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- All Subjects: Nutrition
- Creators: Johnston, Carol
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
Vitamin D deficiency has been previously associated with a higher Alzheimer’s disease (AD) risk, a condition marked by dependent living and severe cognitive impairment. AD is histologically defined by the presence of brain amyloid beta (Aβ) plaques and neurofibrillary tangles. Ways to enhance Aβ clearance have been examined in order to sustain cognition and delay AD onset. In vitro and in vivo studies suggest that vitamin D might enhance brain Aβ transportation to the periphery by up-regulating P-glycoprotein production. The purpose of this study was to examine the effect of vitamin D supplementation on plasma Aβ in an older population.
This study was a parallel-arm, double-blinded, randomized control trial. Participants consumed either a vitamin D supplement or placebo once a week for eight weeks (n=23). Only vitamin D insufficient (serum total 25-OH, D < 30 ng/mL) people were included in the study, and all participants were considered to be cognitively normal (MMSE scores > 27). Serum total 25-OH, D and plasma Aβ1-40 measurements were recorded before and after the eight-week trial. The plasma Aβ1-40 change was compared between the vitamin D group and control group.
The vitamin D group experienced a 45% greater change in plasma Aβ1-40 than the control group. The effect size was 0.228 when controlling for baseline plasma Aβ1-40 (p=0.045), 0.197 when controlling for baseline plasma Aβ1-40 and baseline physical activity (p=0.085), and 0.179 when controlling for baseline plasma Aβ1-40, baseline physical activity, and age (p=0.116). In conclusion, vitamin D supplementation might increase brain Aβ clearance in humans, but physical activity and age also appear to modulate Aβ metabolism.
This study was a parallel-arm, double-blinded, randomized control trial. Participants consumed either a vitamin D supplement or placebo once a week for eight weeks (n=23). Only vitamin D insufficient (serum total 25-OH, D < 30 ng/mL) people were included in the study, and all participants were considered to be cognitively normal (MMSE scores > 27). Serum total 25-OH, D and plasma Aβ1-40 measurements were recorded before and after the eight-week trial. The plasma Aβ1-40 change was compared between the vitamin D group and control group.
The vitamin D group experienced a 45% greater change in plasma Aβ1-40 than the control group. The effect size was 0.228 when controlling for baseline plasma Aβ1-40 (p=0.045), 0.197 when controlling for baseline plasma Aβ1-40 and baseline physical activity (p=0.085), and 0.179 when controlling for baseline plasma Aβ1-40, baseline physical activity, and age (p=0.116). In conclusion, vitamin D supplementation might increase brain Aβ clearance in humans, but physical activity and age also appear to modulate Aβ metabolism.
ContributorsMiller, Brendan Joseph (Author) / Johnston, Carol (Thesis advisor) / Whisner, Corrie (Committee member) / Tasevska, Natasha (Committee member) / Arizona State University (Publisher)
Created2015
Description
Plant-based eaters are known to reap nutritional benefits due to their dietchoice, but it is important to evaluate dietary differences that may put them at a disadvantage compared to omnivores. Stark differences exist in daily intakes of protein between vegans and omnivores, which may lead to several risks including decreased strength and bone density. The purpose of this study was to analyze the differences in protein intake, lean mass, strength, and bone density in vegans versus omnivores in order to support the argument for an increased recommended daily allowance (RDA) for protein for plant-based eaters. Participants in this study were assigned to groups based on omnivorous (n = 25) or vegan (n = 19) dietary pattern. Nineteen matched pairs were created based on age and BMI. Data was collected at a single lab visit and included health history and physical activity readiness questionnaires, 24-hr food recall, and anthropometric measures. Bone mineral density (BMD) was measured using DEXA and strength was assessed using hand and Biodex dynamometers. Statistical analyses were conducted using independent samples t-tests and Pearson’s correlation tests to evaluate differences in body composition, bone density, strength, and dietary intake between the two groups with significance set at p.05. Differences were seen in daily calorie (p=.007), protein (p<.001), fat (p<.001), and fiber (p=.009) intake. Lean mass (p=.282) and bone density (p=.651) were not different between groups, but lower body strength was different (p=.008). There was a correlation between lower body strength and protein intake (p<.001), and lean mass was correlated with lower body strength (p<.001), grip strength (p<.001), and bone density (p<.001), but not
i
LBM (p=0.158). Correlations were also observed between BMD and lower body strength (p=.004). These data suggest that there is a significant difference between protein intake in vegans versus omnivores, which appears to have a positive association with strength. BMD also has a positive association with strength as well as lean mass. Cumulatively, the results suggest that it may be beneficial for vegans to increase daily protein intake.
ContributorsNadalet, Camila R (Author) / Johnston, Carol (Thesis advisor) / Shepard, Christina (Committee member) / Hooshmand, Shirin (Committee member) / Arizona State University (Publisher)
Created2023
Description
Gastrointestinal (GI) complaints are prevalent among athletes. Fermented foods with pre-or probiotic features may relieve GI symptoms by improving gut health. This study aimed is to examine the impact of a nutritional supplement containing fermented whey protein with Galacto-oligosaccharide (GOS) fiber on GI distress among well-trained athletes over time by analyzing self-reported GI complaints without a control group. This quasi-experimental clinical trial consisted of a 3-week baseline period, reflected by two baseline measurements on Day 1 and Day 22, which was followed by a 3-week intervention period, reflected by a post-intervention measurement on Day 43, in which athletes added 15g of a fermented whey protein product to their diet. The primary outcome was based on the self-reported gastrointestinal symptom rating scale (GSRS), and the secondary outcome was based on a daily questionnaire, in which daily GI complaints and exercise occurrences were reported. Tertiary outcomes included a 24-hour diet recall (ASA24) and self-reported diet quality (REAP). Outcomes obtained during baseline (Day 1 and Day 22 average) were compared to those post-intervention (Day 43). Statistical significance was set at P<0.05. A total of n=50 athletes (24.7±4.5 years) with GI issues were included in the study. Five individual items of the GSRS including abdominal pain, acid reflux, bloating, burping, and loose stools reflected significantly lower scores on Day 43 in comparison to baseline (P≤0.028). A total of 78% reported GI complaints at baseline, and 61% of the participants reported lower GI complaints on Day 43 after supplementation in comparison to baseline (P=0.004). Further research is needed to explore the potential benefits of a hydrolyzed and fermented whey protein with prebiotics in a more controlled setting among athletic populations.
ContributorsClear, Anna Marie Grace (Author) / Wardenaar, Floris (Thesis advisor) / Johnston, Carol (Committee member) / Wharton, Christopher (Committee member) / Arizona State University (Publisher)
Created2023
Description
Sleep is an essential biological requirement to sustain human life and a critical component for athletes. There has been a rising trend for poor sleep in the general population and the problem persists as well within the athletic population. Research has demonstrated numerous benefits of optimized sleep on athletic performance and athlete wellness. Further investigation of potential dietary strategies to improve self-perceived sleep quality is warranted. This study examined the differences in perceived sleep quality and wellness between a 3-week baseline period and after a 3-week supplementation period, in which participants consumed a dietary supplement containing fermented whey protein + galacto-oligosaccharides (GOS) + casein protein daily. Validated questionnaires, namely, Athens Insomnia Scale (AIS), Physical Health Questionnaire (PHX), Kessler-6 Mental Stress Scale (K6) were used to measure perceived sleep quality and wellness on Day 1, Day 22 and Day 43. Additionally, multiple 24-h dietary recalls (ASA24), and food quality using the validated Rapid Eating Assessments for Participants (REAP) questionnaire, were used to assess dietary patterns throughout the study, while exercise occurrence was tracked through a self-developed daily questionnaire. A total of 54 healthy active adults (age=18-35yrs) experiencing gastro-intestinal (GI) complaints were included in the trial, and 50 participants were included in the final analysis. Significantly lower AIS-8 total scores were found on Day 43 compared to Day 22 while controlled for Day 1 (Day 43: 4.36 ± 3.68 versus Day 22: 5.02 ± 4.11, F=4.379 (1, 50), p=0.042), while no differences were found for wellbeing (p≥ 0.180). Dietary intake, food quality and exercise frequency did not change over time (p≥0.080). These results suggested that a daily protein + GOS supplement was associated with a decrease in AIS-8 total scores suggesting improved perceived sleep quality among athletes after 3 weeks. A controlled research study should confirm these results in the future. More research is required to assess the effects of protein + prebiotic supplementation on sleep parameters among athletes.
ContributorsChan, Yat (Author) / Wardenaar, Floris (Thesis advisor) / Johnston, Carol (Committee member) / Wharton, Christopher (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
Healthy lifestyle behaviors including quality nutrition have been shown to successfully prevent chronic disease or minimize symptoms. However, many physicians lack the knowledge and skills to provide adequate nutrition counseling and education for their patients. A major component of this problem is that medical schools are not required to teach nutrition education. The purpose of this feasibility study was to compare the changes in the perceived importance of nutrition in the medical field in medical students before and after participating in a week-long interactive nutrition course in order to determine if a week-long course can positively influence students’ perceptions of nutrition. Ultimately by changing these perceptions, medical students may be able to better help patients prevent chronic disease. The participants were first year medical students at the Mayo Clinic School of Medicine (Scottsdale, AZ) who chose to participate in this medical school “Selective”. The study included a five-day curriculum of case-studies, lectures from specialized health professionals, and a cooking class led by a chef who trained in France. An anonymous pre- and post-study questionnaire with five-point Likert scale questions was used to measure changes in attitudes. The data suggest that students’ perceptions regarding the importance and relevance of nutrition in the medical shifted slightly more positive after attending this Selective, although these shifts in attitude were not statistically significant. Limitations of this study include a small sample size and selection bias, which may have decreased the potential of having significant results. Both of these factors also make the results of this study less generalizable to all medical students. This study supports the need for a larger experimental study of a similar design to verify that an interactive, evidence-based nutrition class and culinary experience increases medical students’ positive perceptions of nutrition in the medical field.
ContributorsBaum, Makenna (Author) / Johnston, Carol (Thesis advisor) / Levinson, Simin (Committee member) / Sears, Dorothy (Committee member) / Arizona State University (Publisher)
Created2020
Description
This study was designed to examine the associations between food skills, resilience, and coping during the Covid-19 pandemic. Between April and June of 2020, a sample of 154 students, faculty, and staff from Arizona State University were surveyed. Each respondent was administered a survey containing demographic questions, a food skill questionnaire, and the 14-item Resilience Scale (RS). Results indicate that food skill was correlated with resilience (p<0.001) at an r=0.364 and r2=0.1243 and that resilience was correlated with coping during the Covid-19 pandemic (p<0.001) at an r=0.455. Correlations were also run between resilience score and the separate domains of food skill score: all domains remained significantly associated with resilience score (p<0.001) with a r=0.340 and r2=0.1173 for ‘Food Selection and Planning,’ r=0.312 and r2=0.0958 for ‘Food Preparation,’ and r=0.294 and r2=0.0767 for ‘Food Safety.’ Data seems to be consistent with contemporary research suggesting positive associations between diet quality and physiological resilience and positive associations between resilience and coping during the Covid-19 pandemic.
ContributorsPhares, Savanna Julene (Author) / Johnston, Carol (Thesis advisor) / McCoy, Maureen (Committee member) / Irving, Andrea (Committee member) / Arizona State University (Publisher)
Created2020
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