Browsing by Author "Dawson, John A. (TTU)"
Now showing 1 - 8 of 8
- Results Per Page
- Sort Options
Item A randomized cross-over trial to determine the effect of a protein vs. carbohydrate preload on energy balance in ad libitum settings(2019) Gibson, Madeline J.; Dawson, John A. (TTU); Wijayatunga, Nadeeja N. (TTU); Ironuma, Bridget (TTU); Chatindiara, Idah; Ovalle, Fernando; Allison, David B.; Dhurandhar, Emily J. (TTU)Background: Although high protein diets have been tested in controlled environments for applications to weight management, it is not understood if adding high protein foods to the diet would impact ad libitum energy balance in the absence of other lifestyle changes. Methods: This double-blinded randomized crossover trial compared the effects of a protein shake (PS) to a carbohydrate shake (CS), consumed prior to each major meal to equate to 20% of total energy needs over the course of the day, on energy balance over two 5-day treatment periods in healthy adults with BMI 20-30 kg/m2. Tri-axial accelerometers estimated physical activity energy expenditure. Ad libitum energy intake was measured in a laboratory kitchen. Results: Energy balance was positive during both treatment periods but was not different between periods. There were no interactions between treatment and preload caloric dose or treatment and BMI status on energy balance. Satiety ratings did not differ for any pairwise comparisons between treatment and caloric dose. Controlling for gender and basal metabolic rate, thermic effect of food was greater for PS than CS. Conclusions: Preload periods significantly altered the macronutrient composition of the overall diet. This study found limited evidence that carbohydrate or protein preloads have differential effects on energy balance in short-term ad libitum settings.Item Both dietary ratio of n-6 to n-3 fatty acids and total dietary lipid are positively associated with adiposity and reproductive health in zebrafish(2020) Fowler, Lauren A.; Dennis-Cornelius, Lacey N.; Dawson, John A. (TTU); Barry, Robert J.; Davis, James L.; Powell, Mickie L.; Yuan, Yuan; Williams, Michael B.; Makowsky, Robert; D'Abramo, Louis R.; Watts, Stephen A.Background: Controversial findings have been reported in human and animal studies regarding the influence of n-6 (ω-6) to n-3 (ω-3) fatty acid ratios on obesity and health. Two confounding factors may be related to interactions with other dietary lipid components or sex-specific differences in fatty acid metabolism. Objective: This study investigated main and interactive effects of total dietary lipid, ratio of n-6 to n-3 fatty acids, and sex on growth, adiposity, and reproductive health in wild-type zebrafish. Methods: Male and female zebrafish (3 wk old) were fed 9 diets consisting of 3 ratios of n-6 to n-3 fatty acids (1.4:1, 5:1, and 9.5:1) varied within 3 total lipid amounts (80, 110, and 140 g/kg) for 16 wk. Data were then collected on growth, body composition (determined by chemical carcass analysis), and female reproductive success (n = 32 breeding events/diet over 4 wk). Main and interactive effects of dietary lipid and sex were evaluated with regression methods. Significant differences within each dietary lipid component were relative to the intercept/reference group (80 g/kg and 1.4:1 ratio). Results: Dietary lipid and sex interacted in their effects on body weight (P = 0.015), total body length (P = 0.003), and total lipid mass (P = 0.029); thus, these analyses were stratified by sex. Female spawning success decreased as dietary total lipid and fatty acid ratio increased (P = 0.030 and P = 0.026, respectively). While total egg production was not associated with either dietary lipid component, females fed the 5:1 ratio produced higher proportions of viable embryos compared with the 1.4:1 ratio [median (95% CI): 0.915 (0.863, 0.956) vs 0.819 (0.716, 0.876); P < 0.001]. Conclusions: Further characterization of dietary lipid requirements will help define healthy balances of dietary lipid, while the sex-specific responses to dietary lipid identified in this study may partially explain sex disparities in the development of obesity and its comorbidities.Item A Culturally Sensitive and Theory-Based Intervention on Prevention and Management of Diabetes: A Cluster Randomized Control Trial(2022) Githinji, Phrashiah (TTU); Dawson, John A. (TTU); Appiah, Duke (TTUHSC); Rethorst, Chad DType 2 diabetes is an emerging concern in Kenya. This clustered-randomized trial of peri-urban communities included a theory-based and culturally sensitive intervention to improve diabetes knowledge, health beliefs, dietary intake, physical activity, and weight status among Kenyan adults. Those in the intervention group (IG) received a culturally sensitive diabetes education intervention which applied the Health Belief Model in changing knowledge, health beliefs and behavior. Participants attended daily education sessions for 5 days, each lasting 3 h and received mobile phone messages for an additional 4 weeks. The control group (CG) received standard education on COVID-19. Data was collected at baseline, post-intervention (1 week), and follow-up assessment (5 weeks). Linear mixed effect analysis was performed to assess within and across group differences. Compared to the control, IG significantly increased diabetes knowledge (p < 0.001), health beliefs including perceived susceptibility (p = 0.05), perceived benefits (p = 0.04) and self-efficacy (p = 0.02). IG decreased consumption of oils (p = 0.03), refined grains (p = 0.01), and increased intake of fruits (p = 0.01). Perceived barriers, physical activity, and weight status were not significantly different between both groups. The findings demonstrate the potential of diabetes education in improving diabetes knowledge, health beliefs, and in changing dietary intake of among adults in Kenya.Item Effect of potatoes as part of the DASH diet on blood pressure in individuals with and without type 2 diabetes: A randomized controlled trial(2024) Galyean, Shannon (TTU); Sawant, Dhanashree (TTU); Childress, Allison (TTU); Alcorn, Michelle (TTU); Dawson, John A. (TTU)This randomized controlled trial evaluated different cooking methods of potatoes as part of the DASH diet on blood pressure (BP) and anthropometrics in people with and without type 2 diabetes (T2D). Participants were randomized into DASH-FP (fried potatoes), DASH-NFP (non-fried potatoes) or DASH-NP (no potatoes) groups. BP, weight, waist circumference and body composition were measured. Change outcomes from baseline to 6 weeks showed no significant difference in the study outcomes, including diastolic BP (p = 0.12), systolic BP (p = 0.26), body weight (p = 0.11), waist circumference (p = 0.86) and body composition (p = 0.57) within study groups. A significant group T2D status interaction was found for waist circumference (p = 0.036). Results from pairwise comparisons between the groups for all outcomes were not significant; however, a positive trend was seen in DASH-NFP and DASH-FP diet groups in BP and anthropometrics. Individuals with and without T2D that consumed potatoes and the DASH diet did not significantly change BP and anthropometrics by six weeks. Slight improvements in BP and anthropometrics were seen in non-fried and fried potato groups. This helps future investigations of popular foods for people with chronic conditions that can be incorporated in a healthy eating pattern. Clinical Trials.gov ID: NCT05589467; 9/16/2022.Item Effectiveness of a short-Term soy nutrition education intervention on nutrition knowledge and self-efficacy scores of rural elderly Zambian women(2023) Mukherjee, Upasana; Dawson, John A. (TTU); Chalwe, Joseph Musonda; Oldewage-Theron, Wilna (TTU)BACKGROUND: Women are at most risk for chronic diseases which can be prevented by healthy dietary choices. Evidence exists that nutrition education interventions (NEIs) are effective in educating community-dwelling women to modify their behavior for better health outcomes. OBJECTIVES: The objectives of this study were to implement a need-based, tailored NEI and evaluate its effectiveness in improving nutrition and soy knowledge and self-efficacy of participants in the intervention group compared to a control group. METHODS: A quasi-experimental pre-post-study design was used in a convenience sample of 149 women from the copper belt region of Zambia. The health belief model (HBM) informed the NEI, which consisted of six lessons, three cooking demonstrations, and an illustrative recipe book. Nutrition and soy knowledge scores and self-efficacy scores were evaluated using validated and reliable questionnaires. Data were analyzed using IBM SPSS software, version 26, and mean change scores in knowledge and self-efficacy were compared between the intervention and control groups. RESULTS: The average improvement in the scores for total nutrition knowledge and all six sub-sections of knowledge was significantly higher in the intervention group compared to the control group. The mean total self-efficacy score for the intervention group improved significantly (p=5.7767e-20) from a pre-intervention score of 29.9±7.4 to 57.3±7.0 after the implementation of the NEI. No significant improvement (p=0.904) in the control group was observed. CONCLUSIONS: A short-Term, multi-component NEI was effective in improving the nutrition and soy knowledge and soy cooking self-efficacy of the participants in the intervention group.Item Errors in the implementation, analysis, and reporting of randomization within obesity and nutrition research: a guide to their avoidance(2021) Vorland, Colby J.; Brown, Andrew W.; Dawson, John A. (TTU); Dickinson, Stephanie L.; Golzarri-Arroyo, Lilian; Hannon, Bridget A.; Heo, Moonseong; Heymsfield, Steven B.; Jaywardene, Wasantha P.; Kahathuduwa, Chanaka N. (TTUHSC); Keith, Scott W.; Oakes, J. Michael; Tekwe, Carmen D.; Thabane, Lehana; Allison, David B.Randomization is an important tool used to establish causal inferences in studies designed to further our understanding of questions related to obesity and nutrition. To take advantage of the inferences afforded by randomization, scientific standards must be upheld during the planning, execution, analysis, and reporting of such studies. We discuss ten errors in randomized experiments from real-world examples from the literature and outline best practices for their avoidance. These ten errors include: representing nonrandom allocation as random, failing to adequately conceal allocation, not accounting for changing allocation ratios, replacing subjects in nonrandom ways, failing to account for non-independence, drawing inferences by comparing statistical significance from within-group comparisons instead of between-groups, pooling data and breaking the randomized design, failing to account for missing data, failing to report sufficient information to understand study methods, and failing to frame the causal question as testing the randomized assignment per se. We hope that these examples will aid researchers, reviewers, journal editors, and other readers to endeavor to a high standard of scientific rigor in randomized experiments within obesity and nutrition research.Item Roux-en-Y gastric bypass surgery alters serum metabolites and fatty acids in patients with morbid obesity(2018) Wijayatunga, Nadeeja N. (TTU); Sams, Valerie G.; Dawson, John A. (TTU); Mancini, Matthew L.; Mancini, Gregory J.; Moustaid-Moussa, Naima (TTU)Aim: Bariatric surgery induces significant weight loss, increases insulin sensitivity, and reduces mortality, but the underlying mechanisms are not clear. It was hypothesized that Roux-en-Y gastric bypass (RYGB) surgery improves metabolic profile along with weight loss. The objective of this pilot study was to evaluate changes in serum metabolites and fatty acids (FA) at 2 weeks and 6 months after RYGB. Materials and Methods: Serum samples were collected pre-surgery, at 2 weeks and 6 months post-surgery from 20 patients undergoing RYGB surgery. Serum non-esterified free FA (NEFA) were measured. Serum metabolites and FA were measured using nuclear magnetic resonance spectroscopy and improved direct fatty acid methyl ester synthesis and the gas chromatography/mass spectrometry method, respectively, in subjects who completed follow-up at 6 months (n = 8). Results: Mean (standard deviation) percent total weight loss was 6.70% (1.7) and 24.91% (6.63) at 2 weeks (n = 15) and 6 months (n = 8) post-surgery, respectively. NEFA were significantly reduced at 6 months post-surgery (P = 0.001, n = 8). Serum branched chain amino acids, 2-aminobutyrate, butyrate, 2-hydroxybutyrate, 3-hydroxybutyrate, acetone, 2-methylglutarate, and 2-oxoisocaproate were significantly reduced, while serum alanine, glycine, pyruvate, and taurine were significantly elevated at 6 months post-surgery compared with pre-surgery (n = 8, P < 0.05). Also, serum FA C10:0, C13:0, C14:0, C15:0, and C18:0 increased significantly (n = 8, P < 0.05) by 6 months post-surgery. Conclusions: Changes in serum metabolites and FA at 6 months post-RYGB surgery in this pilot study with limited number of participants are suggestive of metabolic improvement; larger studies are warranted for confirmation.Item Transdermal Delivery of Metformin Using Dissolving Microneedles and Iontophoresis Patches for Browning Subcutaneous Adipose Tissue(2022) Abbasi, Mehrnaz (TTU); Fan, Zhaoyang; Dawson, John A. (TTU); Wang, Shu (TTU)Obesity is a serious public health problem that is strongly associated with increased multiple comorbidities such as diabetes, cardiovascular disease, and some types of cancer. While current anti-obesity treatments have various issues, locally transforming energy-storing white adipose tissue (WAT) into energy-burning brown-like/beige adipose tissue, the so-called browning of WAT, has been suggested to enhance obesity treatment efficiency with minimized side effects. Metformin is a first-line antidiabetes drug and a potent activator of AMP-activated protein kinase. Emerging evidence has suggested that metformin might enhance energy expenditure via the browning of WAT and hence reduce body weight. Subcutaneous WAT is easier to access and has a stronger browning potential than other WAT depots. In this study, we used dissolvable poly (lactic-co-glycolic acid) microneedles (MN) to deliver metformin to the subcutaneous WAT in obese C57BL/6J mice with the assistance of iontophoresis (INT), and then investigated metformin-induced WAT browning and its subsequent thermogenesis effects. Compared with MN alone or INT alone, MN + INT had better anti-obesity activity, as indicated by decreasing body weight and fat gain, increased energy expenditure, decreased fat pad size, and improved energy metabolism through the browning of WAT. Browning subcutaneous WAT by delivering metformin and other browning agents using this MN + INT approach might combat obesity in an effective, easy, and safe regimen.