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- Creators: Schumann, Robert, 1810-1856
Description
The body is capable of regulating hunger in several ways. Some of these hunger regulation methods are innate, such as genetics, and some, such as the responses to stress and to the smell of food, are innate but can be affected by body conditions such as BMI and physical activity. Further, some hunger regulation methods stem from learned behaviors originating from cultural pressures or parenting styles. These latter regulation methods for hunger can be grouped into the categories: emotion, environment, and physical. The factors that regulate hunger can also influence the incidence of disordered eating, such as eating in the absence of hunger (EAH). Eating in the absence of hunger can occur in one of two scenarios, continuous EAH or beginning EAH. College students are at a particularly high risk for EAH and weight gain due to stress, social pressures, and the constant availability of energy dense and nutrient poor food options. The purpose of this study is to validate a modified EAH-C survey in college students and to discover which of the three latent factors (emotion, environment, physical) best predicts continual and beginning EAH. To do so, a modified EAH-C survey, with additional demographic components, was administered to students at a major southwest university. This survey contained two questions, one each for continuing and beginning EAH, regarding 14 factors related to emotional, physical, or environmental reasons that may trigger EAH. The results from this study revealed that the continual and beginning EAH surveys displayed good internal consistency reliability. We found that for beginning and continuing EAH, although emotion is the strongest predictor of EAH, all three latent factors are significant predictors of EAH. In addition, we found that environmental factors had the greatest influence on an individual's likelihood to continue to eat in the absence of hunger. Due to statistical abnormalities and differing numbers of factors in each category, we were unable to determine which of the three factors exerted the greatest influence on an individual's likelihood to begin eating in the absence of hunger. These results can be utilized to develop educational tools aimed at reducing EAH in college students, and ultimately reducing the likelihood for unhealthy weight gain and health complications related to obesity.
ContributorsGoett, Taylor (Author) / Johnston, Carol (Thesis advisor) / Lee, Chong (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2013
Description
ABSTRACT The hormone leptin is an important regulator of body weight and energy balance, while nitric oxide (NO) produced in the blood vessels is beneficial for preventing disease-induced impaired vasodilation and hypertension. Elevations in the free radical superoxide can result in impaired vasodilation through scavenging of NO. Omega 3 is a polyunsaturated fatty acid that is beneficial at reducing body weight and in lowering many cardiovascular risk factors like atherosclerosis. The present study was designed to examine the change in plasma concentrations of leptin, nitric oxide, and the antioxidant superoxide dismutase in addition to examining the association between leptin and NO in healthy normal weight adult female subjects before and following omega 3 intakes. Participants were randomly assigned to either a fish oil group (600 mg per day) or a control group (1000 mg of coconut oil per day) for 8 weeks. Results showed no significant difference in the percent change of leptin over the 8 week supplementation period for either group (15.3±31.9 for fish oil group, 7.83±27 for control group; p=0.763). The percent change in NO was similarly not significantly altered in either group (-1.97±22 decline in fish oil group, 11.8±53.9 in control group; p=0.960). Likewise, the percent change in superoxide dismutase for each group was not significant following 8 weeks of supplementation (fish oil group: 11.94±20.94; control group: 11.8±53.9; p=0.362). The Pearson correlation co-efficient comparing the percent change of both leptin and NO was r2= -0.251 demonstrating a mildly negative, albeit insignificant, relationship between these factors. Together, these findings suggest that daily supplementation with 600 mg omega 3 in healthy females is not beneficial for improving these cardiovascular risk markers. Future studies in this area should include male subjects as well as overweight subjects with larger doses of fish oil that are equivalent to three or more servings per week. The importance of gender cannot be underestimated since estrogen has protective effects in the vasculature of females that may have masked any further protective effects of the fish oil. In addition, overweight individuals are often leptin-resistant and develop impaired vasodilation resulting from superoxide-mediated scavenging of nitric oxide. Therefore, the reported antioxidant and weight loss properties of omega 3 supplementation may greatly benefit overweight individuals.
ContributorsAlanbagy, Samer (Author) / Sweazea, Karen (Thesis advisor) / Johnston, Carol (Committee member) / Shepard, Christina (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2014
Description
ABSTRACT
Asthma is a high-stress, chronic medical condition; 1 in 12 adults in the United States combat the bronchoconstriction from asthma. However, there are very few strong studies indicating any alternative therapy for asthmatics, particularly following a cold incidence. Vitamin C has been proven to be effective for other high-stress populations, but the asthmatic population has not yet been trialed. This study examined the effectiveness of vitamin C supplementation during the cold season on cold incidence and asthmatic symptoms. Asthmatics, otherwise-healthy, who were non-smokers and non-athletes between the ages of 18 and 55 with low plasma vitamin C concentrations were separated by anthropometrics and vitamin C status into two groups: either vitamin C (500 mg vitamin C capsule consumed twice per day) or control (placebo capsule consumed twice per day). Subjects were instructed to complete the Wisconsin Upper Respiratory Symptom Survey-21 and a short asthma symptoms questionnaire daily along with a shortened vitamin C Food Frequency Questionnaire and physical activity questionnaire weekly for eight weeks. Blood samples were drawn at Week 0 (baseline), Week 4, and Week 8. Compliance was monitored through a calendar check sheet. The vitamin C levels of both groups increased from Week 0 to Week 4, but decreased in the vitamin C group at Week 8. The vitamin C group had a 19% decrease in plasma histamine while the control group had a 53% increase in plasma histamine at the end of the trial, but this was not statistically significant (p>0.05). Total symptoms recorded from WURSS-21 were 129.3±120.7 for the vitamin C and 271.0±293.9, but the difference was not statistically significant (p=0.724). Total asthma symptoms also slightly varied between the groups, but again was not statistically significant (p=0.154). These results were hindered by the low number of subjects recruited. Continued research in this study approach is necessary to definitively reject or accept the potential role of vitamin C in asthma and cold care.
Asthma is a high-stress, chronic medical condition; 1 in 12 adults in the United States combat the bronchoconstriction from asthma. However, there are very few strong studies indicating any alternative therapy for asthmatics, particularly following a cold incidence. Vitamin C has been proven to be effective for other high-stress populations, but the asthmatic population has not yet been trialed. This study examined the effectiveness of vitamin C supplementation during the cold season on cold incidence and asthmatic symptoms. Asthmatics, otherwise-healthy, who were non-smokers and non-athletes between the ages of 18 and 55 with low plasma vitamin C concentrations were separated by anthropometrics and vitamin C status into two groups: either vitamin C (500 mg vitamin C capsule consumed twice per day) or control (placebo capsule consumed twice per day). Subjects were instructed to complete the Wisconsin Upper Respiratory Symptom Survey-21 and a short asthma symptoms questionnaire daily along with a shortened vitamin C Food Frequency Questionnaire and physical activity questionnaire weekly for eight weeks. Blood samples were drawn at Week 0 (baseline), Week 4, and Week 8. Compliance was monitored through a calendar check sheet. The vitamin C levels of both groups increased from Week 0 to Week 4, but decreased in the vitamin C group at Week 8. The vitamin C group had a 19% decrease in plasma histamine while the control group had a 53% increase in plasma histamine at the end of the trial, but this was not statistically significant (p>0.05). Total symptoms recorded from WURSS-21 were 129.3±120.7 for the vitamin C and 271.0±293.9, but the difference was not statistically significant (p=0.724). Total asthma symptoms also slightly varied between the groups, but again was not statistically significant (p=0.154). These results were hindered by the low number of subjects recruited. Continued research in this study approach is necessary to definitively reject or accept the potential role of vitamin C in asthma and cold care.
ContributorsEarhart, Kathryn Michelle (Author) / Johnston, Carol (Thesis advisor) / Sweazea, Karen (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2015
Description
Long term high fat diets (HFD) are correlated with the development of diabetes
and kidney disease. However, the impact of short term high fat intake on the etiology of kidney disease has not been well-studied. Therefore, this study examined the impact of a six week HFD (60% fat) on kidney structure and function in young male Sprague-Dawley rats. Previous studies have shown that these animals develop indices of diabetes compared to rats fed a standard rodent chow (5% fat) for six weeks. The hypothesis of this study is that six weeks of HFD will lead to early stages of kidney disease as evidenced by morphological and functional changes in the kidney. Alterations in morphology were determined by measuring structural changes in the kidneys (changes in mass, fatty acid infiltration, and structural damage). Alterations in kidney function were measured by analyzing urinary biomarkers of oxidative RNA/DNA damage, renal tissue lipid peroxidation, urinary markers of impaired kidney function (urinary protein, creatinine, and hydrogen peroxide (H2O2)), markers of inflammation (tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6)), as well as cystatin C, a plasma biomarker of kidney function. The results of these studies determined that short term HFD intake is not sufficient to induce early stage kidney disease. Beyond increases in renal mass, there were no significant differences between the markers of renal structure and function in the HFD and standard rodent chow-fed rats.
and kidney disease. However, the impact of short term high fat intake on the etiology of kidney disease has not been well-studied. Therefore, this study examined the impact of a six week HFD (60% fat) on kidney structure and function in young male Sprague-Dawley rats. Previous studies have shown that these animals develop indices of diabetes compared to rats fed a standard rodent chow (5% fat) for six weeks. The hypothesis of this study is that six weeks of HFD will lead to early stages of kidney disease as evidenced by morphological and functional changes in the kidney. Alterations in morphology were determined by measuring structural changes in the kidneys (changes in mass, fatty acid infiltration, and structural damage). Alterations in kidney function were measured by analyzing urinary biomarkers of oxidative RNA/DNA damage, renal tissue lipid peroxidation, urinary markers of impaired kidney function (urinary protein, creatinine, and hydrogen peroxide (H2O2)), markers of inflammation (tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6)), as well as cystatin C, a plasma biomarker of kidney function. The results of these studies determined that short term HFD intake is not sufficient to induce early stage kidney disease. Beyond increases in renal mass, there were no significant differences between the markers of renal structure and function in the HFD and standard rodent chow-fed rats.
ContributorsCrinigan, Catherine (Author) / Sweazea, Karen (Thesis advisor) / Johnston, Carol (Committee member) / Mayol-Kreiser, Sandra (Committee member) / Arizona State University (Publisher)
Created2015
Description
Nut consumption, specifically almonds, have been shown to help maintain weight and influence disease risk factors in adult populations. Limited studies have been conducted examining the effect of a small dose of almonds on energy intake and body weight. The objective of this study was to determine the influence of pre-meal almond consumption on energy intake and weight in overweight and obese adults. In this study included 21, overweight or obese, participants who were considered healthy or had a controlled disease state. This 8-week parallel arm study, participants were randomized to consume an isocaloric amount of almonds, (1 oz) serving, or two (2 oz) cheese stick serving, 30 minutes before the dinner meal, 5 times per week. Anthropometric measurements including weight, waist circumference, and body fat percentage were recorded at baseline, week 1, 4, and 8. Measurement of energy intake was self-reported for two consecutive days at week 1, 4 and 8 using the ASA24 automated dietary program. The energy intake after 8 weeks of almond consumption was not significantly different when compared to the control group (p=0.965). In addition, body weight was not significantly reduced after 8 weeks of the almond intervention (p=0.562). Other parameters measured in this 8-week trial did not differ between the intervention and the control group. These data presented are underpowered and therefore inconclusive on the effects that 1 oz of almonds, in the diet, 5 per week has on energy intake and bodyweight.
ContributorsMcBride, Lindsey (Author) / Johnston, Carol (Thesis advisor) / Swan, Pamela (Committee member) / Mayol-Kreiser, Sandra (Committee member) / Arizona State University (Publisher)
Created2011
Description
The evaluation of nutritional status by dietary intake assessment is fundamental to nutrition research. Accurate assessment allows for health professional-moderated diet adjustment in order to promote disease prevention and management. However, dietary intake can be extremely challenging to measure properly as reliability and accuracy are essential. As technology use has become more prevalent in recent years, an assortment of online, web-based diet analysis methods have begun to emerge. Are these modern methods as accurate as the traditional methods? The aim of this study was to compare and contrast diet analyses from a feeding trial in which both subject-coded (using the Automated Self Administered 24 hour recall, or the ASA24) and investigator-coded (using the Food Processor diet analysis program) diet records were available. Sixty-four overweight (body mass index >27-40 kg/m2) members of a campus community between the ages of 20-45 were recruited for an 8-week parallel arm, randomized controlled trial to evaluate the impact of two different pre-dinner meal snacks on satiety, calories consumed, and contribution to modest weight loss. As part of the study requirements, participants completed 3-day food logs at four different times during the trial: pre-trial, and week 1, 4, and 8. Participants also entered their dietary information into the ASA24 website the day after the intake was recorded by hand. Nutrient intake values were compared between the ASA24 records and the handwritten food logs. All statistical analyses were performed using SPSS Statistical Analysis version 19.0; bivariate analyses and Spearman correlation analyses were utilized. Energy, macronutrient, and micronutrient intakes did correlate significantly between the two methodologies, though both under-reporting and over-reporting were found to exist. Carbohydrate and fiber intakes were under-reported by subjects; retinol, beta-carotene, and vitamin C amounts were over-reported. These results are consistent with previous findings in reporting differences and suggest that the ASA24 is a comparably accurate dietary tracking tool to the traditional diet record method.
ContributorsSchohl, Brooke (Author) / Johnston, Carol (Thesis advisor) / Mayol-Kreiser, Sandra (Committee member) / Wharton, Christopher (Christopher Mack), 1977- (Committee member) / Arizona State University (Publisher)
Created2012
Description
ABSTRACT This study evaluated the LoseIt Smart Phone app by Fit Now Inc. for nutritional quality among users during an 8 week behavioral modification weight loss protocol. All participants owned smart phones and were cluster randomized to either a control group using paper and pencil record keeping, a memo group using a memo function on their smart phones, or the LoseIt app group which was composed of the participants who owned iPhones. Thirty one participants completed the study protocol: 10 participants from the LoseIt app group, 10 participants from the memo group, and 11 participants from the paper and pencil group. Food records were analyzed using Food Processor by ESHA and the nutritional quality was scored using the Healthy Eating Index - 2005 (HEI-2005). Scores were compared using One-Way ANOVA with no significant changes in any category across all groups. Non-parametric statistics were then used to determine changes between combined memo and paper and pencil groups and the LoseIt app group as the memo and paper and pencil group received live counseling at biweekly intervals and the LoseIt group did not. No significant difference was found in HEI scores across all categories, however a trend was noted for total HEI score with higher scores among the memo and paper and pencil group participants p=0.091. Conclusion, no significant difference was detected between users of the smart phone app LoseIt and memo and paper and pencil groups. More research is needed to determine the impact of in-person counseling versus user feedback provided with the LoseIt smart phone app.
ContributorsCowan, David Kevin (Author) / Johnston, Carol (Thesis advisor) / Wharton, Christopher (Christopher Mack), 1977- (Committee member) / Mayol-Kreiser, Sandra (Committee member) / Arizona State University (Publisher)
Created2011
Description
Despite recent strides for awareness, treatment, and control of hypertension, prevalence remains high with estimates suggesting one third of Americans have hypertension. The hypotensive effects of potassium and magnesium have been known and administered in a clinical setting for nearly a century. The purpose of this study was to examine the effectiveness of taking a potassium/magnesium supplement to help reduce blood pressure in individuals with mildly-moderately elevated blood pressure. In this randomized, controlled crossover trial, potassium and magnesium supplementation was explored among healthy adults with mildly elevated blood pressure in Phoenix, Arizona. Subjects (n = 12) were randomly assigned to ingest either the treatment chewy bar (217 mg potassium/day; 70.8 mg magnesium/day) or a placebo chewy bar for four weeks. For the subsequent four weeks, subjects ingested the other corresponding chewy bar. Systolic (SBP), diastolic (DBP), and average blood pressure values were not significantly different between the two groups (p = 0.645, p = 0.464 and p = 0.939, respectively). Baseline mean blood pressure was 121.0/75.7 mm Hg. The 12 subjects (8 females, 4 males) had a mean age of 29.3 years old and a mean BMI of 26.2. After four weeks, the treatment group had a slightly higher SBP (118.3 ± 13.3 mm Hg) than the control group (116.5 ± 17.8 mm Hg); however, DBP was lower in the treatment group (71.7 ± 12.4 mm Hg) than the control group (73.0 ± 10.0 mm Hg). In conclusion, daily supplementation of potassium and magnesium (217.2 mg/day and 70.8 mg/day, respectively) did not significantly lower blood pressure in adults with mildly-moderately elevated blood pressure.
ContributorsPawloski, Jason (Author) / Johnston, Carol (Thesis advisor) / Vega-Lopez, Sonia (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2015
Description
ABSTRACT
Objective: This research examined the effectiveness of a weight loss diet incorporating high protein pasta and breakfast cereal products as compared to a weight loss diet using conventional versions of gluten-free pasta and breakfast cereal.
Design: In a 6-week parallel-arm food trial (representing the first phase of a 12-week cross-over trial), 26 overweight and obese (Mean BMI 43.1 ± 12.4 kg/m²) participants, free of related comorbidities, were randomly assigned to the Zone diet (~29% energy intake from protein) or a control diet (~9% energy from protein). Participants were included in the trial if they satisfied the criteria for elevated risk for metabolic syndrome (top half of the TG/HDL ratios of all who were tested). Participants were instructed to eat prepared meals (total of 7 cereal packets and 14 pasta meals weekly) that included patented food technologies for the Zone diet and commercially available gluten-free rice pasta and a conventional name brand boxed cereal for the control diet. Body composition was measured with a bioelectrical impedance scale at weeks 1, and 6. Food records and diet adherence were recorded daily by the participants.
Results: Both the Zone and control diets resulted in significant weight loss (-2.9 ± 3.1 kg vs. -2.7 ± 2.6 kg respectively) over time (p = 0.03) but not between groups (p = 0.96). Although not statistically significant, the Zone diet appears to have influenced more weight loss at trial weeks 3, 4, and 5 (p = 0.46) than the control diet. The change in FFM was significant (p = 0.02) between the Zone and control groups (1.4 ± 3.6 kg vs. -0.6 ± 1.5 kg respectively) at week-6. Study adherence did not differ significantly between diet groups (p = 0.53).
Conclusions: Energy-restricted diets are effective for short-term weight loss and high protein intake appears to promote protein sparing and preservation of FFM during weight loss. The macronutrient profile of the diet does not appear to influence calorie intake, but it does appear to influence the quality of weight loss. Other measures of body composition and overall health outcomes should be examined by future studies to appropriately identify the potential health effects between these diet types.
Objective: This research examined the effectiveness of a weight loss diet incorporating high protein pasta and breakfast cereal products as compared to a weight loss diet using conventional versions of gluten-free pasta and breakfast cereal.
Design: In a 6-week parallel-arm food trial (representing the first phase of a 12-week cross-over trial), 26 overweight and obese (Mean BMI 43.1 ± 12.4 kg/m²) participants, free of related comorbidities, were randomly assigned to the Zone diet (~29% energy intake from protein) or a control diet (~9% energy from protein). Participants were included in the trial if they satisfied the criteria for elevated risk for metabolic syndrome (top half of the TG/HDL ratios of all who were tested). Participants were instructed to eat prepared meals (total of 7 cereal packets and 14 pasta meals weekly) that included patented food technologies for the Zone diet and commercially available gluten-free rice pasta and a conventional name brand boxed cereal for the control diet. Body composition was measured with a bioelectrical impedance scale at weeks 1, and 6. Food records and diet adherence were recorded daily by the participants.
Results: Both the Zone and control diets resulted in significant weight loss (-2.9 ± 3.1 kg vs. -2.7 ± 2.6 kg respectively) over time (p = 0.03) but not between groups (p = 0.96). Although not statistically significant, the Zone diet appears to have influenced more weight loss at trial weeks 3, 4, and 5 (p = 0.46) than the control diet. The change in FFM was significant (p = 0.02) between the Zone and control groups (1.4 ± 3.6 kg vs. -0.6 ± 1.5 kg respectively) at week-6. Study adherence did not differ significantly between diet groups (p = 0.53).
Conclusions: Energy-restricted diets are effective for short-term weight loss and high protein intake appears to promote protein sparing and preservation of FFM during weight loss. The macronutrient profile of the diet does not appear to influence calorie intake, but it does appear to influence the quality of weight loss. Other measures of body composition and overall health outcomes should be examined by future studies to appropriately identify the potential health effects between these diet types.
ContributorsJames, Andrew (Author) / Johnston, Carol (Thesis advisor) / Mayol-Kreiser, Sandra (Committee member) / Shepard, Christina (Committee member) / Arizona State University (Publisher)
Created2015
Description
To date, there have not been any studies in a human population that explore the potential of vinegar ingestion in reducing visceral fat, a common yet serious metabolic disease risk factor. However, previous research in animal models exhibit promising findings, showing that vinegar is effective at reducing visceral fat. This is thought to be due to the activation of AMPK (adenosine monophosphate protein kinase) by acetic acid, the active ingredient in vinegar. The purpose of this study was to identify if this potentially groundbreaking relationship exists in human subjects. Healthy, nonsmoking, sedentary adults between the ages 18-45 y and a waist circumference measurement greater than or equal to 33 inches for women and 38 inches for men were recruited for this study. Twenty-three participants completed this 8-week, parallel arm, randomized control trial that tested the efficacy of red wine vinegar consumption (2 tablespoons red wine vinegar, twice per day, before a meal; providing 3.6 g acetic acid) against a placebo (1 apple cider vinegar pill, twice per day, before a meal; providing 0.0225 g acetic acid) for 8 weeks. Participants were randomized into either the vinegar (VIN) or control (CON) group after being stratified by age, gender, waist circumference, and weight. Results found that the VIN group experienced a 2% decrease in visceral fat (cm3, quantified by a DXA scan), but this change did not differ significantly from that of the CON group (p=0.256). The VIN group also experienced a slight decrease in insulin compared to the CON group, but this change was not significantly different than the control change (p=0.125). However, the change in HOMA-IR trended downward in the VIN group (-16%) as compared to the CON group (+9%) (p=0.079) with a large effect size, 0.153. Other parameters did not show statistically significant results between the groups. Further research is indicated in order to examine the potential of vinegar to reduce visceral fat.
ContributorsBaker, Olivia (Author) / Johnston, Carol (Thesis advisor) / Mayol-Kreiser, Sandra (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2018