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- All Subjects: Nutrition
- Creators: Shepard, Christina
- Member of: Theses and Dissertations
- Status: Published
Description
The gold standard for bone measurement is DXA (dual energy X-ray absorptiometry). Typically, to observe changes in bone by DXA, a minimum of a 4-month intervention is required. Serum osteocalcin (OST) (a bone formation marker) and quantitative ultrasound (QUS) of the calcaneus can be used as indicators of bone change but the sensitivity and time course of these indices to short term interventions are unknown. The purpose of this study was twofold: to compare monthly changes in OST and QUS in response to jump training and to evaluate the relationship between DXA, OST and QUS. Young women with QUS t-scores less than 1.0 were randomized into a jump training (J) (n=16) or control (C) (n=16). J consisted of a progressive routine of 1 and 2-footed jumping performed 3 days per week for 4 months. Body composition, QUS and OST were measured at baseline, and monthly for 4 months. DXA and 24-hour dietary recalls were completed at baseline and 4 months. Low attrition rate (12.5%) and high compliance (98%) with the exercise intervention was recorded. No significant correlations between QUS and OST existed. No significant differences were observed between groups at baseline in body composition or bone variables. Monthly increases in OST were observed but there were no significant differences over time between groups in any bone variables. OST and QUS may be indicative of short term bone changes but these variables were not specifically sensitive to the jumping intervention in this population of women.
ContributorsHeumann, Kristin Joelle (Author) / Swan, Pamela D (Thesis advisor) / Alvar, Brent (Committee member) / Chisum, Jack (Committee member) / Lee, Chong (Committee member) / Vaughan, Linda (Committee member) / Arizona State University (Publisher)
Created2011
Description
The antioxidant, antihistamine, and chemotactic properties of vitamin C provide the theoretical basis linking vitamin C supplementation to combating the common cold; yet, the clinical evidence is mixed. To date, vitamin C intervention trials have not systematically recorded cold symptoms daily or looked at fluctuations in plasma histamine over an extended period. Also, trials have not been conducted in individuals with marginal vitamin C status. This study examined the impact of vitamin C supplementation during cold season on specific cold symptoms in a population with low plasma vitamin C concentrations. Healthy young males who were not regular smokers or training for competitive sports between the ages of 18 and 35 with below average plasma vitamin C concentrations were stratified by age, body mass index, and vitamin C status into two groups: VTC (500 mg vitamin C capsule ingested twice daily) or CON (placebo capsule ingested twice daily). Participants were instructed to fill out the validated Wisconsin Upper Respiratory Symptom Survey-21 daily for 8 weeks. Blood was sampled at trial weeks 0, 4, and 8. Plasma vitamin C concentrations were significantly different by groups at study week 4 and 8. Plasma histamine decreased 4.2% in the VTC group and increased 17.4% in the CON group between study weeks 0 and 8, but these differences were not statistically significant (p>0.05). Total cold symptom scores averaged 43±15 for the VTC group compared to 148±36 for the CON group, a 244% increase in symptoms for CON participants versus VTC participants (p=0.014). Additionally, recorded symptom severity and functional impairment scores were lower in the VCT group than the CON group (p=0.031 and 0.058, respectively). Global perception of sickness was 65% lower in the VTC group compared to the CON group (p=0.022). These results suggest that 1000 mg of vitamin C in a divided dose daily may lower common cold symptoms, cold symptom severity, and the perception of sickness. More research is needed to corroborate these findings.
ContributorsOsterday, Gillean (Author) / Johnston, Carol (Thesis advisor) / Beezhold, Bonnie (Committee member) / Vaughan, Linda (Committee member) / Arizona State University (Publisher)
Created2012
Description
Background Hemodialysis (HD) patients elicit an oxidant-antioxidant imbalance in addition to a selenium deficiency, possibly contributing to cardiovascular disease (CVD) mortality. Objective To evaluate the effect of selenium supplementation on CVD outcomes and antioxidant status in HD patients. Design A randomized controlled intervention trial conducted from October 2012 to January 2013. Participants/setting The study included 27 maintenance HD patients (61.1+17.5y, 14M, 13F) receiving HD in the greater Phoenix, AZ area. Intervention Patients received one of three treatments daily: 2 Brazil nuts, (5g, 181µg/day of selenium as selenomethionine [predicted]), 1 tablet of selenium (200µg/day of selenium as selenomethionine), or control (3 gummy bears). Main outcome measures Antioxidant status outcome measures included total antioxidant capacity, vitamin C, and RBC and plasma glutathione peroxidase (GSH-Px). CVD outcomes measures included brain natriuretic peptide; plasma cholesterol, high density lipoprotein, low density lipoprotein, triglycerides; blood pressure, and thoracic cavity fluid accumulation. Statistical analyses performed Repeated measures ANOVA analyzed changes over time and between groups at months 0 and 2 and months 0 and 3. Results Independent analysis showed the Brazil nuts provided 11µg of selenium/day and the pill provided 266µg of selenium/day. Consequently, the Brazil nut group was combined with the placebo group. 21 patients completed 2 months of the study and 17 patients completed the study in its entirety. Data was analyzed for months 0, 1 and 2. No significant differences were noted for antioxidant status outcome measures with the exception of plasma GSH-Px. Patients receiving the selenium pill had a significant increase in plasma GSH-Px compared to the placebo group (6.0+11 and -4.0+7.6, respectively, p=0.023 for change between month 0 and month 2). No significant differences were seen in total antioxidant capacity or for CVD outcome measures over time or between groups. Conclusions These data indicate that selenium supplementation increased plasma GSH-Px concentration in HD patients; however, oxidative stress was not altered by selenium supplementation. The low vitamin C status of HD patients warrants further research, specifically in conjunction with selenium supplementation.
ContributorsSussman, Elizabeth Jessica (Author) / Johnston, Carol S (Thesis advisor) / Boren, Kenneth (Committee member) / Mayol-Kreiser, Sandra (Committee member) / Sweazea, Karen (Committee member) / Vaughan, Linda (Committee member) / Arizona State University (Publisher)
Created2013
Description
In 2002, a scientifically derived food guide pyramid for vegetarians, the Modified Food Guide for Lacto-ovo-vegetarians and Vegans was published and well received. Now that 10 years have passed, new scientific literature regarding the bioavailability of the nutrients of key concern in vegetarian diets has been published, and the graphical format of the nation's food guide has evolved from a pyramid shape into a circular plate. The objective of this research was to examine the post-2002 literature regarding the bioavailability of key nutrients in vegetarian diets; to use this information to update the recommendations made in the 2002 Modified Food Guide Pyramid for Lacto-ovo-vegetarians and Vegans; and to adapt this revised food plan to the new USDA MyPlate format. This process involved reviewing the scientific literature to determine if the DRIs for the nutrients of key concern in vegetarian diets are adequate for the vegetarian population and using this information to develop new recommendations for vegetarians if necessary, analyzing the nutrient content of representative foods in different food groups, reconfiguring the food groups so that foods with like nutrient components were grouped together, determining the number of servings of each food group required to meet vegetarians' nutrient requirements at three caloric levels, and developing sample menus. A circular plate graphic, the Vegetarian Plate, was designed to illustrate the recommendations of this updated food guide. This updated, scientifically derived food guide provides a sound base for diet planning for lacto-ovo-vegetarians and vegans. Further research is needed to assess the Vegetarian Plate's adequacy for children, pregnant and lactating women, athletes, and individuals with medical conditions or chronic diseases.
ContributorsFladell, Lauren (Author) / Johnston, Carol (Thesis advisor) / Vaughan, Linda (Committee member) / Shepard, Christina (Committee member) / Arizona State University (Publisher)
Created2013
Description
Background. Research suggests that non-O blood types are at an increased risk of thrombosis and related health complications in cardiovascular disease (CVD). This is due in part to higher concentrations of von Willebrand factor (VWF), an important factor involved in blood clotting. Objective. The purpose of this study was to examine the effects of a vegetarian-like diet on blood coagulation and other health parameters in adults with type A blood compared to type O blood over a four week intervention. Given the lack of previous research on blood type and diet, it was hypothesized that no difference in blood coagulation would be observed. Design. This study was a randomized, parallel arm, dietary intervention using healthy, omnivorous adults with blood types A and O. A total of 39 subjects completed the study. Subjects were randomized into two groups: a vegetarian-like diet group made up of 12 type As and 12 type Os and an omnivorous control diet group made up of 11 type As and 12 type Os. At weeks 0 and 4, fasting blood was drawn and analyzed for prothrombin time (PT), activated partial thromboplastin time (APTT), von Willebrand factor (VWF), total cholesterol, LDL, HDL, triglycerides, and CRP. In addition, subjects were weighed and filled out a FFQ at weeks 0 and 4. Results. After adhering to a vegetarian-like diet for four weeks, type Os had a significant increase in PT (+0.24±0.32 sec/ p=0.050), whereas type As saw no significant change. There was a trend of weight loss for type Os in the vegetarian-like diet group (-1.8±2.6 lb/ p=0.092) and significant weight loss for type As (-0.9±2.1 lb/ p=0.037). Both blood types O and A experienced significant decreases in BMI (-0.3±0.4/ p=0.092 and -0.2±0.3/ p=0.037, respectively). No change was seen in APTT, VWF, total cholesterol, LDL, HDL, triglycerides, or CRP. Conclusion. Type Os saw an increase in PT, perhaps indicating a reduction in risk of thrombosis and its related health complications. Type As were less responsive to the dietary intervention and may require more rigid dietary guidelines or a longer time on such a diet to see the benefits.
ContributorsBrown, Jennifer (Author) / Johnston, Carol (Thesis advisor) / Martin, Keith (Committee member) / Shepard, Christina (Committee member) / Arizona State University (Publisher)
Created2013
Description
Background: Obesity is considered one of the most serious public health issues worldwide. Small, feasible lifestyle changes are necessary to obtain and maintain weight loss. Clinical evidence is inconclusive about whether meal preloading is an example of a small change that could potentially increase the likelihood of weight loss and weight maintenance. Objective: The aim of this study is to determine if consuming 23 grams of peanuts, as a meal preload, before a carbohydrate-rich meal will lower post prandial glycemia and insulinemia and increase satiety in the 2 hour period after a carbohydrate-rich meal. Design: 15 healthy, non-diabetic adults without any known peanut or tree nut allergies were recruited from a campus community. A randomized, 3x3 block crossover design was used. The day prior to testing participants refrained from vigorous activity and consumed a standard dinner meal followed by a 10 hour fast. Participants reported to the test site in the fasted state to complete one of three treatment meals: control (CON), peanut (NUT), or grain bar (BAR) followed one hour later by a carbohydrate-rich meal. Satiety, glucose and insulin were measured at different time points throughout the visit. Each participant had a one-week washout period between visits. Results: Glucose curves varied between treatments (p=.023). Blood glucose was significantly higher one hour after ingestion of the grain bar compared to the peanut and control treatments (p<.001). At 30 minutes after the meal, the control glucose was significantly higher than for the peanut or grain bar (p=.048). Insulin did vary significantly between treatments (p<.001). The insulin change one hour after grain bar consumption was significantly higher than after the peanut or control at the same time point (p<.001). The change in insulin one hour after peanut consumption was significantly higher than for the control treatment (p=.002). Overall satiety, expressed as the 180 minute AUC, differed significantly between treatments (p=.001). One hour after preload consumption, peanut and bar consumption was associated with greater satiety than the water control (p<.001). At 30 minutes post-meal, the grain bar was associated with greater satiety versus the water control (p=.049). The bar was also associated with greater satiety versus peanut and control at 60 and 90 minutes post-meal (p=.003 and .034, respectively). At 120 minutes post-meal, the final satiety measurement, the bar was still associated with greater satiety than the peanut preload (p=.023). Total energy intake, including test meal, on treatment days did not differ significantly between treatment (p=.233). Conclusions: Overall satiety, blood glucose and blood insulin levels differed at different time points depending on treatment. Both meal preloads increased overall satiety. However, grain bar ingestion resulted in sustained satiety, greater than the peanut preload. Grain bar ingestion resulted in an immediate glycemic and insulinemic response. However, the response was not sustained after the test meal was ingested. The results of this study suggest that a low-energy, carbohydrate-rich meal preload may have a positive impact on weight maintenance and weight loss by initiating a sustained increase in overall satiety. More research is needed to confirm these findings.
ContributorsFleming, Katie R (Author) / Johnston, Carol (Thesis advisor) / Wharton, Christopher (Christopher Mack), 1977- (Committee member) / Shepard, Christina (Committee member) / Arizona State University (Publisher)
Created2012
Description
ABSTRACT Fruit and vegetable intake is not uniform across levels of socioeconomic status (SES) and researchers have identified low SES as a risk factor for poor intake of fruits and vegetables. In an effort to eliminate public health disparities and increase fruit and vegetable intake, the Women, Infant, and Children (WIC) program implemented additional food assistance programs, with a specific emphasis on fresh fruits and vegetables. The Farmers' Market Nutrition Program (FMNP) provides pre-existing WIC clients with coupons to purchase fresh, locally grown produce at farmers' markets. In addition, Congress also approved the WIC Cash Value Voucher (CVV) program, which provides WIC participants with vouchers to purchase fresh fruits and vegetables at farmers' markets or grocery stores. The purpose of this thesis was to investigate the relation of FMNP coupon use with accessibility and WIC CVV redemption rates at farmers' markets. Furthermore, this thesis addressed whether WIC shoppers redeemed a higher percentage of their WIC CVV value at farmers' markets or grocery stores. WIC CVV and FMNP issuance and redemption data were analyzed to establish overall redemption rates and total perecent of WIC CVV value redeemed. Accessibility was assessed using the Geographic Information System, which allowed me to calculate the distance that WIC participants would have to travel to redeem their FMNP coupons at FMNP-approved farmers' markets. The results showed that less than 1% of WIC shoppers redeem their WIC CVVs at farmers'markets in Arizona. However, the redemption of WIC CVV was significantly higher during the months when shoppers had the option of using both WIC CVV and FMNP coupons at farmers' markets. Furthermore, the percent of total CVV value redeemed at farmers' markets was 99%, significantly higher than grocery stores (93.5%). Average FMNP coupon redemption rates for 2008-2010 was 43.3%, well below the national average of 59%. However, my spatial analysis revealed that there was no significant association between the distance traveled to farmers' markets and FMNP redemption rates. This indicates that the distance traveled to farmers' markets is not a major barrier to redemption of FMNP coupons in Arizona.
ContributorsTucker, Wesley Jack (Author) / Wharton, Christopher (Christopher Mack), 1977- (Thesis advisor) / Vaughan, Linda (Committee member) / Johnston, Carol S (Committee member) / Arizona State University (Publisher)
Created2012
Description
ABSTRACT This randomized, controlled, double-blind crossover study examined the effects of a preprandial, 20g oral dose of apple cider vinegar (ACV) on colonic fermentation and glycemia in a normal population, with the ultimate intention of identifying the mechanisms by which vinegar has been shown to reduce postprandial glycemia and insulinemia. Fifteen male and female subjects were recruited, ages 20-60y, who had no prior history of gastrointestinal (GI) disease or resections impacting normal GI function, were non-smokers, were non-vegetarian/vegan, were not taking any medications known to alter (glucose) metabolism, and were free of chronic disease including diabetes. Subjects were instructed to avoid exercise, alcohol and smoking the day prior to their trials and to consume a standardized, high-carbohydrate dinner meal the eve prior. There was a one-week washout period per subject between appointments. Breath hydrogen, serum insulin and capillary glucose were assessed over 3 hours after a high-starch breakfast meal to evaluate the impact of preprandial supplementation with ACV or placebo (water). Findings confirmed the antiglycemic effects of ACV as documented in previous studies, with significantly lower mean blood glucose concentrations observed during ACV treatment compared to the placebo at 30 min (p=0.003) and 60 min (p=0.005), and significantly higher mean blood glucose concentrations at 180 min (p=0.045) postprandial. No significant differences in insulin concentrations between treatments. No significant differences were found between treatments (p>0.05) for breath hydrogen; however, a trend was observed between the treatments at 180 min postprandial where breath hydrogen concentration was visually perceived as being higher with ACV treatment compared to the placebo. Therefore, this study failed to support the hypothesis that preprandial ACV ingestion produces a higher rate of colonic fermentation within a 3 hour time period following a high-carbohydrate meal. Due to variations in experiment duration noted in other literature, an additional study of similar nature with an expanded specimen collections period, well beyond 3 hours, is warranted.
ContributorsMedved, Emily M (Author) / Johnston, Carol (Thesis advisor) / Sweazea, Karen (Committee member) / Shepard, Christina (Committee member) / Arizona State University (Publisher)
Created2012
Description
Cardiovascular disease (CVD) is the primary killer of Americans. As such, alternative means of a dietary approach to preventing or mitigating the development of CVD is clearly needed in addition to the ongoing recommendation for increased consumption of fruits and vegetables. Many studies suggest that fungi have the potential to decrease morbidity and mortality associated with CVD. Specifically, white button mushrooms, viz., Agaricus bisporus, are fairly common and inexpensive and full of untapped possibilities for efficacy although much additional research is needed. With antioxidants, e.g., selenium, and beta-glucans, viz., indigestible polysaccharides, white button mushrooms contain a plethora of bioactive ingredients that confer a potentially strong tool against the debilitating social impact of CVD.
The objective of this thesis was to establish protocols and a valid experimental design for testing whether dietary mushrooms could, in fact, be protective against CVD risk. Specifically, a case-study approach was used to validate this experimental method to test white button mushrooms and their impact on blood lipid levels and the inflammatory response. This dietary study involved preparation of two soups: a placebo, broth-based soup and one with one cup of white button mushrooms per cup of soup to provide one and a half cups of soup (and mushrooms) per day to each participant. The soup was prepared in The Kitchen Café at the ASU Downtown Campus (Phoenix, AZ).
After preparing the soup, the next goal was recruitment through listserv, local advertisements, flyers, and word of mouth of participants to test the overall plan. Over fifteen people responded; however, only one candidate met the inclusion criteria of someone at high risk of developing CVD and agreed to participate in the study. The participant visited the nutrition laboratory in downtown Phoenix (550 N. 5th Street). Anthropometric data and an initial blood draw were completed, and fourteen 1.5 cup containers of mushroom soup were dispensed to the participant. After two weeks, the individual returned and the same procedures were executed to include anthropometry and blood analysis. Even though the subject did not show changes in blood markers of CVD risk (lipids and inflammatory markers), the hypothesis for the thesis that the study design would be effective was accepted. Thus, the procedure was successful and validated and will be used in the future study.
The objective of this thesis was to establish protocols and a valid experimental design for testing whether dietary mushrooms could, in fact, be protective against CVD risk. Specifically, a case-study approach was used to validate this experimental method to test white button mushrooms and their impact on blood lipid levels and the inflammatory response. This dietary study involved preparation of two soups: a placebo, broth-based soup and one with one cup of white button mushrooms per cup of soup to provide one and a half cups of soup (and mushrooms) per day to each participant. The soup was prepared in The Kitchen Café at the ASU Downtown Campus (Phoenix, AZ).
After preparing the soup, the next goal was recruitment through listserv, local advertisements, flyers, and word of mouth of participants to test the overall plan. Over fifteen people responded; however, only one candidate met the inclusion criteria of someone at high risk of developing CVD and agreed to participate in the study. The participant visited the nutrition laboratory in downtown Phoenix (550 N. 5th Street). Anthropometric data and an initial blood draw were completed, and fourteen 1.5 cup containers of mushroom soup were dispensed to the participant. After two weeks, the individual returned and the same procedures were executed to include anthropometry and blood analysis. Even though the subject did not show changes in blood markers of CVD risk (lipids and inflammatory markers), the hypothesis for the thesis that the study design would be effective was accepted. Thus, the procedure was successful and validated and will be used in the future study.
ContributorsBratrud, Kathryn Michelle (Author) / Martin, Keith (Thesis director) / Appel, Christy (Committee member) / Shepard, Christina (Committee member) / Barrett, The Honors College (Contributor) / T. Denny Sanford School of Social and Family Dynamics (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2013-05
Description
Chronic diseases place a financial burden on the United States and claim the lives of nearly 2 million Americans every year. Among the chronic diseases that plague American people, type 2 diabetes is particularly prevalent and injurious. Thus, action is warranted to improve prevention and management of this disease. Nutrition plays a significant role in prevention and management of type 2 diabetes and other chronic diseases. Registered dietitians, as nutrition experts, are qualified to use medical nutrition therapy as a method of prevention and treatment for chronic diseases using a nutritional approach. However, there is no consensus as to which eating pattern is the most efficacious. The aim of this review of research was to examine how plant-based eating patterns impact chronic disease conditions, with an emphasis on type 2 diabetes mellitus, as compared to omnivorous eating patterns. A literature search was conducted through the ASU Library, PubMed, and CINAHL using terms related to plant-based diets and chronic diseases, such as type 2 diabetes. The results revealed that a plant-based eating pattern may be beneficial in the prevention and treatment of certain chronic diseases, such as type 2 diabetes. Specifically, adults who have type 2 diabetes and consume a plant-based diet may exhibit enhanced glycemic control as evidenced by less insulin resistance, increased incretin and insulin secretion, greater insulin sensitivity, and improved HbA1c levels. There is sufficient evidence for registered dietitians to recommend a plant-based approach to patients with type 2 diabetes who would like to achieve enhanced glycemic control.
ContributorsSneddon, Ashley (Author) / Mayol-Kreiser, Sandra (Thesis director) / Shepard, Christina (Committee member) / College of Health Solutions (Contributor, Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2021-05