after adjusting for age, BMI, energy and carbohydrate inatke, (= 0.06, p = 0.04). In conclusion, both the literature reviewed and the data analysis from adolescents of Niterói revealed a positive association between sugar beverage consumption and metabolic changes
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