Matching Items (30)
Filtering by
- All Subjects: Nutrition
- Creators: Sweazea, Karen
Description
Fish oil has been extensively researched for its protective effects on cognition. More recently, anthocyanins have also gained the attention of the medical community for their potential cognitive benefits. Maqui berries are one of the richest sources of anthocyanins known to science. While there are many randomized controlled trials (RCT) investigating the effects of fish oil and/or anthocyanins on cognition in various populations, there are no RCT that exclusively investigate the cognitive effects of these compounds in adults with Type 2 Diabetes (DM2). The purpose of this double-blinded, placebo-controlled RCT was to investigate the cognitive effects of maqui berry extract and fish oil supplements in adults with DM2 over the course of eight weeks. Adults with DM2 (n=29) were recruited by the researchers and randomized to either Group A or Group B. Because the study is ongoing, it is unknown which group received the intervention. The study used the Stroop Test and Trail Making Test (TMT) to measure cognition at baseline, 4 weeks, and 8 weeks. Anthropometrics, blood glucose, and hemoglobin A1C were also taken at these time points. Sixteen female participants were included in the final analysis. Neither group showed significant improvements in the cognitive tests. However, in Group A, the effect sizes were large for the change in Trail-Making Test A (0.167), Trail Making Test B (0.261), and Trail Making Test B minus A (0.296) scores. In Group A, the change in Trail Making Test B minus A scores between baseline and week 4, and between baseline and week 8 was significant (p=0.053) and produced a large effect size (0.258). The results suggest that fish oil and maqui berry extract may improve cognition in adults with DM2, but further studies with larger sample sizes are needed.
ContributorsDeimeke, Allyson (Author) / Johnston, Carol (Thesis advisor) / Grant, Shauna (Committee member) / Sweazea, Karen (Committee member) / Arizona State University (Publisher)
Created2023
Description
The glycation of plasma proteins leading to the production of advanced glycation end products (AGEs) and subsequent damage is a driving factor in the pathophysiology of diabetic complications. The overall research objective was to elucidate the mechanisms by which birds prevent protein glycation in the presence of naturally high plasma glucose concentrations. This was accomplished through the specific purpose of examining the impact of temperature and glucose concentration on the percent glycation of chicken serum albumin (CSA) in comparison to human serum albumin (HSA). Purified CSA and HSA solutions prepared at four different glucose concentrations (0 mM, 5.56 mM, 11.11 mM, and 22.22 mM) were incubated at three different temperatures (37.0°C, 39.8°C, and 41.4°C) on separate occasions for seven days with aliquots extracted on days 0, 3, and 7. Samples were analyzed by LC-ESI-MS for percent glycation of albumin. The statistically significant interaction between glucose concentration, temperature, albumin type, and time as determined by four-way repeated measures ANOVA (p = 0.032) indicated that all independent variables interacted to affect the mean percent glycation of albumin. As glucose concentration increased, the percent glycation of both HSA and CSA increased over time at all temperatures. In addition, HSA was glycated to a greater extent than CSA at the two higher glucose concentrations examined for all temperature conditions. Temperature differentially affected percent glycation of HSA and CSA wherein glycation increased with rising temperatures for HSA but not CSA. The results of this study suggest an inherent difference between the human and chicken albumin that contributes to the observed differences in glycation. Further research is needed to characterize this inherent difference in an effort to elucidate the mechanism by which birds protect plasma proteins from glycation. Future related work has the potential to lead to the development of novel therapies to prevent or reverse protein glycation prior to the formation of AGEs in humans, thus preventing the development and devastating effects of numerous diabetic complications.
ContributorsZuck, Jessica (Author) / Sweazea, Karen (Thesis advisor) / Johnston, Carol (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2016
Description
In the United States, two-thirds of adults are considered hypertensive orprehypertensive. In addition, chronic illness, such as hypertension, cardiovascular disease, and type II diabetes, results in $3.5 trillion in annual healthcare cost and is the primary cause of disability and death. As a result, many individuals seek cheaper and simpler alternatives to combat their conditions. In this exploratory analysis, a study assessing nitrate intake and its effects on vascular function in 39 young adult males was investigated for underlying metabolic variations through a liquid chromatography – mass spectrometry-based large-scale targeted metabolomics approach. A two-way repeated measures ANOVA was used, and 18 significant metabolites were discovered across the time, treatment, and time & treatment groups, including prostaglandin E2 (p<0.001), stearic acid (p=0.002), caprylic acid (p=0.016), pentadecanoic acid (p=0.027), and heptadecanoic acid (p=0.005). In addition, log-transformed principal component analysis and orthogonal partial least squares – discriminant analysis models demonstrated distinct separation among the treatment, control, and time variables. Moreover, pathway and enrichment analyses validated the effect of nitrate intake on the metabolite sets and its possible function in fatty acid oxidation. This better understanding of altered metabolic pathways may help explicate the benefits of nitrate on vascular function and reveal any unknown mechanisms of its supplementation.
ContributorsPatterson, Jeffrey (Author) / Gu, Haiwei (Thesis advisor) / Johnston, Carol (Committee member) / Sweazea, Karen (Committee member) / Arizona State University (Publisher)
Created2020
Description
ABSTRACT
Background. College students’ modifiable health behaviors, including unhealthful eating patterns, predispose them to risk for future cardiometabolic conditions.
Purpose. This novel 8-week randomized control parallel-arm study compared the effects of a daily 18-hour Time-Restricted Feeding protocol vs. an 8-hour fast on diet quality in college students. Secondary outcomes were resting morning blood pressure, biomarkers of glucose regulation, biomarkers of lipid metabolism, and anthropometric measures.
Methods. Eighteen healthy college students (age = 23 ± 4 years; BMI = 23.2 ± 2.3 kg/m2; MET = 58.8 ± 32.9 min/wk) completed this study. Participants were randomized to a daily 18-hour fasting protocol (Intervention; n = 8) or a daily 8-hour fasting protocol (Control; n = 10) for eight weeks. One ‘cheat’ day was permitted each week. Outcomes were measured at weeks 0 (baseline), 4, and 8. A non-parametric Mann Whitney U test was used to compare the week 4 change from baseline between groups. Statistical significance was set at p≤0.05.
Results. Diet quality (p = 0.030) and body weight (p = 0.016) improved from baseline to week 4 for the INV group in comparison to the CON group. The data suggest these improvements may be related to reductions in snacking frequency and increased breakfast consumption. Fasting blood glucose and hip circumference tended to improve for the INV group in comparison to the CON group (p = 0.091 and p = 0.100). However, saturated fat intake tended to increase in the INV group in comparison to the CON group (p = 0.064). Finally, there were no treatment differences between groups (p>0.05) for the 4-week change in total calories, dietary vitamin C, added sugars, resting systolic blood pressure, resting diastolic blood pressure, insulin, homeostatic model assessment for insulin resistance (HOMA-IR), low-density lipoprotein (LDL) cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, waist circumference, or MET.
Conclusion. These data, although preliminary, suggest that the 18-hour fasting protocol was effective for improving diet quality and reducing weight in comparison to the 8-hour fasting protocol in healthy college students. Future intervention trials will need to confirm these findings and determine the long-term relevance of these improvements for health outcomes.
Background. College students’ modifiable health behaviors, including unhealthful eating patterns, predispose them to risk for future cardiometabolic conditions.
Purpose. This novel 8-week randomized control parallel-arm study compared the effects of a daily 18-hour Time-Restricted Feeding protocol vs. an 8-hour fast on diet quality in college students. Secondary outcomes were resting morning blood pressure, biomarkers of glucose regulation, biomarkers of lipid metabolism, and anthropometric measures.
Methods. Eighteen healthy college students (age = 23 ± 4 years; BMI = 23.2 ± 2.3 kg/m2; MET = 58.8 ± 32.9 min/wk) completed this study. Participants were randomized to a daily 18-hour fasting protocol (Intervention; n = 8) or a daily 8-hour fasting protocol (Control; n = 10) for eight weeks. One ‘cheat’ day was permitted each week. Outcomes were measured at weeks 0 (baseline), 4, and 8. A non-parametric Mann Whitney U test was used to compare the week 4 change from baseline between groups. Statistical significance was set at p≤0.05.
Results. Diet quality (p = 0.030) and body weight (p = 0.016) improved from baseline to week 4 for the INV group in comparison to the CON group. The data suggest these improvements may be related to reductions in snacking frequency and increased breakfast consumption. Fasting blood glucose and hip circumference tended to improve for the INV group in comparison to the CON group (p = 0.091 and p = 0.100). However, saturated fat intake tended to increase in the INV group in comparison to the CON group (p = 0.064). Finally, there were no treatment differences between groups (p>0.05) for the 4-week change in total calories, dietary vitamin C, added sugars, resting systolic blood pressure, resting diastolic blood pressure, insulin, homeostatic model assessment for insulin resistance (HOMA-IR), low-density lipoprotein (LDL) cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, waist circumference, or MET.
Conclusion. These data, although preliminary, suggest that the 18-hour fasting protocol was effective for improving diet quality and reducing weight in comparison to the 8-hour fasting protocol in healthy college students. Future intervention trials will need to confirm these findings and determine the long-term relevance of these improvements for health outcomes.
ContributorsMayra, Selicia (Author) / Johnston, Carol (Thesis advisor) / Sears, Dorothy (Committee member) / Swan, Pamela (Committee member) / Sweazea, Karen (Committee member) / Wharton, Christopher (Christopher Mack), 1977- (Committee member) / Arizona State University (Publisher)
Created2020
Description
Background: Sugars form advanced glycation end products (AGEs) throughnatural metabolism and interactions with proteins, lipids, and nucleic acids, which accumulate in tissues and have been implicated in the etiology of chronic diseases. Due to the increased consumption of fructose and its high ability to form AGEs, a further understanding of this association is important to clarify the role of sugars in disease. The objective was to explore the association between usual fructose intake and serum levels of AGEs, as measured by carboxymethyl-lysine (CML) and methylglyoxal derivative (MG-H1), in healthy adults. Methods: This is a secondary analysis of a 15-d controlled feeding study (n=100) with participants consuming their usual diet conducted in the Phoenix metropolitan area. To assess participants’ usual diet, they were asked to complete two 7-d food diaries, which were then used to create custom 15-d menu plans administered during the feeding period. Forty participants were selected based on their 15-d mean total fructose intake for this analysis [top and bottom 20% of the sample distribution (median, IQR); high fructose (HF) n= 20, 72.6 (66.1-90.4) g/day, low fructose (LF) n= 20, 28.8 (22.7-32.2) g/day. Fasting serum collected five weeks after the feeding period were analyzed for CML and MG-H1, two well-established AGEs, using ELISA kits. A database of 549 common foods with known CML amounts was used to calculate exogenous CML intake based on daily food intake data. A general linear model was fitted to investigate the difference in serum CML and MG-H1 between LF and HF groups while adjusting for age, gender, BMI, and exogenous CML intake. Results: Participants in the HF group had significantly higher serum CML and lower MG-H1 levels compared to participants in the LF group (p=0.013 and p=0.002, respectively). This difference remained statistically significant after adjusting for covariates. Conclusions: The findings suggest that endogenous CML formation may be an explanation for the significantly higher serum CML levels in the HF compared to the LF group. This is significant in further understanding mechanisms of fructose intake and disease etiology and could have implications for at-risk populations consuming a high fructose diet.
ContributorsWeigand, Bethany (Author) / Tasevska, Natasha (Thesis advisor) / Sweazea, Karen (Committee member) / Lee, Chong (Committee member) / Arizona State University (Publisher)
Created2021
Description
There is a considerable amount of research stating that vegetarian diets have an alkalizing effect while the typical western diet is acid-forming. There is substantial evidence regarding the health benefits of an alkaline diet. Although vegetarian diets demonstrate the ability to foster these health benefits, many people are still not willing to adopt a completely vegetarian diet. PURPOSE: To evaluate the effect of following a vegan diet two or three days per week on acid-base balance in a healthy college student population aged 18-30. METHODS: In a one-week interventional design, 23 people were randomly assigned to follow a vegan diet 2 days per week (VEG2;n=7), 3 days per week(VEG3;n=8), or 7 days per week (VEG7;n=8). Urine pH and dietary PRAL were assessed in each group at baseline and after the one-week intervention. RESULTS: There was no significant difference in urinary pH between the three groups (p=0.12). The change in PRAL values after the dietary intervention was different between the 3 groups (p=0.03). CONCLUSION: Adherence to a vegan diet 2 or 3 days per week did not show a significant change in urinary pH or PRAL.
ContributorsCosgrove, Kelly (Author) / Johnston, Carol (Thesis advisor) / Sweazea, Karen (Committee member) / Mayol-Kreiser, Sandra (Committee member) / Arizona State University (Publisher)
Created2015
Description
Prior studies of Mourning Doves have observed no changed in glucose in response to either a high fat “chow” diet or a white bread diet. In the current feeding study, we fed doves an urban diet, high in carbohydrates, fat, and sodium, which is representative of typical American nutrition accessible to the avian population in an urbanized environment. Based on studies of other avian species that examined the effects of an urban diet on physiology, I hypothesized that doves fed an urban diet would have increased plasma glucose and sodium, which would promote an increase in plasma osmolality. This hypothesis was based on preliminary data that found birds fed an urban diet developed impaired vasodilation compared to seed diet control birds. Therefore, differences in plasma glucose, sodium, and osmolality were examined as increases may contribute to the impairment. Adult doves of both sexes were captured on the Arizona State University, Tempe campus. Doves were placed in two dietary groups: an urban diet consisting of a 50/50 ratio of French fries and nutritionally-balanced bird seed (n=7) and a control group of only the seed diet (n=6). Following the four-week diets, birds were euthanized, and cardiac plasma samples were collected from birds to measure glucose, sodium, and osmolality. There were no significant differences between the two study groups in plasma glucose concentration (p=0.445), sodium concentration (p=0.731), or osmolality (p=0.692). Sodium concentrations were signficantly more variable in birds consuming a seed diet than those that were provided the mixed French fry and seed diet (p=0.014). These results suggest that glucose, sodium, and osmolality likely do not contribute to the altered vasodilation of doves fed an urban diet and that such a diet may not be as detrimental to the doves health given their phenotypic flexibility.
ContributorsKayata, Lana (Author) / Sweazea, Karen (Thesis director) / Deviche, Pierre (Committee member) / Basile, Anthony (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Diabetes is the 7th leading cause of death globally. In 2018, 34.2 million Americans had type 2 diabetes. Many symptoms of diabetes are similar to those of scurvy or vitamin C deficiency. Vitamin C marginality and inadequacy are more prevalent in Type 2 Diabetes/prediabetes than with normal glucose tolerance. Intracellular vitamin C inadequacy is suspected due to competition between dehydroascorbic acid and glucose at GLUT 1 and 3 cellular receptors. Erythrocyte osmotic fragility is noted in Gulo -/- knockout mice unable to synthesize endogenous vitamin C. The ascorbate deficient red blood cells presented with low cytoskeletal B-spectrin, spherocyte appearance, and impaired deformability. This cross-sectional study investigated the relationships between diabetes status, erythrocyte osmotic fragility, and serum vitamin C status. Participants were aged 18-65, non-smoking, reported no unresolved health complications, and denied prior vitamin C supplementation. Those with T2D indicated diagnosis of >1 year. All participants provided written informed consent and the study was approved by the local Institutional Review Board in January 2021. Participants provided one fasted blood sample. Erythrocyte osmotic fragility was measured via UV/Vis spectrophotometry with various concentrations of sodium chloride (0.85% - 0.10%) to induce osmotic stress. In addition, plasma was extracted and mixed 1:1 with 10% (w/v) metaphosphoric acid in 2 mmol/L disodium EDTA and centrifuged. The supernatant was stored at -80°C until analysis with isocratic reverse-phase UV-HPLC separation.
Participant characteristics did not differ significantly between groups apart from age (p< 0.01) and HbA1c (p=0.002). Data are presented for adults with T2D (n=14; 36% female; 55.5±8.2 y; 31.5±9.0 kg/m2; HbA1c: 7.4±1.9%; plasma vitamin C: 36.0±12.2 uM) and without T2D (n=16; 69% female; 38.7±13.5 y; 26.8±6.6 kg/m2; A1c: 5.4±0.3%; plasma vitamin C: 34.8±10.9uM). Erythrocyte osmotic fragility was significantly elevated (+4.4% hemolysis) in adults without T2D at 0.35% saline (p=0.039). Greater VC status (>30 uM) was associated with lower hemolysis at 0.35% NaCl (p=0.031). Erythrocyte osmotic stability was linked to greater vitamin C intake at 0.20% saline in those without T2D (p =0.019).
In this pilot study, vitamin C status did not differ significantly by diabetes status. Vitamin C status was directly linked to erythrocyte osmotic stability in adults without T2D.
ContributorsLundy, Ciara Cheyanne (Author) / Johnston, Carol (Thesis advisor) / Sweazea, Karen (Committee member) / Alexon, Christy (Committee member) / Arizona State University (Publisher)
Created2022
Description
Background: Vegan and vegetarian diets have gained in popularity in recent years. Stated reasons for this include some possible health benefits and concerns of animal welfare. Though considered to be nutritionally adequate, questions remain over whether current protein recommendations of 0.8 g/kg/d are sufficient to maintain body processes and growth. Protein is unique in that it is the only macronutrient that contains nitrogen. Its status can be determined through nitrogen balance analysis of the urine if protein content of the diet is known. Nitrogen balance is considered the gold standard for determining protein intake requirements. A negative balance indicates a catabolic state, whereas a positive nitrogen balance is seen during anabolism. In healthy people, nitrogen equilibrium is desired under normal circumstances. This equilibrium reflects the net synthesis and breakdown of proteins. While nitrogen balance techniques have been used for decades, currently, there are no known studies measuring nitrogen balance and protein intake in strict vegans. Methods: Twenty vegan, inactive, male participants were recruited and received a 5-day eucaloric diet with a known protein content held constant at 0.8 g/kg/d. On day five, 24-hour urine was collected by participants and aliquoted for future analysis. Nitrogen content of the urine was determined through photometric assay and compared to the known nitrogen content of the diet to calculate nitrogen balance status.
Results: Mean absolute nitrogen balance (-1.38 ± 1.22 g/d, effect size = -1.13) was significantly lower than zero (equilibrium) (p < .001). Mean relative nitrogen balance (-18.60 ± 16.96 mg/kg/d, effect size = -1.10) was significantly lower than zero (p < .001). There were no correlations seen between nitrogen balance and age, years as vegan, or fat- free mass.
Conclusion: Consuming 0.8 g/kg/d of protein is insufficient to produce nitrogen balance in long-term vegans.
ContributorsBartholomae, Eric (Author) / Johnston, Carol (Thesis advisor) / Sweazea, Karen (Committee member) / Wharton, Christopher (Committee member) / Lee, Chong (Committee member) / Kressler, Jochen (Committee member) / Arizona State University (Publisher)
Created2022
Description
The Western Pattern diet has been characterized by having greater than 50 percent consumption coming from fat and sugar. This macronutrient allocation has been shown to have deleterious effects on endothelial function and metabolic markers of cardiovascular disease. Exercise has been shown to improve vascular reactivity and metabolic markers related to cardiovascular health. The objective of the study was to determine if exercise training can prevent the anticipated deleterious effects of a fat-sugar supplemented diet on endothelial function and blood markers of cardiovascular risk in young men. Twenty-one, healthy college-aged males were randomly assigned to either the doughnut + exercise or doughnut only groups. Both groups were fed 2 doughnuts per day, 6 days per week, for three weeks, while maintain their current diet. The exercise group completed 4 exercise training sessions per week consisting of 2 high intensity interval training bouts (up to 95% VO2peak) on a cycle ergometer and two moderate intensity, steady-state bouts (at 75% VO2peak) on a treadmill. Changes in body weight and composition, markers of endothelial function, oxidative stress, serum lipids, and blood glucose were measured in each group. As expected, cardiovascular fitness increased significantly in the doughnut-supplemented + exercise group as compared to the doughnut-supplemented (p=0.005). Significant increases in body weight (p=0.036), fat mass (p=0.013), and body fat percentage (p=0.014) were seen in the doughnut only group as compared to the doughnut + exercise group. The doughnut + exercise group showed significant improvements in fasting serum triglycerides (p=0.036), plasma insulin (p=0.039) and insulin sensitivity (HOMA; p=0.05) as compared to the doughnut only group. The doughnut + exercise group saw a significant improvement in nitric oxide availability whereas the doughnut only group experienced a significant decline (p=0.014). There were no significant changes in other markers. Despite the addition of a fat/sugar supplement of ~11,600 kcal over three weeks, 4 exercise sessions per week were sufficient to prevent a gain in body weight and fat mass, and also improve some measures of cardiometabolic risk. These results suggest that exercise may be necessary to prevent some adverse health outcomes associated with transient periods of excessive energy consumption.
ContributorsBlack, Laurie (Author) / Gaesser, Glenn (Thesis advisor) / Cataldo, Donna (Committee member) / Sweazea, Karen (Committee member) / Vega-Lopez, Sonia (Committee member) / Swan, Pamela (Committee member) / Arizona State University (Publisher)
Created2013