<p> Parent income and educational attainment (EA) influence children&rsquo;s eating behaviors (EB). Psychological distress and socioeconomic disadvantage can trigger maladaptive EB that cause obesity (Hemmingson, 2014). Associations between Latino and African American (AA) parents&rsquo; income and EA with the child&rsquo;s EB and psychological distress were explored. Baseline data for 79 AA and Latina 8-11 year old girls were collected via self-report surveys and 24-hour recalls; parent data was derived from demographic forms. T-tests, one-way independent ANOVA, and correlations assessed relationships. Children&rsquo;s total fat intake differed by EA (<i>p</i>=.001) and income (<i> p</i>=.022). Total sugar intake (<i>p</i>=.011) differed by income. Fruit intake differed by income level <i>F</i>(2, 47)=4.93, <i> p</i>=.011. Number of fruit servings was inversely correlated with children&rsquo;s depressive symptoms (DS; <i>p</i>=.009) and trait anxiety (TA; <i> p</i>=.018). Emotional eating (EE) was positively related to DS (<i> p</i>&lt;.001), TA (<i>p</i>&lt; .001), and perceived stress (PS; <i>p</i>&lt;.001). Findings indicate that higher parent EA and income are associated with higher fat intake in children; higher income was associated with higher sugar intake. Fruit consumption seems to decrease with lower income, and higher DS and TA. Further, increased DS, TA, and PS are related to increased EE. Findings are contrary to expectations that poverty and low-education are associated with poor eating habits.</p>

Le but de cette étude consiste à démontrer l’impact positif d’une supplémentation en glutamine chez des nageurs élites, afin d’améliorer le statut immunitaire et d’évaluer si les changements plasmatiques de la glutamine peuvent expliquer l’incidence d’infections des voies respiratoires (IVRS). En parallèle, ce projet évalue si les apports alimentaires influencent la glutamine plasmatique et l’incidence d’IVRS. L’étude s’est effectuée auprès de 14 athlètes élites (8 hommes, 6 femmes). Chaque athlète a participé aux deux conditions expérimentales : un supplément de glutamine et une solution placebo isocalorique. Les périodes de supplémentation se déroulaient sur sept jours, incluant trois journées consécutives de compétition. Le profil hématologique, après les compétitions, montre qu’un supplément de glutamine n’améliore pas significativement la concentration plasmatique en glutamine ni les niveaux de cytokines comparativement à une solution placebo. Bien que les résultats soient semblables sous les deux conditions, les niveaux post-compétition ont tendance à être supérieurs aux valeurs pré-supplémentation, lorsqu’un apport exogène en glutamine est fourni à l’organisme alors que les concentrations plasmatiques de glutamine tendent à diminuer lorsqu’une solution placebo est administrée (p=0.067). L'incidence d’IVRS ne peut être expliquée par une faible concentration plasmatique de glutamine ni par un apport exogène de glutamine. On observe cependant une augmentation d’IVRS suite aux compétitions, soient de 8 athlètes pour le groupe placebo contre 3 au groupe glutamine. Les athlètes atteints d'IVRS semblent consommer moins d'énergie totale (kcal) et de protéines que les athlètes sains (p=0.060). Les résultats obtenus ne démontrent pas qu’une supplémentation en glutamine améliore le profil immunitaire et ne prévienne l’incidence d’IVRS, mais ils soulèvent l’hypothèse qu’un apport exogène en glutamine stabilise les niveaux plasmatiques de glutamine, permettant aux athlètes de poursuivre leurs entraînements et de récupérer efficacement. / The purposes of this study were to determine the positive impacts of glutamine supplementation upon immune system status and to determine whether changes in plasma glutamine relate to the appearance of upper respiratory tract infections (URTI) in elite swimmers. Furthermore, this study evaluated dietary intakes and its influence on immune parameters and URTI incidence. Fourteen athletes (8 men, 6 women) took part of the study. Each athlete participated in both experimental conditions: glutamine supplement and an isocaloric solution placebo. The supplementation period lasted seven day, including three consecutive competing days. Post competing hematologic profils of swimmers show that glutamine supplement does not significantly improve plasma glutamine neither cytokines levels, compared to a placebo solution. Even if plasma glutamine concentrations are similar with both conditions, the post competiting levels tend to be higher than pre competing values, when glutamine is supplemented. Futhermore, plasma glutamine levels show a decreasing trend under control conditions (p=0.060). In this study, URTI can not be explained by low plasma glutamine or supplemented glutamine. However, URTI incidence is higher after competitions, where 8 athletes showed symptoms (control group) and 3 only in the experimental group. Athletes with URTI seem to consume less energy and proteins than healthy athletes (p=0.060). These data does not suggest that glutamine supplementation improves immune function or prevents URTI in highly trained swimmers during competition. However, results support the hypothesis that exogenous glutamine stabilizes plasma glutamine levels, allowing athletes to tolerate training workload and recover properly.

La vitamine K fait l’objet d’un intérêt croissant en regard du rôle qu’elle peut jouer dans la santé humaine hormis celui bien établi dans la coagulation sanguine. De plus en plus d’études expérimentales lui confèrent des fonctions dans le système nerveux central, particulièrement dans la synthèse des sphingolipides, l’activation de la protéine vitamine K-dépendante Gas6 et la protection contre les dommages oxydatifs. Toutefois, il demeure beaucoup moins bien établi si la perturbation de ces fonctions peut conduire à des déficits cognitifs. L’objectif principal de cette thèse est de vérifier l’hypothèse selon laquelle le statut vitaminique K des personnes âgées en santé est un déterminant de la performance cognitive. En vue de la réalisation de cet objectif, une meilleure compréhension des indicateurs du statut vitaminique K s’avérait nécessaire. Chacune des études présentées vise donc un objectif spécifique : 1) évaluer le nombre de rappels alimentaires de 24 heures non consécutifs nécessaire pour mesurer l’apport habituel de vitamine K des personnes âgées; 2) évaluer la valeur d’une seule mesure de la concentration sérique de vitamine K comme marqueur de l’exposition à long terme; et 3) examiner l’association entre le statut vitaminique K et la performance cognitive des personnes âgées en santé de la cohorte québécoise NuAge. Trois dimensions cognitives ont été évaluées soient la mémoire épisodique verbale et non-verbale, les fonctions exécutives et la vitesse de traitement de l’information. Cette thèse présente la première étude appuyant l’hypothèse d’un rôle de la vitamine K dans la cognition chez les personnes âgées. Spécifiquement, la concentration sérique de vitamine K a été associée positivement à la performance en mémoire épisodique verbale, et plus particulièrement au processus de consolidation de la trace mnésique. En accord avec les travaux chez l’animal et l’action de la protéine Gas6 dans l’hippocampe, un rôle spécifique de la vitamine K à l’étape de consolidation est biologiquement plausible. Aucune association significative n’a été observée avec les fonctions exécutives et la vitesse de traitement de l’information. Parallèlement, il a été démontré qu’une mesure unique de la concentration sérique de vitamine K constitue une mesure adéquate de l’exposition à long terme à la vitamine K. De même, il a été établi que six à 13 rappels alimentaires de 24 heures sont nécessaires pour estimer précisément l’apport de vitamine K des personnes âgées en santé. Collectivement, les résultats de ces deux études fournissent des informations précieuses aux chercheurs permettant une meilleure interprétation des études existantes et une meilleure planification des études futures. Les résultats de cette thèse constituent une avancée importante dans la compréhension du rôle potentiel de la vitamine K dans le système nerveux central et renforce la nécessité qu’elle soit considérée en tant que facteur nutritionnel du vieillissement cognitif, en particulier chez les personnes traitées par un antagoniste de la vitamine K. / There is an increasing interest in the potential roles of vitamin K in human health aside from the one well established in blood clotting. Notably, a growing number of experimental studies show that vitamin K has biological functions in the central nervous system, particularly in the synthesis of sphingolipids, the activation of the vitamin K-dependent protein Gas6, and the prevention of oxidative damage. However, it remains uncertain whether the disruption of these functions can lead to cognitive deficits. The main objective of this thesis is to test the hypothesis that vitamin K status is a determinant of cognitive performance in healthy older adults. In order to achieve this goal, a better understanding of vitamin K status indicators was needed. Accordingly, three studies are presented each aiming at a specific objective: 1) estimate the number of non-consecutive 24-hour dietary recalls needed to assess usual vitamin K intake; 2) determine whether a single measurement of serum vitamin K concentration is an adequate indicator of long-term vitamin K exposure; and 3) examine the association between vitamin K status and cognitive performance in healthy older adults from the Québec NuAge Study. Three cognitive domains were assessed namely verbal and non-verbal episodic memory, executive functions, and speed of processing. This thesis presents the first study providing support for a role of vitamin K in cognition in older adults. Specifically, serum vitamin K concentration was positively associated with performance in verbal episodic memory, particularly in the consolidation process of the memory trace. Consistent with rodent studies and the action of the protein Gas6 in the hippocampus, a specific role of vitamin K in memory consolidation is biologically plausible. No significant association was observed with executive functions and speed of processing. Additionally, it was established that a single measurement of serum vitamin K concentration is adequate for assessing long-term vitamin K exposure in healthy older adults. Similarly, it was determined that six to 13 24-hour dietary recalls are needed to accurately assess usual vitamin K intake. Collectively, both studies provide valuable information to researchers for better interpretation of existing studies and planning future ones. Results from this thesis constitute an important step in the understanding of the potential role of vitamin K in the central nervous system, emphasizing the need to consider this micronutrient as a nutritional factor of cognitive aging, especially among those treated with vitamin K antagonists.

Doctor of Philosophy / Department of Human Nutrition / Mark D. Haub / Objective: The objective was to compare the postprandial glycemic and insulinemic responses to nutrition bars containing either cross-linked RS type 4 (RS4[subscript]XL) or standard wheat starch in normoglycemic adults (n=13; age= 27±5 yr; BMI=25±3 kg/m²). Methods: Volunteers completed three trials during which they consumed a glucose beverage (GLU), a puffed wheat control bar (PWB), and a bar containing RS4[subscript]XL matched for available carbohydrate content. Serial blood samples were collected over two hours and glucose and insulin concentrations were determined and the incremental area under the curve (iAUC) was calculated. Results: The RS4[subscript]XL peak glucose and insulin concentrations were lower than the GLU and PWB (p<0.05). The iAUC for glucose and insulin were lower following ingestion of RS4[subscript]XL compared with the GLU and PWB trials. Conclusions: These data illustrate, for the first time, that directly substituting standard starch with RS4[subscript]XL, while matched for available carbohydrates, attenuated postprandial glucose and insulin levels in humans. It remains to be determined whether this response was due to the dietary fiber and/or resistant starch aspects of the RS4[subscript]XL bar. Keywords: insulin sensitivity, diabetes, dietary fiber, prebiotic, glycemic index

From 1996 to 2002, the Democratic Republic of Congo (DRC) experienced numerous outbreaks of war. Kinshasa, the Capital, was isolated from its main sources of local food supply which led to a sharp deterioration of the life quality. In 2003, with the Sun City Accord signed formally ending the protracted war, the political and economic situation of the country seemed better. Yet, the household food situation did not seem to improve This study aimed to increase the general understanding of food insecurity at the household level. The objectives were to determine households' food-insecure based on household socioeconomic and demographic characteristics, to identify coping strategies used by households to manage the food crisis, and to assess differences between the two time periods A total of 1,591 households from two selected health zones of Kinshasa were surveyed in 2001 and 2004 using a multiple stage-cluster design. A 16-question measure was developed using a summative scale to capture the food security status. Two binary logistic regressions were run to predict food insecurity and identify coping strategies. Interactions were tested in the models to assess differences between the two time periods. Comparisons of proportions and odds ratio were also computed Households whose chief had none, primary or secondary levels of education, and households with little crafts or jobs as main source of incomes were food-insecure. Change of meal composition, food aid from nutritional centers, and reduction of persons in charge were the main coping strategies used by households food-insecure. No interaction tested in the two models was significant. Households were more likely to be food-insecure during the war period, and the prevalence of determinants and that of coping strategies were also higher during the war period These research findings provided a better and in-depth understanding of household food insecurity regarding determinants and coping strategies. The relationships between determinants as well as coping strategies and food insecurity were consistent across time, although the observed differences between the two contexts. Political and economic stability of the country should be ensured, salaries paid regularly, post primary education promoted, and food program interventions implemented for sustainable development / acase@tulane.edu

acase@tulane.edu

acase@tulane.edu

acase@tulane.edu

acase@tulane.edu

Using data from the Ethiopia Title II Food Security Baseline Survey conducted in 1997 this study explored the targeting performance and nutritional impact of food for work (FFW) activities conducted by seven nongovernmental agencies (called Cooperating Sponsors) funded by the Title II food aid program. A total of 52,856 individuals in 9682 households were interviewed in the fifty Ethiopian weredas where the Title II Cooperating Sponsors were implementing development programs Significant differences in malnutrition prevalence rates and poverty levels were found between areas targeted for FFW activities and areas not targeted. In the weredas targeted for FFW activities there were nearly 4% more stunted children and almost 6% more underweight children than in non-targeted areas. Within weredas targeted for food for work activities, no differences were found in malnutrition or poverty levels between households that participated and did not participate in FFW activities Using logistic regression analysis, models were created that controlled for factors explaining variance in stunting and underweight malnutrition rates of children 6--59 months old in the sample. The number of rations received by households was forced in to see if it significantly explained any additional variation in stunting or underweight prevalences. Despite submitting rations at different times, using different cutoffs of the dependent variable, and using rations in a variety of categorical forms, the number of rations received by households during the year was not a significant factor in explaining stunting or underweight status. While the non-selection of many households with malnourished children from FFW activities decreased the chance of reduced malnutrition rates, the complete insignificance of rations in the model implied that in general, food rations from FFW do not have an impact on the nutritional status of children / acase@tulane.edu