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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.
61

Neural Responses to Food Pictures and Their Association with Dietary Intake

Christenson, Edward 01 December 2012 (has links) (PDF)
BACKGROUND: Food-related visual cues may affect eating behavior and energy intake. The purpose of this study was to determine the neural response to pictures of food and whether or not the neural responses were associated with energy intake. METHODS: Using a cross-sectional design, 60 adults participated in this study. Each participant reported to the laboratory in a fasted state, were fitted with a 128-electrode electroencephalogram (EEG) net, and were shown pictures grouped into three categories: high-calorie foods, low-calorie foods, and distractor pictures. These pictures were shown in random order. Furthermore, participants were shown these pictures in one passive condition and two active conditions (also in random order). The passive condition required participants to view pictures in a relaxed state while neural responses were recorded. The active conditions required participants to be actively engaged with the picture by pressing or withholding a specified button on a keyboard (go/no go task). The active conditions included only high- and low-calorie foods. Event Related Potentials (ERP) of interest were the N2, P300, and late positive potential (LPP). The National Cancer Institute's Automated Self-administered 24-hour Dietary Recall (ASA24) was used to assess energy and macronutrient intake. RESULTS: The N2 amplitude, when amplitude for high-calorie pictures is subtracted from the amplitude of low-calorie pictures, was significantly different for each active condition (F = 41.23; p < 0.0001). However, neural responses to picture-type for the N2, P300 and LPP were not different (p > 0.05). The difference in N2 amplitude, for the high-calorie no go condition that results from the amplitude for low and high-calorie pictures being subtracted from each other, was significantly associated with carbohydrate intake (r = -0.263) and significantly predicted carbohydrate intake (regression coefficient = -56.821; p = 0.043) but not energy, fat, or protein intake (p > 0.05). Neither the P300 nor the LPP was correlated with or predicted energy and macronutrient intake (p > 0.05). CONCLUSION: The N2 differentiates depending on the no go stimulus. The difference in N2 amplitude, for the high-calorie no go condition, may be an index of carbohydrate intake. The P300 and LPP do not appear to differentiate between pictures of high- and low-calorie foods, nor do they correlate with energy or macronutrient intake.
62

A Randomized Controlled Trial to Study the Effects of Breakfast on Energy Intake, Physical Activity, and Body Fat in Women

LeCheminant, Gabrielle Marie 01 December 2014 (has links) (PDF)
PURPOSE: The purpose of this study was to determine the effects of eating breakfast on energy intake, physical activity, body weight, and body fat in women who were nonhabitual breakfast eaters over a one-month period. METHODS: We tested 49 premenopausal, nonhabitual breakfast-eating women to compare the effects of eating breakfast versus not eating breakfast. Each participant was randomized to one of two conditions: breakfast or no breakfast. Breakfast eaters were required to eat within an hour and a half of awakening and had to be finished eating their breakfast meal by 8:30 A.M. Non-breakfast eaters were defined as not consuming a snack or meal (with the exception of water) until after 11:30 A.M. Participants assigned to the breakfast condition consumed at least 15% of their daily energy requirement for breakfast. Weight and body fat were assessed at the baseline and after one month of intervention. Body fat was measured by dual-energy x-ray absorptiometry (DXA). Participants completed seven 24-hour recalls to assess dietary intake during the intervention. Physical activity was measured by accelerometry for 32 consecutive days. RESULTS: On average, the participants randomized to eat breakfast consumed 266 ± 496 (F = 12.81; P = 0.0043) more calories per day over the course of the study and weighed 0.6 ± 0.81 kg (F = 7.81; p = 0.0076) more at the end of the intervention. There was no observed caloric compensation at subsequent meals and no change in self-reported hunger or satiety. There was also no physical activity compensation with the addition of breakfast. CONCLUSION: The findings of our study showed that requiring non-breakfast eaters to eat breakfast resulted in higher caloric intake and weight gain. Future research should evaluate this relationship for a longer period of time to see if adding breakfast to the diet of women who generally do not eat breakfast results in adaptive behavior change over time.
63

Nutrient Density, Added Sugar, and Fiber Contents of Commercially Available Fruit Snacks in the United States from 2017 to 2022

Fu, Hao 01 September 2023 (has links) (PDF)
Fruit snacks have become a popular and convenient snacking choice and have the potential to contribute to a well-balanced diet. However, the nutritional quality of fruit snack products has not yet been studied in the fruit snack category. This study used the Mintel Global New Product Database to collect fruit snack product data launched in the United States from 2017 to 2022. Fruit snack products (n=2,405) are divided into nine product categories based on product characteristics. We assessed the nutrition profile by using a comprehensive score, Nutrient Rich Food (NRF6.4) model, and examining individual components (added sugar and fiber) among all fruit snack product categories. The results show that dry fruit has the highest nutrient density, fiber content, and lowest added sugar content per Reference Amount Customarily Consumed (RACC). Conversely, fruit-flavored snack has the least nutrient density, fiber content, and the highest added sugar content per RACC. Fruit puree, canned fruit with juice, and dried fruit currently are the only fruit snacks that meet the current recommendations set by the USDA Dietary Guidelines. Decreasing added sugar content, increasing fiber content, and enhancing sensory profile can be the directions for fruit snack product development in the industry.
64

THE RELATIONSHIP BETWEEN CHANGES IN BODY COMPOSITION, PHYSICAL ACTIVITY LEVELS, AND DIET OF 1st YEAR FEMALE STUDENTS AFTER ONE SEMESTER IN COLLEGE

Vystejnova, Barbora 30 November 2006 (has links)
No description available.
65

Effects of chronic suboptimal energy intake on constant-load exercise in young women

Fritsch, LeaAnn Thompson 18 September 2008 (has links)
The physiologic and metabolic effects of chronic consumption of energy below recommended levels on constant-load exercise was studied in women age 19-24 years. Ten controls (average caloric intake ~ 35 kcal/kg body weight) and 10 subjects with suboptimal energy intake (average caloric intake - 25 kcal/kg body weight) were matched for age, exercise caloric expenditure and percentage of HB-predicted RMR. Subjects (n=20) completed a maximal incremental cycle ergometer test and a 30-minute cycle ergometer test at 75 % of peak oxygen consumption. Although both groups presented a significant increase in ventilation (VE) over time of exercise, the rate of change in VE and end-exercise VE value was significantly greater, F (1 J 18) = 5.63, P < .05, for the suboptimal energy intake group than for the controls. Although not statistically significant (p = 0.454), heart rate (HR) tended to be continuously higher for the suboptimal energy intake group than the control group during the constant-load cycle test. Peripheral ratings of perceived exertion (RPE-L) also tended to be higher for the suboptimal energy intake group at the end of constant-load exercise, however, not significantly (p = 0.072). Two subjects in the suboptimal energy intake group failed to complete the 30-minute submaximal constant-load cycle test; one completed 15 minutes and the other 20 minutes. All subjects in the control group completed the entire submaximal constant-load test (30 minutes). These results suggest that women with chronic suboptimal energy intake have increased difficulty tolerating moderate intensity exercise for 30 minutes (an intensity and duration that mimics a typical exercise session). / Master of Science
66

Immune system status, select nutrient intakes, and micronutrient status in young women with a chronic suboptimal energy intake

Wagner, Tracey L. 29 August 2008 (has links)
Little is known regarding the nutrition and health implications of chronic dieting in college-women. Therefore, this study was conducted to determine nutrient intakes, zinc status, and immune system status in 19-24 year-old college women consuming different energy intakes. A suboptimal group (SG) (n=9), with a chronic suboptimal energy intake of ≤70% of the RDA, was matched for partial energy output to a control group (CG) (n=9), with a chronic optimal energy intake of ≥90% of the RDA. Zinc status was assessed using plasma zinc, red blood cell (RBC) zinc, and RBC fragility. Immune system status was assessed using IgG, IgM, C3, % T cell, and % lymphocyte. The SG consumed significantly lower intakes of macronutrients and several micronutrients than the CG (p<.05). Nutrient intakes in the SG, ≤70% of the RDA, were energy, carbohydrate, fat, vitamin D, calcium, iron, zinc, and copper; but only vitamin D and zinc in the CG. Zinc status and immune system status were not significantly different between the two groups (p>.05). No correlations were found between zinc intake and the zinc status markers, suggesting that the markers were not sensitive indicators. In the SG only, significant positive correlations were found between intakes of energy, macronutrients, and zinc, and one or more of the immune components (p<.05). These findings suggest that although the apparent immune system status was not altered by a suboptimal energy intake, in an inadequate energy intake, immune system status reflected nutrient intakes. / Master of Science
67

Effect of acute exercise and diet manipulations on postprandial metabolism in boys and girls

Thackray, Alice E. January 2014 (has links)
Elevated postprandial triacylglycerol concentrations ([TAG]) are associated with the development and progression of atherosclerosis, and are established as an independent risk factor for future cardiovascular disease. Considering the majority of the daytime is spent in a postprandial state typically, and the paediatric origins of atherosclerosis are well established, lifestyle interventions including manipulations of exercise energy expenditure and dietary energy intake should be initiated early in life. Therefore, this thesis aimed to investigate the postprandial metabolic responses to different exercise and energy intake manipulations in boys and girls, with concentrations of circulating TAG representing the primary outcome of interest. To achieve this, a total of 60 healthy 11 to 13 year old boys and girls were recruited into five experimental studies. The first experimental study (Chapter 4) demonstrated that a single session of high-intensity interval running (HIIR) involving 10 x 1 min intervals at 100% maximal aerobic speed (MAS) resulted in a moderate reduction in postprandial plasma [TAG] in 11 to 12 year old boys. In the second experimental study (Chapter 5), immediate replacement of the moderate-intensity exercise-induced energy deficit negated the reduction in postprandial plasma [TAG] in 11 to 13 year old boys. Furthermore, an exercise-induced energy deficit was required to promote an increase in whole-body fat oxidation. The importance of the associated energy deficit was explored further in Chapter 6, which demonstrated that a moderate-intensity exercise-induced energy deficit elicited a greater reduction in postprandial plasma [TAG] than an isoenergetic diet-induced energy deficit in 11 to 13 year old girls (21% vs. 10% respectively). Chapter 7 compared the effect of 10 x 1 min interval runs at 100% MAS (HIIR) and 5 x 1 min interval runs at 100% MAS combined with a mild reduction in habitual energy intake by 0.82 MJ (195 kcal; HIIR-ER) on postprandial metabolism in 11 to 13 year old girls. Acute manipulations of low volume HIIR and ER reduced postprandial plasma [TAG] and increased resting whole-body fat oxidation, with the magnitude of effect marginally, although not meaningfully, greater following HIIR than HIIR-ER. The final experimental chapter (Chapter 8) compared directly healthy 11 to 13 year old boys and girls postprandial TAG responses to acute HIIR. Although postprandial plasma [TAG] was substantially lower in boys compared with girls, the magnitude of reduction following HIIR was similar between the sexes (11% vs. 10% respectively). Collectively, these studies demonstrate the efficacy of acute moderate- and high-intensity exercise, and to a lesser extent energy-intake restriction, to reduce postprandial plasma [TAG] and increase resting whole-body fat oxidation in boys and girls. Furthermore, the beneficial effect of exercise on postprandial metabolism appears dependent on the maintenance of the associated energy deficit. These lifestyle interventions have the potential to provide a practical, effective and engaging stimulus to promote a healthier cardiovascular risk profile in early adolescence.
68

Densidade energética da dieta e ingestão energética total segundo consumo de adoçantes e/ou alimentos processados com adoçantes / Dietary energy density and total energy intake according to the consumption of sweeteners and/or processed foods with sweeteners

Tavares, Carolina Faria 26 August 2013 (has links)
Introdução. O consumo de açúcares aumentou consideravelmente nas últimas décadas, bem como a incidência e a prevalência da obesidade, gerando a elaboração de recomendações para moderá-lo. Os açúcares contribuem para a palatabilidade dos alimentos, podendo também aumentar sua densidade energética (DE), outro fator de risco para obesidade. Uma alternativa seria a substituição por adoçantes não calóricos, que também aumentam a palatabilidade dos alimentos, porém são isentos calorias. No entanto, ainda não existe consenso a respeito das implicações desta substituição principalmente na redução da ingestão energética e do peso corporal. Objetivo. Identificar a DE da dieta, a ingestão energética total e de macronutrientes, segundo consumo de adoçantes e/ou alimentos processados com adoçantes por adultos e idosos. Métodos. Estudo transversal, no qual foram coletados dados de sexo; idade; peso e estatura, para cálculo do IMC; consumo de adoçantes, por questionário adaptado e pelo recordatório de 24 horas, foram calculadas as médias de DE, de ingestão energética total e de macronutrientes. Para verificar associação entre variáveis independentes (idade, sexo, IMC, uso de adoçantes não calóricos) com a dependente \"classificação da DE foi realizada regressão logística, considerando dietas com alta DE aquelas com 1,5 Kcal/g ou mais. Para comparação das médias de ingestão energética e de macronutrientes, entre usuários de adoçantes e não usuários, foi utilizado o Teste t de Student (p 0,05) pelo Stata 10.0. Resultados. Participaram do estudo 168 indivíduos, com idade média de 54,8 anos (DP = 14,9 anos), sendo 84,5 por cento do sexo feminino, 67,9 por cento com sobrepeso ou obesidade e 44,1 por cento usuários de adoçantes. A média da DE das dietas de usuários de adoçantes foi 1,15 Kcal/g (IC 95 por cento [1,11; 1,19]), e de não usuários 1,28 Kcal/g (IC 95 por cento [1,23; 1,33]). Para regressão logística, as variáveis contínuas, idade e IMC, foram categorizadas, porém esta última não permaneceu no modelo final (p > 0,10). Apesar de não significativo, a variável sexo permaneceu no modelo como ajuste. A classificação da idade (p = 0,042) e o uso de adoçantes (p = 0,002) apresentaram associação com os menores valores de DE. Não foi encontrada diferença nas médias de ingestão energética e de macronutrientes entre os grupos. Conclusão. Uso de adoçantes se associou com menores valores de DE, mas não houve diferença no consumo energético total e de macronutrientes entre grupos / The consumption of sugar has increased considerably in recent decades, as well as the incidence and prevalence of obesity, leading the development of recommendations to moderate this consumption. Sugars contribute to the palatability of food, but may also increase their energy density (ED), which is an important obesitys risk factor. An alternative would be replacing sugar by non-caloric sweeteners, which increase the palatability of foods, but with free calories. However, the implications of this substitution in reducing energy intake and body weight are controversial. Objective. Identify the ED of diets, the total energy intake and macronutrient consumption according to the consumption of sweeteners and/or processed foods with sweeteners by adults and elderly. Methods. A cross sectional study, that collected data on gender, age, weight and height, to calculate BMI, consumption of non-caloric sweeteners, by questionnaire and with data from 24-hour recall, were calculated the average of ED, total energy intake and total macronutrient intake. Logistic regression was performed to assess the association between independent variables (age, gender, BMI, use of non-caloric sweeteners) and the dependent classification of ED, considering diets with high ED those with 1.5 kcal/g or more. To compare the means of total energy intake and total macronutrient intake, among noncaloric sweeteners users and nonusers, was used the Students t test (p 0.05) by Stata 10.0. Results. Were collected data form 168 individuals, with an average age of 54.8 years (SD = 14.9 years), 84.5 per cent female, 67.9 per cent overweight or obese and 44.1 per cent users of sweeteners. The mean of ED diets of non-caloric sweeteners users was 1.15 kcal/g (CI 95 per cent [1.11; 1.19]), and 1.28 Kcal/g (CI 95 per cent [1.23; 1.33]) for non-users. For logistic regression the continuous variables, BMI and age, were categorized, but the former did not remained in the final model. Although the variable gender was not significant it remained in the model for adjustment. The classification of age (p = 0.042) and the use of sweeteners (p = 0.002) were associated with lower values of ED. No difference was found in the means of total energy intake and total macronutrient intake between the groups. Conclusion. The use of sweeteners was associated with lower values of ED, but there was no difference in the means of total energy intake and total macronutrient intake between the groups
69

Acute effects of exercise on appetite, food intake and circulating concentrations of gastrointestinal hormones

Deighton, Kevin January 2013 (has links)
Recent years have witnessed significant research into the acute effects of exercise on appetite, energy intake and gut hormone responses. The experiments in this thesis have further investigated this topic by examining the appetite, acylated ghrelin, peptide YY and energy intake responses to energy deficits induced via different exercise protocols and food restriction. To achieve this, 48 young healthy males (mean (SD): age 23 (3) years, body mass index 23.7 (2.7) kg.m-2, maximum oxygen uptake 52.9 (9.8) mL.kg 1.min-1) were recruited into four studies. In study one, 60 min of treadmill running at 70% of VO2 max did not stimulate any increases in appetite or daily energy intake regardless of whether the exercise was performed after breakfast or in the fasted state. In study two, six 30 s Wingate tests stimulated increases in appetite during the subsequent hours compared with 60 min of cycling at 68% of VO2 max. Differences in appetite appeared to be unrelated to changes in plasma acylated ghrelin concentrations and did not influence ad libitum energy intake. Subsequently, endurance exercise resulted in a significantly greater negative daily energy balance than sprint exercise due to a larger exercise energy expenditure. Study three revealed that appetite and energy intake did not differ from a resting control trial after either ten, 4 min cycling bouts at 85 90% of VO2 max separated by 2 min of rest or 60 min of constant cycling at 60% of VO2 max. This occurred despite elevated PYY3-36 concentrations during the hours after exercise. Finally, study four showed that an energy deficit of ~1475 kJ stimulated increases in appetite when induced via food restriction but not when achieved by an acute bout of exercise. This was associated with differences in plasma PYY3-36 concentrations but did not appear to be related to changes in circulating levels of acylated ghrelin and did not influence energy intake. This thesis has shown that appetite perceptions do not differ from a resting control trial during the hours after continuous endurance exercise. Alternatively, supramaximal cycling exercise and subtle reductions in food intake stimulated increases in appetite during the subsequent hours. Such increases in appetite do not appear to be related to changes in acylated ghrelin but may be influenced by plasma PYY3-36 concentrations. Despite differences in appetite, daily energy intake was unaffected by all interventions.
70

Densidade energética da dieta e ingestão energética total segundo consumo de adoçantes e/ou alimentos processados com adoçantes / Dietary energy density and total energy intake according to the consumption of sweeteners and/or processed foods with sweeteners

Carolina Faria Tavares 26 August 2013 (has links)
Introdução. O consumo de açúcares aumentou consideravelmente nas últimas décadas, bem como a incidência e a prevalência da obesidade, gerando a elaboração de recomendações para moderá-lo. Os açúcares contribuem para a palatabilidade dos alimentos, podendo também aumentar sua densidade energética (DE), outro fator de risco para obesidade. Uma alternativa seria a substituição por adoçantes não calóricos, que também aumentam a palatabilidade dos alimentos, porém são isentos calorias. No entanto, ainda não existe consenso a respeito das implicações desta substituição principalmente na redução da ingestão energética e do peso corporal. Objetivo. Identificar a DE da dieta, a ingestão energética total e de macronutrientes, segundo consumo de adoçantes e/ou alimentos processados com adoçantes por adultos e idosos. Métodos. Estudo transversal, no qual foram coletados dados de sexo; idade; peso e estatura, para cálculo do IMC; consumo de adoçantes, por questionário adaptado e pelo recordatório de 24 horas, foram calculadas as médias de DE, de ingestão energética total e de macronutrientes. Para verificar associação entre variáveis independentes (idade, sexo, IMC, uso de adoçantes não calóricos) com a dependente \"classificação da DE foi realizada regressão logística, considerando dietas com alta DE aquelas com 1,5 Kcal/g ou mais. Para comparação das médias de ingestão energética e de macronutrientes, entre usuários de adoçantes e não usuários, foi utilizado o Teste t de Student (p 0,05) pelo Stata 10.0. Resultados. Participaram do estudo 168 indivíduos, com idade média de 54,8 anos (DP = 14,9 anos), sendo 84,5 por cento do sexo feminino, 67,9 por cento com sobrepeso ou obesidade e 44,1 por cento usuários de adoçantes. A média da DE das dietas de usuários de adoçantes foi 1,15 Kcal/g (IC 95 por cento [1,11; 1,19]), e de não usuários 1,28 Kcal/g (IC 95 por cento [1,23; 1,33]). Para regressão logística, as variáveis contínuas, idade e IMC, foram categorizadas, porém esta última não permaneceu no modelo final (p > 0,10). Apesar de não significativo, a variável sexo permaneceu no modelo como ajuste. A classificação da idade (p = 0,042) e o uso de adoçantes (p = 0,002) apresentaram associação com os menores valores de DE. Não foi encontrada diferença nas médias de ingestão energética e de macronutrientes entre os grupos. Conclusão. Uso de adoçantes se associou com menores valores de DE, mas não houve diferença no consumo energético total e de macronutrientes entre grupos / The consumption of sugar has increased considerably in recent decades, as well as the incidence and prevalence of obesity, leading the development of recommendations to moderate this consumption. Sugars contribute to the palatability of food, but may also increase their energy density (ED), which is an important obesitys risk factor. An alternative would be replacing sugar by non-caloric sweeteners, which increase the palatability of foods, but with free calories. However, the implications of this substitution in reducing energy intake and body weight are controversial. Objective. Identify the ED of diets, the total energy intake and macronutrient consumption according to the consumption of sweeteners and/or processed foods with sweeteners by adults and elderly. Methods. A cross sectional study, that collected data on gender, age, weight and height, to calculate BMI, consumption of non-caloric sweeteners, by questionnaire and with data from 24-hour recall, were calculated the average of ED, total energy intake and total macronutrient intake. Logistic regression was performed to assess the association between independent variables (age, gender, BMI, use of non-caloric sweeteners) and the dependent classification of ED, considering diets with high ED those with 1.5 kcal/g or more. To compare the means of total energy intake and total macronutrient intake, among noncaloric sweeteners users and nonusers, was used the Students t test (p 0.05) by Stata 10.0. Results. Were collected data form 168 individuals, with an average age of 54.8 years (SD = 14.9 years), 84.5 per cent female, 67.9 per cent overweight or obese and 44.1 per cent users of sweeteners. The mean of ED diets of non-caloric sweeteners users was 1.15 kcal/g (CI 95 per cent [1.11; 1.19]), and 1.28 Kcal/g (CI 95 per cent [1.23; 1.33]) for non-users. For logistic regression the continuous variables, BMI and age, were categorized, but the former did not remained in the final model. Although the variable gender was not significant it remained in the model for adjustment. The classification of age (p = 0.042) and the use of sweeteners (p = 0.002) were associated with lower values of ED. No difference was found in the means of total energy intake and total macronutrient intake between the groups. Conclusion. The use of sweeteners was associated with lower values of ED, but there was no difference in the means of total energy intake and total macronutrient intake between the groups

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