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- All Subjects: Nutrition
- Genre: Masters Thesis
- Creators: Arizona State University
- Status: Published
Description
Historically, researchers in the gut microbiome have deemed the composition of the microbiome as being adult by the age of two. However, recent studies have contradicted this, demonstrating statistically significant differences in the microbiome even through childhood and adolescence. This difference is important in the field of microbiome research, particularly in studies examining this relationship with weight, because even though there have been significant associations between the gut microbiome and weight, they have been largely studied in adults. The freshman year of college is an interesting time to study this relationship in younger populations, due to the lifestyle changes that make them vulnerable to weight gain. This study included N=139 participants, a majority female (N=97, 69.8%), white (N=59, 42.4%), and non-Hispanic (N=89, 64%). Participants were only included in this analysis if they gave 2 or more fecal samples over the 4 timepoint study. Samples were sequenced using the Illumina MiSeq instrument after polymerase chain reaction (PCR) amplification was performed on the V4 region of the 16S rRNA gene sequence. Statistical analysis was performed using the longitudinal plugin of QIIME2. Results demonstrate that low abundance features seemed to drive a majority of the differences in variability between those who maintained their weight over the course of the study and those who gained weight. This was demonstrated through many significant Unweighted UniFrac results with corresponding nonsignificant Weighted UniFrac data. This study demonstrated that changes in lower abundance features may have driven the significant differences in weight status in this study. This study emphasized the importance of low abundance features and how this relates to changes in weight status during a period of major lifestyle changes. Further work is needed to confirm these findings and explore how gut microbes change in free-living individuals gaining weight over time.
ContributorsAhern, Mary (Author) / Whisner, Corrie (Thesis advisor) / Bruening, Meg (Committee member) / Sears, Dorothy (Committee member) / Arizona State University (Publisher)
Created2021
Description
Objective: To conduct a content analysis of nutrition marketing in school cafeterias in Arizona to understand how nutrition concepts are currently marketed to students. This is the first study to investigate the content of nutrition marketing in school cafeterias, and also the first to compare content across elementary, middle, and high schools. Methods: Photographs of marketing materials on display in school cafeterias were obtained from a convenient sample of 13 elementary schools, 12 middle schools, and 12 high schools. In total, n=284 examples of nutrition marketing were collected. The photographs were sorted by grade level and then coded quantitatively and qualitatively based on their purpose, visual aspects, marketing strategies used, and language and literacy aspects. Given the multiple comparisons, statistical significance was assessed with a Bonferroni adjustment of p<0.0006.
Results: The average number of nutrition marketing materials within the school cafeterias was 7.7 ± 7.2. The purpose of the marketing materials ranged from promoting selection and consumption of fruits and vegetables, promoting nutrition and physical activity together, food safety, and educating about healthy eating. The sample of nutrition marketing materials emphasized selecting F/Vs over consumption of F/Vs. However, the opposite was found in marketing that exclusively promoted fruits and vegetables. The most common type of marketing in school cafeterias were flyers and most of the materials were small in size. The sample demonstrated a lack of implementation of marketing appeals in half of the sample, but the half that did utilized techniques that are known to be appealing to child and adolescent demographics, such as use of cartoons, humor, and social media/websites. 98.9% of the nutrition marketing with text were written in English and only 1.1% of the materials (n=3) were written in Spanish.
Conclusion: The nutrition marketing sample demonstrated some use of social marketing principles but does not compete with the scale and scope of the child-directed food and beverage marketing that students encounter in their environment. More research is needed to better understand how to best target nutrition marketing to child and adolescent student populations.
ContributorsXavier, Raevyn Francine (Author) / Bruening, Meg (Thesis advisor) / Adams, Marc (Committee member) / Lorts, Cori (Committee member) / Arizona State University (Publisher)
Created2021
Description
Objective: Increasing fruit/vegetable (FV) consumption and decreasing waste during the school lunch is a public health priority. Understanding how serving style of FV impacts FV consumption and waste may be an effective means to changing nutrition behaviors in schools. This study examined whether students were more likely to select, consume, and waste FV when FVs were cut vs. whole. Methods: Baseline data from the ASU School Lunch Study was used to explore associations between cut vs. whole FV serving style and objectively measured FV selection, consumption, and waste and grade level interactions among a random selection of students (n=6804; 47.8% female; 78.8% BIPOC) attending Arizona elementary, middle, and high schools (N=37). Negative binomial regression models evaluated serving style on FV weight (grams) selected, consumed, and wasted, adjusted for sociodemographics and school.
Results: Students were more likely to select cut FVs (IRR=1.11; 95% CI: 1.04, 1.18) and waste cut FVs (IRR=1.20; 95% CI: 1.04, 1.39); however, no differences were observed in the overall consumption of cut vs. whole FVs. Grade-level interactions impacted students’ selection of FVs. Middle school students had a significantly higher effect modification for the selection of cut FVs (IRR=1.18; p=0.006) compared to high school and elementary students. Further, high school students had a significantly lower effect modification for the selection of cut FVs (IRR=0.83; p=0.010) compared to middle and elementary students. No other grade-level interactions were observed.
Discussion: Serving style of FV may impact how much FV is selected and wasted, but further research is needed to determine causality between these variables.
ContributorsJames, Amber Chandarana (Author) / Bruening, Meredith (Thesis advisor) / Adams, Marc (Thesis advisor) / Koskan, Alexis (Committee member) / Arizona State University (Publisher)
Created2021
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
Background: Studies show that rural schools may be less supportive of student fruit/vegetable (FV) consumption, but few studies have investigated the relationship between school locale and FVs. The aim of this research is to analyze the relationship between school locale (rural vs. urban) and students’ FV selection, consumption, and waste in elementary, middle, and high schools. Methods: A cross-sectional analysis of 37 Arizona schools evaluated differences in the selection, consumption, and waste of fresh FVs from students (n=2525; 45.7% female; 41% non-white; mean age=11.6±3.3; 23.5% rural) using objective plate waste measures. Zero-inflated negative binomial regressions examined differences in FV grams selected, consumed, and wasted by urban vs. rural locale, adjusted for sociodemographics and school.
Results: The percent of students who selected, consumed, and wasted zero grams of FVs were 14%, 21%, 20%, respectively. Among students with some (non-zero amounts), the average selected, consumed, and wasted FVs were 115.0±81.4g, 51.7.5±65.1g, 65.2±66.7g, respectively. Rural students (versus urban) had lower odds of selecting (OR=0.75), consuming (OR=0.78), and wasting (OR=0.71) any FVs, after adjusting for covariates. However, among students with some FVs on their plates, rural students selected (IRR=1.40), consumed (IRR=1.18) and wasted (IRR=1.62) more grams of FVs.
Conclusions: Rural students had reduced odds of selecting and consuming any FVs, but with lower odds of waste, perhaps due to reduced selection. Once some FVs were on the tray, likelihood of consumption and waste by rural students were greater. Results support interventions targeting rural students’ FV intake to reduce waste.
ContributorsJepson, Molly Eilish (Author) / Bruening, Meg (Thesis advisor) / Adams, Marc (Committee member) / Grgich, Traci (Committee member) / Arizona State University (Publisher)
Created2021
Associations Between Rapid Infant Weight Gain, Infant Feeding Practice and the Infant Gut Microbiome
Description
Background: Rapid infant weight gain (RWG) by six months of age has been identified as one of the earliest indicators of childhood obesity. Previous research suggests that exclusive breastfeeding over formula feeding may serve a protective effect from RWG. In addition, the makeup of the infant gut microbiome may influence RWG as differences in feeding practices have been shown to alter the bacterial makeup of the gut, potentially impacting energy metabolism. However, little research has been conducted investigating the potential relationships between RWG, infant feeding practices, and the infant gut microbiome.Methods: This study was a pilot study, which included 31 mother-infant dyads who were primarily recruited from Women, Infant, and Children’s Supplemental Nutrition Program (WIC) clinics and by word of mouth in the Southwestern United States. Participants were followed over six months, with study staff conducting home study visits four times (pregnancy, two days postpartum, three weeks and six months). Mothers who participated in this study were majority White (n=40.6%), non-Hispanic or Latino (67.7%), and obtained a graduate degree (n=22.6%). Participants were included in this analysis (n=22) if they provided at least two infant fecal samples, and the study staff were able to collect infant anthropometric data at the three-week and six-month study visits. Microbial DNA from fecal samples was sequenced using the Illumina MiSeq instrument after polymerase chain reaction (PCR) amplification was performed on the V4 region of the 16S rRNA gene sequence. Statistical analysis was performed using the QIIME2 longitudinal plug-in.
Results: Results of this study suggested a significant difference in weighted UniFrac between infants who were exclusively breastfed and formula-fed from birth to three weeks of age. Additionally, an exploratory statistical method identified family Prevotellaceae as a potentially volatile microbe; however, this model failed to reach significance for either RWG or mode of feeding. Overall, no additional alpha or beta diversity metrics or differential abundance of microbes by either RWG or feeding practice group was found in this study.
Conclusion: Future research is warranted to further explore potential connections between RWG, infant feeding practices, and the infant gut microbiome in a longitudinal study with a larger sample size.
ContributorsToffoli, Samantha (Author) / Whisner, Corrie (Thesis advisor) / Bruening, Meg (Committee member) / Sears, Dorothy (Committee member) / Arizona State University (Publisher)
Created2021
Description
Background: Children in the United States have low diet quality scores and consume less than the recommended amounts of fruits, vegetables, whole grains, and dairy. The National School Lunch Program serves nearly 30 million children daily, and has the potential to improve the diet quality of children. However, there are high levels of food waste, particularly of fruits and vegetables. Purpose: The purpose of this study is to determine which menu items students are throwing away untouched most frequently. A secondary purpose of this study is to determine which menu items students are fully consuming most frequently.
Methods: Student participants (n=2,881) in Arizona elementary, middle, and high schools who participated in school lunch were randomly selected to participate in the study. Student lunch trays were photographed before and after the student ate. Visual estimation was used to determine if menu items were untouched or fully consumed. Menu item names were standardized and categorized into menu categories. The frequency menu items were untouched or fully consumed were summarized in percentages by menu category, and stratified by school level.
Results: Findings show that menu items within each menu category are untouched and fully consumed with different frequencies. Cold vegetable items were untouched with the greatest frequency, with 39% of all servings untouched. Some menu items were both untouched and fully consumed with high frequency.
Conclusion: Food service managers can use these results to plan menus with food items that are more popular among their students to help increase consumption and decrease waste. Future research should explore the relationship between packaging and preparation with student consumption and waste. Researchers should also examine aspects of the high school food environment that may lead to increased student consumption.
ContributorsLiddicoat, Carina Marie (Author) / Bruening, Meg (Thesis advisor) / Adams, Marc A (Committee member) / Grgich, Traci (Committee member) / Arizona State University (Publisher)
Created2022
Description
Background: Research has found that nearly a quarter of the American population follows a gluten-free diet in some capacity, while only about 1% of the population is diagnosed with celiac disease. Although the amount of research-based evidence supporting any health benefits of a gluten-free diet in an individual without a gluten- related disorder is limited, the number of people claiming to follow a gluten-free diet continues to rise. Also, despite an increasing belief that gluten is harmful for health, the potentially undesirable effects of gluten substitutions used in gluten-free foods are largely unknown. Due to the protein network encapsulating starch granules, gluten is thought to lengthen the amount of time needed during starch digestion, thereby reducing postprandial glycemia. Therefore, it is predicted that breads containing gluten will produce a lower glycemic response compared to gluten-free breads. Aim: The aim of this study was to investigate the glycemic response of gluten-free bread made with different types of flour compared to bread made with gluten-containing wheat flour. Methods: This study involved a 3-week, randomized, single blind crossover study in which 17 healthy individuals were asked to consume a different type of bread each week, 2 of which were gluten-free. Blood glucose was taken by finger prick at fasting as a baseline measurement, then for 2 hours after bread consumption in 30-minute increments. Results: Across the three groups, there was no significant difference in iAUC values after 120 minutes (p=0.192 ). The greatest mean was seen in the gluten-containing bread (145.3 ± 82.6), then the gluten-free bread made with rice flour (125.5 ± 62.8), and lastly the gluten-free bread made with potato and fava bean flour (112.4 ± 64.5). Conclusion: The inconsistent results of this study compared to previous, similar studies suggests that the postprandial glycemic response of gluten-free products can not be generalized as a whole, but instead is dependent on the type of product and the ingredients used to replace the gluten. Although the results did not show a significant difference, it does argue against the belief that gluten-free products are invariably better for health in the general, non-gluten sensitive population.
ContributorsWaznik, Lauren LaRue (Author) / Johnston, Carol (Thesis advisor) / Mayol-Kreiser, Sandra (Committee member) / Dixon, Kathleen (Committee member) / Arizona State University (Publisher)
Created2019
Description
Food insecurity and childhood obesity are both major public health concerns in the United States of America. Research has not found a definite relationship between childhood obesity and food insecurity to date, with conflicting results being found due to differences in sample sizes and protocol for measuring key variables. Preschoolers (children aged 2-5 years) are a population of particular interest as there tends to be improved health behaviors and greater adaptability to change at this period of growth and development. This study aims to evaluate if there is a relationship between food insecurity and childhood obesity with diet quality as a mediator among preschoolers in the Phoenix area. A secondary data analysis from participants (n=154) from the SAGE (Sustainability via Active Garden Education) research project was used to evaluate food insecurity status, diet quality components (kcal, saturated fat, added sugars, and servings of juice, fruits, and vegetables), and anthropometrics (waist circumference and BMI percentile). No significant associations between food insecurity status, diet quality components, and anthropometric data were found. There was an increased rate of food insecurity and childhood overweight/obesity in this sample compared to state and national averages. Further research of high quality is necessary to determine whether a relationship exists between childhood obesity and food insecurity exists and in what context. Additionally, practice and policy will need to be implemented to decrease rates of food insecurity and childhood obesity among Phoenix preschoolers.
ContributorsGutierrez, Marisa (Author) / Bruening, Meg (Thesis advisor) / Whisner, Corrie (Committee member) / Lee, Rebecca E (Committee member) / Arizona State University (Publisher)
Created2020
Description
Background: Individuals in the general populations with a known gluten disorder is believed to be 6% and it is unclear why the gluten free diet (GFD) has risen sharply (28%) in recent years. However, science has revealed that gluten can cause colonic changes in those undiagnosed with a known gluten disorder. The ramifications of these changes are unknown. Three common ingredients found in gluten free products, such as pasta, are corn quinoa and rice. Evidence from the scientific literature has shown that corn and quinoa can produce more colonic hydrogen than refined wheat and rice, indicating that corn and quinoa have a reduced glycemic effect. Since rice and wheat have similar glycemic responses, corn and quinoa pastas would be expected to have a lower glycemic response than rice and wheat pasta
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Aim The aim of his study was to examine the glycemic response to three different types of pasta: wheat, rice and corn. Breath hydrogen, assessment of mood states, blood glucose and insulin were collected after ingestion of these pastas to determine the glycemic effects of these foods.
Methods: A double blinded crossover study design was utilized on a group of healthy individuals, and the test meals of wheat, rice and combinations of rice/corn, and corn/quinoa pastas were consumed one week apart in random order. Collections of fasting venous blood samples for insulin analysis, capillary blood from a finger stick for glucose analysis, breath hydrogen samples and satiety scales were used for glycemic response and mood states were collected prior to the meal (baseline) and then again after ingestion of the test meals. Attempts were made to explore the glycemic response of these test meals in relation to mood states.
Results: The glucose response showed no significant difference at baseline (p = .683) among all groups and no significant differences were seen post treatment at 30 minutes (p = .875). However, after 60 minutes all of the glucose concentrations began to decline except for the rice pasta which peaked at 90 minutes and the wheat pasta gave the most sustained decrease. The AUC glucose values showed no significant difference at both 120 (p=0.196) and 240 (p=0.734) minutes but with wheat pasta producing the lowest mean value. The POMS scores showed no significant differences between groups over time (p=.239) but the wheat group produced the highest score (worsening moods states).
Conclusion: These results indicate that the formulation and processing of gluten free pastas may affect the rate and absorption and the subsequent glycemic response after the consumption of these foods. Whether or not wheat contains an ingredient that slows absorption and/or negatively affects mood remains undetermined warrants future research in this area.
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Aim The aim of his study was to examine the glycemic response to three different types of pasta: wheat, rice and corn. Breath hydrogen, assessment of mood states, blood glucose and insulin were collected after ingestion of these pastas to determine the glycemic effects of these foods.
Methods: A double blinded crossover study design was utilized on a group of healthy individuals, and the test meals of wheat, rice and combinations of rice/corn, and corn/quinoa pastas were consumed one week apart in random order. Collections of fasting venous blood samples for insulin analysis, capillary blood from a finger stick for glucose analysis, breath hydrogen samples and satiety scales were used for glycemic response and mood states were collected prior to the meal (baseline) and then again after ingestion of the test meals. Attempts were made to explore the glycemic response of these test meals in relation to mood states.
Results: The glucose response showed no significant difference at baseline (p = .683) among all groups and no significant differences were seen post treatment at 30 minutes (p = .875). However, after 60 minutes all of the glucose concentrations began to decline except for the rice pasta which peaked at 90 minutes and the wheat pasta gave the most sustained decrease. The AUC glucose values showed no significant difference at both 120 (p=0.196) and 240 (p=0.734) minutes but with wheat pasta producing the lowest mean value. The POMS scores showed no significant differences between groups over time (p=.239) but the wheat group produced the highest score (worsening moods states).
Conclusion: These results indicate that the formulation and processing of gluten free pastas may affect the rate and absorption and the subsequent glycemic response after the consumption of these foods. Whether or not wheat contains an ingredient that slows absorption and/or negatively affects mood remains undetermined warrants future research in this area.
ContributorsSnyder, Darren (Author) / Johnston, Carol (Thesis advisor) / Ohri-Vachaspati, Punam (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2015