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ABSTRACT The hormone leptin is an important regulator of body weight and energy balance, while nitric oxide (NO) produced in the blood vessels is beneficial for preventing disease-induced impaired vasodilation and hypertension. Elevations in the free radical superoxide can result in impaired vasodilation through scavenging of NO. Omega 3 is

ABSTRACT The hormone leptin is an important regulator of body weight and energy balance, while nitric oxide (NO) produced in the blood vessels is beneficial for preventing disease-induced impaired vasodilation and hypertension. Elevations in the free radical superoxide can result in impaired vasodilation through scavenging of NO. Omega 3 is a polyunsaturated fatty acid that is beneficial at reducing body weight and in lowering many cardiovascular risk factors like atherosclerosis. The present study was designed to examine the change in plasma concentrations of leptin, nitric oxide, and the antioxidant superoxide dismutase in addition to examining the association between leptin and NO in healthy normal weight adult female subjects before and following omega 3 intakes. Participants were randomly assigned to either a fish oil group (600 mg per day) or a control group (1000 mg of coconut oil per day) for 8 weeks. Results showed no significant difference in the percent change of leptin over the 8 week supplementation period for either group (15.3±31.9 for fish oil group, 7.83±27 for control group; p=0.763). The percent change in NO was similarly not significantly altered in either group (-1.97±22 decline in fish oil group, 11.8±53.9 in control group; p=0.960). Likewise, the percent change in superoxide dismutase for each group was not significant following 8 weeks of supplementation (fish oil group: 11.94±20.94; control group: 11.8±53.9; p=0.362). The Pearson correlation co-efficient comparing the percent change of both leptin and NO was r2= -0.251 demonstrating a mildly negative, albeit insignificant, relationship between these factors. Together, these findings suggest that daily supplementation with 600 mg omega 3 in healthy females is not beneficial for improving these cardiovascular risk markers. Future studies in this area should include male subjects as well as overweight subjects with larger doses of fish oil that are equivalent to three or more servings per week. The importance of gender cannot be underestimated since estrogen has protective effects in the vasculature of females that may have masked any further protective effects of the fish oil. In addition, overweight individuals are often leptin-resistant and develop impaired vasodilation resulting from superoxide-mediated scavenging of nitric oxide. Therefore, the reported antioxidant and weight loss properties of omega 3 supplementation may greatly benefit overweight individuals.
ContributorsAlanbagy, Samer (Author) / Sweazea, Karen (Thesis advisor) / Johnston, Carol (Committee member) / Shepard, Christina (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2014
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To date, there have not been any studies in a human population that explore the potential of vinegar ingestion in reducing visceral fat, a common yet serious metabolic disease risk factor. However, previous research in animal models exhibit promising findings, showing that vinegar is effective at reducing visceral fat. This

To date, there have not been any studies in a human population that explore the potential of vinegar ingestion in reducing visceral fat, a common yet serious metabolic disease risk factor. However, previous research in animal models exhibit promising findings, showing that vinegar is effective at reducing visceral fat. This is thought to be due to the activation of AMPK (adenosine monophosphate protein kinase) by acetic acid, the active ingredient in vinegar. The purpose of this study was to identify if this potentially groundbreaking relationship exists in human subjects. Healthy, nonsmoking, sedentary adults between the ages 18-45 y and a waist circumference measurement greater than or equal to 33 inches for women and 38 inches for men were recruited for this study. Twenty-three participants completed this 8-week, parallel arm, randomized control trial that tested the efficacy of red wine vinegar consumption (2 tablespoons red wine vinegar, twice per day, before a meal; providing 3.6 g acetic acid) against a placebo (1 apple cider vinegar pill, twice per day, before a meal; providing 0.0225 g acetic acid) for 8 weeks. Participants were randomized into either the vinegar (VIN) or control (CON) group after being stratified by age, gender, waist circumference, and weight. Results found that the VIN group experienced a 2% decrease in visceral fat (cm3, quantified by a DXA scan), but this change did not differ significantly from that of the CON group (p=0.256). The VIN group also experienced a slight decrease in insulin compared to the CON group, but this change was not significantly different than the control change (p=0.125). However, the change in HOMA-IR trended downward in the VIN group (-16%) as compared to the CON group (+9%) (p=0.079) with a large effect size, 0.153. Other parameters did not show statistically significant results between the groups. Further research is indicated in order to examine the potential of vinegar to reduce visceral fat.
ContributorsBaker, Olivia (Author) / Johnston, Carol (Thesis advisor) / Mayol-Kreiser, Sandra (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2018
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Turmeric is the bright yellow root that has been used as a spice, healing remedy, and textile dye. Previous studies have suggested that the most active ingredient in turmeric, curcumin, could reduce serum cholesterol concentration. However, most of these studies were conducted on animals and not many have been done

Turmeric is the bright yellow root that has been used as a spice, healing remedy, and textile dye. Previous studies have suggested that the most active ingredient in turmeric, curcumin, could reduce serum cholesterol concentration. However, most of these studies were conducted on animals and not many have been done on controlled human trials. This randomized, double-blinded, controlled crossover study evaluates the effects of turmeric on blood cholesterol concentrations including total cholesterol, LDL cholesterol, HLD cholesterol, and triglycerides. In this study, eight healthy participants between the ages of 18 and 45 were randomized to receive either 500mg capsules of turmeric or placebo for a period of three weeks. Following a wash-out period of five weeks, all participants were crossed over to the alternative treatment for another three weeks. After comparing the 3 week treatment and placebo phases, turmeric showed no significant effect on serum lipid concentrations. Furthermore, a slight increase in total cholesterol concentrations was observed following the turmeric phase when compared to the placebo phase.
ContributorsDo, Ngoc Bich Thi (Author) / Johnston, Carol (Thesis director) / Whisner, Corrie (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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The effects of iron and chromium blood concentrations have been linked to blood glucose control in diabetics. It is suggested that iron causes oxidative stress in the beta cells of the pancreas and adipocytes creating insulin insufficiency and resistance. Chromium is believed to increase the action of insulin

The effects of iron and chromium blood concentrations have been linked to blood glucose control in diabetics. It is suggested that iron causes oxidative stress in the beta cells of the pancreas and adipocytes creating insulin insufficiency and resistance. Chromium is believed to increase the action of insulin through its biologically active molecule chromodulin. Both of these mechanisms are not clear. This 20 week case study tests the feasibility of combining iron depletion therapy followed by chromium supplementation to improve insulin sensitivity. This single case study followed a protocol of two blood donations separated by eight weeks followed by chromium supplementation of 250 µg of chromium picolinate once a day four weeks after the second blood donation. Fasting blood draws were taken at baseline, post blood draws and pre and post chromium supplementation. Results were not promising for the first hypothesis of lowering HbA1c, but the results were promising for the second hypothesis of improving insulin sensitivity by lowering the HOMA score.
ContributorsJarrett, Nia (Author) / Johnston, Carol (Thesis advisor) / Lespron, Christy (Committee member) / Mayol-Kreiser, Sandra (Committee member) / Arizona State University (Publisher)
Created2015
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Background: Acetic acid in vinegar has demonstrated antiglycemic effects in previous studies; however, the mechanism is unknown.

Objective: To determine whether acetic acid dissociates in the addition of sodium chloride and describe a flavorful vinaigrette that maintains the functional properties of acetic acid.

Design: Phase I - Ten healthy subjects

Background: Acetic acid in vinegar has demonstrated antiglycemic effects in previous studies; however, the mechanism is unknown.

Objective: To determine whether acetic acid dissociates in the addition of sodium chloride and describe a flavorful vinaigrette that maintains the functional properties of acetic acid.

Design: Phase I - Ten healthy subjects (23-40 years) taste tested five homemade vinaigrette and five commercial dressings. Perceived saltiness, sweetness, tartness, and overall tasted were scored using a modified labeled affective magnitude scale. Each dressing was tested three times for pH with a calibrated meter. Phase II – Randomized crossover trial testing six dressings against a control dressing two groups of nine healthy adult subjects (18-52 years). Height, weight and calculated body mass index (BMI) were performed at baseline. Subjects participated in four test sessions each, at least seven days apart. After a 10-hour fast, participants consumed 38g of the test drink, followed by a bagel meal. Capillary blood glucose was obtained at fasting, and every 30 minutes over a 2-hour period the test meal.

Results: Dressing pH reduced as sodium content increased. In the intervention trials, no significant differences were observed between groups (p >0.05). The greatest reduction in postprandial glycemia (~21%) was observed in the dressing containing 200 mg of sodium. Effect size was large in both group 1 (η2=0.161) and group 2 (η2=0.577).

Conclusion: The inclusion of sodium into acetic acid may impair its ability to attenuate blood glucose after a meal.
ContributorsBonsall, Amber K (Author) / Johnston, Carol (Thesis advisor) / Mayol-Kreiser, Sandra (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2017
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There are limited studies exploring the direct relationship between coconut oil and cholesterol concentrations. Research in animals and a few intervention trials suggest that coconut oil increases the good cholesterol (high density lipoprotein, HDL) and thus reduces the risk of cardiovascular disease. Preliminary research at Arizona State University (ASU) has

There are limited studies exploring the direct relationship between coconut oil and cholesterol concentrations. Research in animals and a few intervention trials suggest that coconut oil increases the good cholesterol (high density lipoprotein, HDL) and thus reduces the risk of cardiovascular disease. Preliminary research at Arizona State University (ASU) has found similar results using coconut oil as a placebo, positive changes in HDL cholesterol concentrations were observed.

The goal of this randomized, double blind, parallel two arm study, was to further examine the beneficial effects of a 2g supplement of coconut oil taken each day for 8 weeks on cholesterol concentrations, specifically the total cholesterol to HDL cholesterol ratio, compared to placebo.

Forty-two healthy adults between 18-40 years of age, exercising less than 150 minutes each week, non smoking, BMI between 22-35 and not taking any medications that could effect blood lipids were recruited from the ListServs at ASU. Participants were randomized to receive either a placebo capsule of flour or a coconut oil capsule (Puritan’s Pride brand, coconut oil softgels, 2g each) and instructed to take the capsules for 8 weeks.

Results indicated no significant change in total cholesterol to HDL ratio between baseline and 8 weeks in the coconut oil and placebo groups (p=0.369), no significant change in HDL (p=0.648), no change in LDL (p=0.247), no change in total cholesterol (p=0.216), and no change in triglycerides (p=0.369).

Blood lipid concentrations were not significantly altered by a 2g/day dosage of coconut oil over the course of 8 weeks in healthy adults, and specifically the total cholesterol to HDL ratio did not change or improve.
ContributorsShedden, Rachel (Author) / Johnston, Carol (Thesis advisor) / Lespron, Christy (Committee member) / Shepard, Christina (Committee member) / Arizona State University (Publisher)
Created2017
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Description
Curcumin is an active ingredient of Curcuma longa (Turmeric) and is studied extensively for its antioxidant, anti-inflammatory, anti-bacterial, anti-viral, and anti-cancer properties. The purpose of this study was to examine the effects of turmeric on blood glucose and plasma insulin levels. The study utilized a placebo-controlled, randomized cross-over

Curcumin is an active ingredient of Curcuma longa (Turmeric) and is studied extensively for its antioxidant, anti-inflammatory, anti-bacterial, anti-viral, and anti-cancer properties. The purpose of this study was to examine the effects of turmeric on blood glucose and plasma insulin levels. The study utilized a placebo-controlled, randomized cross-over design with participants serving as their own control. Eight glucose tolerant healthy participants completed the full study. Three-weeks washout period was kept in between six-weeks. Prior to the test meal day, participants were asked to eat a bagel with their evening dinner. During the day of the test meal, participants reported to the test site in a rested and fasted state. Participants completed mashed potato meal tests with 500 mg of turmeric powder or placebo mixed in water, followed by 3 weeks of 500 mg turmeric or placebo supplement ingestion at home. During this visit blood glucose finger picks were obtained at fasting, 30, 60, 90, and 120 min post-meal. Blood plasma insulin at fasting and at 30 min after the test meal were also obtained. During week 4, participants reported to the test site in a rested and fasted state where fasting blood glucose finger pricks and blood plasma insulin were measured. During week 5 to 7, participants were given a washout time-period. During week 8, entire process from week 1 to 4 was repeated by interchanging the groups. Compared to placebo, reduction in postprandial blood glucose and insulin response were non-significant after ingestion of turmeric powder. Taking turmeric for 3 weeks had no change in blood glucose and insulin levels. However, taking turmeric powder supplements for 3 weeks, showed a 4.4% reduction in blood glucose. Change in insulin at 30 min were compared with baseline insulin level showing no significant change between placebo and turmeric group. Fasting insulin after 3-weeks consumption of turmeric did not show any significant change, but showed a larger effect size (0.08). Future research is essential to examine the turmeric powder supplement benefits over a long period of time in healthy adults and whether it is beneficial in preventing the occurrence of type 2 diabetes.
ContributorsOza, Namrata (Author) / Johnston, Carol (Thesis advisor) / Mayol-Kreiser, Sandra (Committee member) / Lespron, Christy (Committee member) / Arizona State University (Publisher)
Created2017