Matching Items (19)
Filtering by
- All Subjects: Nutrition
- Creators: Dixon, Kathleen
Description
An understanding of diet habits is crucial in implementing proper management strategies for wildlife. Diet analysis, however, remains a challenge for ruminant species. Microhistological analysis, the method most often employed in herbivore diet studies, is tedious and time consuming. In addition, it requires considerable training and an extensive reference plant collection. The development of DNA barcoding (species identification using a standardized DNA sequence) and the availability of recent DNA sequencing techniques offer new possibilities in diet analysis for ungulates. Using fecal material collected from controlled feeding trials on pygmy goats, (Capra hicus), novel DNA barcoding technology using the P6-loop of the chloroplast trnL (UAA) intron was compared with the traditional microhistological technique. At its current stage of technological development, this study demonstrated that DNA barcoding did not enhance the ability to detect plant species in herbivore diets. A higher mean species composition was reported with microhistological analysis (79%) as compared to DNA barcoding (50%). Microhistological analysis consistently reported a higher species presence by forage class. For affect positive species identification, microhistology estimated an average of 89% correct detection in control diets, while DNA barcoding estimated 50% correct detection of species. It was hypothesized that a number of factors, including variation in chloroplast content in feed species and the effect of rumen bacteria on degradation of DNA, influenced the ability to detect plant species in herbivore diets and concluded that while DNA barcoding opens up new possibilities in the study of plant-herbivore interactions, further studies are needed to standardize techniques and for DNA bar-coding in this context.
ContributorsMurphree, Julie Joan (Author) / Miller, William H. (Thesis advisor) / Steele, Kelly (Committee member) / Salywon, Andrew (Committee member) / Arizona State University (Publisher)
Created2012
Description
Objective: Vinegar consumption studies have demonstrated possible therapeutic effects in reducing HbA1c and postprandial glycemia. The purpose of the study was to closely examine the effects of a commercial vinegar drink on daily fluctuations in fasting glucose concentrations and postprandial glycemia, and on HbA1c, in individuals at risk for Type 2 Diabetes Mellitus (T2D). Design: Thirteen women and one man (21-62 y; mean, 46.0±3.9 y) participated in this 12-week parallel-arm trial. Participants were recruited from a campus community and were healthy and not diabetic by self-report. Participants were not prescribed oral hypoglycemic medications or insulin; other medications were allowed if use was stable for > 3 months. Subjects were randomized to one of two groups: VIN (8 ounces vinegar drink providing 1.5 g acetic acid) or CON (1 vinegar pill providing 0.04 g acetic acid). Treatments were taken twice daily immediately prior to the lunch and dinner meals. Venous blood samples were drawn at trial weeks 0 and 12 to measure insulin, fasting glucose, and HbA1c. Subjects recorded fasting glucose and 2-h postprandial glycemia concentrations daily using a glucometer. Results: The VIN group showed significant reductions in fasting capillary blood glucose concentrations (p=0.05) that were immediate and sustained throughout the duration of the study. The VIN group had reductions in 2-h postprandial glucose (mean change of −7.6±6.8 mg/dL over the 12-week trial), but this value was not significantly different than that for the CON group (mean change of 3.3±5.3 mg/dL over the 12-week trial, p=0.232). HbA1c did not significantly change (p=0.702), but the reduction in HbA1c in the VIN group, −0.14±0.1%, may have physiological relevance. Conclusions: Significant reductions in HbA1c were not observed after daily consumption of a vinegar drink containing 1.5 g acetic acid in non-diabetic individuals. However, the vinegar drink did significantly reduce fasting capillary blood glucose concentrations in these individuals as compared to a vinegar pill containing 0.04 g acetic acid. These results support a therapeutic effect for vinegar in T2D prevention and progression, specifically in high-risk populations.
ContributorsQuagliano, Samantha (Author) / Johnston, Carol (Thesis advisor) / Appel, Christy (Committee member) / Dixon, Kathleen (Committee member) / Arizona State University (Publisher)
Created2013
Description
There are multivariate factors that not only play a role in an individual's ability to lose weight, but may create barriers to his or her success. One such factor is internalized weight bias (IWB), which is inversely associated with weight loss outcomes and body satisfaction, and directly associated with psychosocial maladjustments such as depression and binge eating. This study examined the relationship between internalized weight bias and weight loss outcomes using a coding scheme developed for an online weight loss forum to see whether results would be consistent with self-administered surveys that measure IWB. The coding scheme was developed using an exploratory factor analysis of a survey composed of existing measures of IWB. Participants' posts within an online weight loss forum were coded and participants given a weekly IWB score that was compared to weekly weight loss using mixed model analysis. No significance was found between IWB and weight loss outcomes in this study, however, the coding scheme developed is a novel approach to measuring IWB, and the categories identified from latent constructs of IWB may be used in the future to determine the dimensions that exist within it. Ultimately, a better understanding of IWB could lead to the development of targeted weight loss interventions that address the beliefs and attitudes held by individuals who experience it.
ContributorsEscajeda, Janessa (Author) / Hekler, Eric (Thesis advisor) / Barroso, Cristina (Thesis advisor) / Dixon, Kathleen (Committee member) / Arizona State University (Publisher)
Created2015
Description
This study examined the effect of consuming pinto, black, and dark red kidney beans with white rice in comparison to a white rice only control meal on the glycemic response of adults with type 2 diabetes (T2D). These bean and rice combinations are part of many traditional diets. Seventeen subjects with T2D treated by diet and/or metformin were randomly assigned to 4 treatments: white rice (control), pinto beans/rice, black beans/rice, and dark red kidney beans/rice. All treatments were portioned by weight and matched for available carbohydrate content of ∼ 50 grams. Capillary whole blood samples were collected at baseline and at 30, 60, 90, 120, 150 and 180 minutes posttreatment and assessed for glucose concentration using the YSI Stat Plus Analyzer. Net change glucose responses were significantly lower for the pinto, black, and dark red kidney bean and rice meals than control at 90, 120 and 150 minutes posttreatment (P < 0.05). Incremental area under the curve (iAUC) values were also significantly reduced for the bean/rice meals containing pinto (P < 0.01) and black beans (P < 0.05) in contrast to the rice control. Results suggest that the combination of whole beans and rice may be beneficial to those with T2D to assist with blood glucose management.
ContributorsThompson, Sharon (Author) / Winham, Donna M (Thesis advisor) / Beezhold, Bonnie (Committee member) / Dixon, Kathleen (Committee member) / Arizona State University (Publisher)
Created2011
Description
Water makes up about 45-70% of a human body's total weight. It is estimated that 80% of the human brain's tissue is composed of water. Cognitive productivity is altered when the body is in a mere 2% dehydrated state. Several cognitive functions impacted by dehydration include: visual motor tracing, short-term recall, attentiveness, and mathematic efficiency. It is estimated that 80% of the U.S. adult population endures the majority of their day in a mildly dehydrated state.
Participants were employees working full-time jobs with Arizona State University or Tri Star Motor Company. Employees had to be 18 or older were invited to join the study. Employees participating in the study lived within the the greater Phoenix area. Participants of all races, genders, activity statuses, and BMIs were encouraged to join.
A one-arm, pre-test, post-test study design was utilized. We examined whether the hydration status of participants in the intervention improved or worsened during the course of the intervention, and then attributed any such improvement or deterioration to the intervention. Urine collections from an afternoon sample were gathered before and after the one-week intervention. For the intervention, the participating offices received a water dispensing system in close proximity to employee desk spaces. A reusable water bottle was also given to each participant. Urine specific gravity (USG) was assessed in all urine samples to indicate hydration status, and all participants completed water intake surveys before and after the intervention.
From this study, the overall change in water intake over the course of the one-week intervention was 143 ounces/day. This is an average of adding two and a half 8 oz glasses of water each day of the week per participant. USG also decreased significantly at the end of the intervention in comparison to the baseline value. In the greater body of research, this study strengthens the viability of inputting a hydration station and offering reusable water bottles to employees. This cost-effective method is an easy way to incorporate employee wellness in the workplace. The benefit of employees to drink more water is numerous, including increased focus, mental reactivity, and overall mood and wellness.
Participants were employees working full-time jobs with Arizona State University or Tri Star Motor Company. Employees had to be 18 or older were invited to join the study. Employees participating in the study lived within the the greater Phoenix area. Participants of all races, genders, activity statuses, and BMIs were encouraged to join.
A one-arm, pre-test, post-test study design was utilized. We examined whether the hydration status of participants in the intervention improved or worsened during the course of the intervention, and then attributed any such improvement or deterioration to the intervention. Urine collections from an afternoon sample were gathered before and after the one-week intervention. For the intervention, the participating offices received a water dispensing system in close proximity to employee desk spaces. A reusable water bottle was also given to each participant. Urine specific gravity (USG) was assessed in all urine samples to indicate hydration status, and all participants completed water intake surveys before and after the intervention.
From this study, the overall change in water intake over the course of the one-week intervention was 143 ounces/day. This is an average of adding two and a half 8 oz glasses of water each day of the week per participant. USG also decreased significantly at the end of the intervention in comparison to the baseline value. In the greater body of research, this study strengthens the viability of inputting a hydration station and offering reusable water bottles to employees. This cost-effective method is an easy way to incorporate employee wellness in the workplace. The benefit of employees to drink more water is numerous, including increased focus, mental reactivity, and overall mood and wellness.
ContributorsWildermuth, Kelsi (Author) / Johnston, Carol (Thesis advisor) / Dixon, Kathleen (Committee member) / Levinson, Simin (Committee member) / Arizona State University (Publisher)
Created2018
Description
Vegetarian diets can provide an abundance of nutrients when planned with care. However, research suggests that vegetarian diets may have lower protein quality than omnivore diets. Current protein recommendations assume that vegetarians obtain a majority of their protein from animal products, like dairy and eggs. Studies have shown that this assumption may not be valid. The recommended dietary allowance (RDA) may not be adequate in vegetarian populations with high protein requirements. The purpose of this study is to analyze dietary protein quality using the DIAAS (Digestible Indispensable Amino Acid Score) method in both vegetarian and omnivore endurance athletes. 38 omnivores and 22 vegetarians submitted 7-day food records which were assessed using nutrition analysis software (Food Processor, ESHA Research, Salem, OR, USA). Dietary intake data was used to calculate DIAAS and determine the amount of available dietary protein in subject diets. Dietary data was compared with the subjects’ lean body mass (obtained using DEXA scan technology), and strength (quantified using peak torque of leg extension and flexion using an isokinetic dynamometer). Statistical analyses revealed significantly higher available protein intake in the omnivore athletes (p<.001). There were significant correlations between available protein intake and strength (p=.016) and available protein intake and lean body mass (p<.001). Omnivore subjects had higher lean body mass than vegetarian subjects (p=.011). These results suggest that vegetarian athletes may benefit from higher overall protein intakes to make up for lower dietary protein quality.
ContributorsZuelke, Corinne (Author) / Johnston, Carol (Thesis advisor) / Wharton, Christopher (Christopher Mack), 1977- (Committee member) / Dixon, Kathleen (Committee member) / Arizona State University (Publisher)
Created2017
Description
ABSTRACT
Many natural interventions have been effective at lowering postprandial glucose concentrations (PPG) in research trials and, theoretically, should have favorable effects on the prevention and management of T2DM. Natural interventions include vinegar, nuts and exercise. Green tea has been demonstrated to also possessing antiglycemic effects. Thus, green tea, and its most abundant catechin EGCG, are being consumed for its potential health benefits in cancer prevention and in its inhibitory effects on α-amylase. Many studies have found EGCG to inhibit α-amylase an enzyme needed in the breakdown of carbohydrates (CHO). Other studies have looked at EGCG and its potential for lowering PPG concentrations due to its inhibitory effects on α-amylase in both mice and humans. Yet there is no research on Matcha tea specifically. Matcha tea is green tea in powder form; hence, it is consumed in its entirety unlike traditional teas which are steeped in bags. The purpose of this study was to determine whether Macha tea impacts PPG concentrations in healthy adults. Twelve subjects completed this randomized controlled, single blinded, crossover study. On three separate occasions the twelve subjects consumed a bagel and jam with either water, Lipton green tea, or Macha tea. Fasting blood glucose was taken upon their arrival. Once the tea or water and bagel with jam were consumed PPG concentrations were measured every 30 minutes until 120 minutes were reached. Results showed no statistically significant effects on PPG concentrations in either test groups (p=.960). However, this study did not measure EGCG levels in the tea provided. Therefore, further research should be done with known EGCG amounts to see its effects on PPG concentrations to fully rule out its potential.
Many natural interventions have been effective at lowering postprandial glucose concentrations (PPG) in research trials and, theoretically, should have favorable effects on the prevention and management of T2DM. Natural interventions include vinegar, nuts and exercise. Green tea has been demonstrated to also possessing antiglycemic effects. Thus, green tea, and its most abundant catechin EGCG, are being consumed for its potential health benefits in cancer prevention and in its inhibitory effects on α-amylase. Many studies have found EGCG to inhibit α-amylase an enzyme needed in the breakdown of carbohydrates (CHO). Other studies have looked at EGCG and its potential for lowering PPG concentrations due to its inhibitory effects on α-amylase in both mice and humans. Yet there is no research on Matcha tea specifically. Matcha tea is green tea in powder form; hence, it is consumed in its entirety unlike traditional teas which are steeped in bags. The purpose of this study was to determine whether Macha tea impacts PPG concentrations in healthy adults. Twelve subjects completed this randomized controlled, single blinded, crossover study. On three separate occasions the twelve subjects consumed a bagel and jam with either water, Lipton green tea, or Macha tea. Fasting blood glucose was taken upon their arrival. Once the tea or water and bagel with jam were consumed PPG concentrations were measured every 30 minutes until 120 minutes were reached. Results showed no statistically significant effects on PPG concentrations in either test groups (p=.960). However, this study did not measure EGCG levels in the tea provided. Therefore, further research should be done with known EGCG amounts to see its effects on PPG concentrations to fully rule out its potential.
ContributorsRomash, Roni (Author) / Johnston, Carol (Thesis advisor) / Dixon, Kathleen (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2018
Description
University students currently lack sufficient knowledge and resources needed to support healthy eating patterns and nutrition. Comparison of the number of registered dietitians that are available to all students, along with the number of wellness events that are held at each university within the Pacific-12 conference will help determine which schools are best able to support their students' needs. Data was collected using a Google forms survey sent via email to wellness directors of each of the universities in the Pac-12 conference. Eight out of the twelve schools in the conference responded to the survey. The average number of dietitians available to all students (regardless of athlete status) was found to be 1.43 dietitians. Of the schools that responded, the University of Colorado, Boulder, has the most resources dedicated to student nutrition wellness with three dietitians available for all undergraduate students, free dietitian services, and approximately 150 wellness events each year. The success of available nutrition wellness resources was inconclusive as schools did not provide the information regarding student utilization and attendance. Future university promoted nutrition wellness programs should increase the number of affordable dietitians and total wellness events, as well as promote student health services through social media platforms to improve student nutrition knowledge and usage of resources.
ContributorsCurtin, Anne Clare (Author) / Dixon, Kathleen (Thesis director) / McCoy, Maureen (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Is it possible to treat the mouth as a natural environment, and determine new methods to keep the microbiome in check? The need for biodiversity in health may suggest that every species carries out a specific function that is required to maintain equilibrium and homeostasis within the oral cavity. Furthermore, the relationship between the microbiome and its host is mutually beneficial because the host is providing microbes with an environment in which they can flourish and, in turn, keep their host healthy. Reviewing examples of larger scale environmental shifts could provide a window by which scientists can make hypotheses. Certain medications and healthcare treatments have been proven to cause xerostomia. This disorder is characterized by a dry mouth, and known to be associated with a change in the composition, and reduction, of saliva. Two case studies performed by Bardow et al, and Leal et al, tested and studied the relationships of certain medications and confirmed their side effects on the salivary glands [2,3]. Their results confirmed a relationship between specific medicines, and the correlating complaints of xerostomia. In addition, Vissink et al conducted case studies that helped to further identify how radiotherapy causes hyposalivation of the salivary glands [4]. Specifically patients that have been diagnosed with oral cancer, and are treated by radiotherapy, have been diagnosed with xerostomia. As stated prior, studies have shown that patients having an ecologically balanced and diverse microbiome tend to have healthier mouths. The oral cavity is like any biome, consisting of commensalism within itself and mutualism with its host. Due to the decreased salivary output, caused by xerostomia, increased parasitic bacteria build up within the oral cavity thus causing dental disease. Every human body contains a personalized microbiome that is essential to maintaining health but capable of eliciting disease. The Human Oral Microbiomics Database (HOMD) is a set of reference 16S rRNA gene sequences. These are then used to define individual human oral taxa. By conducting metagenomic experiments at the molecular and cellular level, scientists can identify and label micro species that inhabit the mouth during parasitic outbreaks or a shifting of the microbiome. Because the HOMD is incomplete, so is our ability to cure, or prevent, oral disease. The purpose of the thesis is to research what is known about xerostomia and its effects on the complex microbiome of the oral cavity. It is important that researchers determine whether this particular perspective is worth considering. In addition, the goal is to create novel experiments for treatment and prevention of dental diseases.
ContributorsHalcomb, Michael Jordan (Author) / Chen, Qiang (Thesis director) / Steele, Kelly (Committee member) / Barrett, The Honors College (Contributor) / College of Letters and Sciences (Contributor)
Created2015-05
Description
Pet obesity is higher than ever in the United States. According to the Association for Pet Obesity Prevention, 52.5% of dogs and 58.3% of cats were either overweight or obese in 20121. Obesity has been linked to health issues such as cardiovascular disease, diabetes, muscular disorders and some cancers to name a few.2 A pet at the recommended healthy weight is important to avoid these diseases. It is important that owners realize this and if their pet is at an unhealthy weight, work with their veterinarian to help the pet lose weight. This study looks at how committed dog owners are to help their pet lose weight and the problems they face while doing so.
ContributorsHarvey, Alexandra Patricia (Author) / Thatcher, Craig (Thesis director) / Steele, Kelly (Committee member) / Barrett, The Honors College (Contributor) / School of Letters and Sciences (Contributor)
Created2014-05