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Scholarly Works (24 results)

  • Thesis
  • Peer Reviewed
UC Irvine Electronic Theses and Dissertations (2023)

Dietary patterns and food choices play a significant role in the health of communities and individuals. Evidence suggests that while college students do not experience a high prevalence of chronic illness, their diet quality is extraordinarily poor. This dissertation performed a systematic review and conducted a randomized controlled trial to evaluate the impact and effect of simple and personalized diet-related behavioral interventions on diet quality among young adults, specifically those who are attending college. First, a systematic review was conducted to identify and synthesize the findings of previously published studies among young adults, aged 18-35 years, which tested the effects of easy-to-learn interventions when compared to passive or alternative treatments on overall diet quality or constituents of diet quality. Next, cross-sectional analysis of baseline data from a behavioral intervention study for improving diet quality in college students was conducted with the goal of identifying associations between perceived stress and diet quality, and the moderating role of food security status. Finally, a randomized controlled trial investigated the effects of a simple and individually modifiable intervention on the diet quality of college students. Participants in the control group were asked to read and consider the principles of the dietary guidelines for Americans, and participants in the experimental group selected two dietary change statements which were printed into keychain tags and carried on their person to provide a consistent reminder of their desired dietary improvement. Five of the nine studies included in the systematic review reported significant improvement to the selected dietary outcome between groups. Four of these studies used an implementation intentions approach that had participants write out a simple dietary behavior directive and carry it with them for the study duration, and three reported significant differences between groups. The average Cohen’s d effect size for all included studies was 0.26. Next, results from the cross-sectional analysis reported no significant associations between perceived stress and HEI-2020 or any component of diet quality, however, there were significant interactive effects for food security and perceived stress on total vegetable and total protein component scores. Lastly, results of the trial intervention reported no significant differences within or between the control and experimental groups at any time point for HEI-2020 total or component scores, with the exception an increase in total vegetable score from baseline to week 4 in the control group only. Despite the non-significant findings, the majority of the participants reported satisfaction with the intervention’s ease and utility. Prior evidence suggests that small-scale and individualized efforts can play a role in promoting healthy behaviors in college students. Additional efforts to improve diet quality should consider both the personal and structural circumstances that students encounter during their time in academia.

    • Article
    • Peer Reviewed
    UC Irvine Previously Published Works (2020)
    There is inconsistent evidence that healthy dietary interventions can effectively mitigate the risk of adverse outcomes associated with elevated insulin resistance in pregnancy, suggesting that other moderating factors may be at play. Maternal psychological state is an important factor to consider in this regard, because stress/mood state can directly influence glycemia and a bidirectional relationship may exist between nutrition and psychological state. The objective of this study was to examine the interaction between maternal negative affect and diet quality on third trimester insulin resistance. We conducted a prospective longitudinal study of N = 203 women with assessments in early and mid-pregnancy, which included an ecological momentary assessment of maternal psychological state, from which a negative affect score (NAS) was derived, and 24-h dietary recalls, from which the Mediterranean Diet Score (MDS) was computed. The homeostasis model assessment of insulin resistance (HOMA-IR) was computed from third trimester fasting plasma glucose and insulin values. Early pregnancy MDS was inversely associated with the HOMA-IR, but this did not maintain significance after adjusting for covariates. There was a significant effect of the mid-pregnancy MDS*NAS interaction term with the HOMA-IR in the adjusted model, such that a higher negative affect was found to override the beneficial effects of a Mediterranean diet on insulin resistance. These results highlight the need to consider nutrition and affective state concurrently in the context of gestational insulin resistance.
      Cover page: The Effect of a Maternal Mediterranean Diet in Pregnancy on Insulin Resistance is Moderated by Maternal Negative Affect.
      • Article
      • Peer Reviewed
      UC Irvine Previously Published Works (2023)

      Introduction

      Improving the diet quality of young adults may support chronic disease prevention. The approaches used and efficacy of promoting small dietary behavior changes through easy-to-learn (ETL) interventions (requiring no more than 1 hour to teach the behavior) among young adults have not yet been systematically reviewed.

      Methods

      Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, 2 independent electronic searches across 6 databases were conducted to identify any articles describing ETL interventions among young adults (aged 18-35 years) and reporting dietary intake outcomes.

      Results

      Among 9,538 articles identified, 9 studies met eligibility criteria. Five studies reported significant improvement in the selected dietary outcome. Of these, 3 studies used an implementation intentions approach, in which participants were given or asked to write out a simple dietary behavior directive and carry it on their person. Less than half of included studies were rated as positive for overall quality.

      Discussion

      The available evidence suggests that ETL interventions targeting the dietary behaviors of young adults may be effective in improving dietary intake. Limitations of included studies were lack of follow-up after the intervention period and low generalizability.

      Implications for research and practice

      Further dietary intervention studies targeting young adults should systematically evaluate the efficacy of ETL intervention approaches among diverse samples.
        Cover page: Systematic Review of Easy-to-Learn Behavioral Interventions for Dietary Changes Among Young Adults
        • Multimedia
        • Peer Reviewed
        ICTS Publications (2018)

        Introduction:

        Excess inflammation during pregnancy may exert adverse effects on fetal development and birth outcomes, including prematurity, intrauterine growth restriction, and preeclampsia. Maternal nutrition and stress are two of the most frequently but independently studied factors for their influence on prenatal inflammatory status, but their interaction in the context of pregnancy has been significantly understudied.

        The Dietary Inflammatory Index (DII) is a validated method to characterize and quantify the cumulative inflammatory potential of an individual diet,1 and has been previously used in prenatal populations.2,3 Ecological Momentary Assessment (EMA) methods are an effective way to assess psychosocial states in real-time, ambulatory, naturalistic settings, reducing the potential for recall and saliency bias associated with traditional retrospective questionnaires.4 

        Objective: The aim of this study is to investigate the combined effects of perceived stress (PSS) and dietary inflammatory index (DII) across pregnancy on markers of maternal inflammation.

        Financial Support: NIH grants R01 HD-060628, HD-065825 & MH-091351; European Commission FP7 289346 Project Early Nutrition

        Poster presented at the ICTS Translational Science Day at University of California Irvine on May 4, 2018

        • 1 supplemental PDF
        • Article
        • Peer Reviewed
        ICTS Publications (2018)

        Maternal inflammation during pregnancy is known to adversely impact fetal development, birth outcomes, and offspring physical and mental health. Diet and stress have been identified as important determinants of inflammation, yet their combined effects have not been examined in the context of pregnancy. The aim of this study was to examine the relationship between maternal diet with inflammatory potential and psychological stress, and to determine their interaction effect on concentrations of tumor necrosis factor (TNF)-α across pregnancy. We conducted a prospective longitudinal study of n = 202 women with three assessments during pregnancy, which included: ecological momentary assessment (EMA) of maternal stress using the perceived stress scale (PSS) short version; 24-h dietary recalls from which the dietary inflammatory index (DII) was computed; and serum measurements of TNF-α. Across pregnancy, higher perceived stress was associated with consumption of a more pro-inflammatory diet (r = 0.137; p < 0.05). In a linear regression model adjusted for covariates, DII was positively associated with TNF-α (B = 0.093, p = 0.010). The effect of the pro-inflammatory diet on concentrations of TNF-α was more pronounced in women reporting higher levels of stress (B = 0.134, p = 0.018 for DII*PSS interaction). These results highlight the need to consider nutrition and stress concurrently in the context of inflammation during pregnancy.

          Cover page: Maternal Stress Potentiates the Effect of an Inflammatory Diet in Pregnancy on Maternal Concentrations of Tumor Necrosis Factor Alpha.
          • Article
          • Peer Reviewed
          UC Irvine Previously Published Works (2018)
          Maternal inflammation during pregnancy is known to adversely impact fetal development, birth outcomes, and offspring physical and mental health. Diet and stress have been identified as important determinants of inflammation, yet their combined effects have not been examined in the context of pregnancy. The aim of this study was to examine the relationship between maternal diet with inflammatory potential and psychological stress, and to determine their interaction effect on concentrations of tumor necrosis factor (TNF)-α across pregnancy. We conducted a prospective longitudinal study of n = 202 women with three assessments during pregnancy, which included: ecological momentary assessment (EMA) of maternal stress using the perceived stress scale (PSS) short version; 24-h dietary recalls from which the dietary inflammatory index (DII) was computed; and serum measurements of TNF-α. Across pregnancy, higher perceived stress was associated with consumption of a more pro-inflammatory diet (r = 0.137; p < 0.05). In a linear regression model adjusted for covariates, DII was positively associated with TNF-α (B = 0.093, p = 0.010). The effect of the pro-inflammatory diet on concentrations of TNF-α was more pronounced in women reporting higher levels of stress (B = 0.134, p = 0.018 for DII*PSS interaction). These results highlight the need to consider nutrition and stress concurrently in the context of inflammation during pregnancy.
            Cover page: Maternal Stress Potentiates the Effect of an Inflammatory Diet in Pregnancy on Maternal Concentrations of Tumor Necrosis Factor Alpha.
            • Article
            • Peer Reviewed
            UC Irvine Previously Published Works (2019)
            Growing evidence supports an important role for the intrauterine environment in shaping fetal development and subsequent child health and disease risk. The fetal brain is particularly plastic, whereby even subtle changes in structure and function produced by in utero conditions can have long-term implications. Based on the consideration that conditions related to energy substrate and likelihood of survival to reproductive age are particularly salient drivers of fetal programming, maternal nutrition and stress represent the most commonly, but independently, studied factors in this context. However, the effects of maternal nutrition and stress are context dependent and may be moderated by one another. Studies examining the effects of the bidirectional nutrition-stress interplay in pregnancy on fetal programming of brain development are beginning to emerge in the literature. This review incorporates all currently available animal and human studies of this interplay and provides a synthesis and critical discussion of findings. Nine of the 10 studies included here assessed nutrition-stress interactions and offspring neurodevelopmental or brain development outcomes. Despite significant heterogeneity in study design and methodology, two broad patterns of results emerge to suggest that the effects of prenatal stress on various aspects of brain development may be mitigated by 1) higher fat diets or increased intake and/or status of specific dietary fats and 2) higher dietary intake or supplementation of targeted nutrients. The limitations of these studies are discussed, and recommendations are provided for future research to expand on this important area of fetal programming of brain development.
              Cover page: The Interplay Between Nutrition and Stress in Pregnancy: Implications for Fetal Programming of Brain Development
              • Article
              • Peer Reviewed
              UC Irvine Previously Published Works (2023)
              Prenatal depression is prevalent and adversely impacts maternal and infant health. This study addresses a critical literature gap and investigates the association between maternal diet quality and prenatal depressive symptoms, as well as the moderating effect of economic well-being on this link. A cross-sectional design was used, including 43 healthy pregnant women in the second trimester aggregated from two research projects. Prenatal depressive symptoms were assessed using the Edinburgh Postnatal Depression Scale. Dietary quality was evaluated using two non-consecutive 24 h dietary recalls, from which the Adapted Dietary Inflammatory Index (ADII) and the Healthy Eating Index (HEI)-2015 were derived. Economic well-being was indicated by the income-to-poverty ratio. A higher HEI-2015 (adherence to dietary guidelines; β = -0.53, p = 0.01) and negative ADII (anti-inflammatory diet; β = 0.40, p = 0.06) were associated with fewer prenatal depressive symp-toms. Among pregnant women with worse economic well-being, a pro-inflammatory diet was as-sociated with more prenatal depressive symptoms (b = 1.69, p = 0.004), but among those with better economic well-being, the association was not significant (b = 0.51, p = 0.09). Dietary interventions aimed at reducing dietary inflammation might hold some promise for improving mental health among pregnant women who are economically vulnerable.
                Cover page: Maternal Diet Quality and Prenatal Depressive Symptoms: The Moderating Role of Economic Well-Being
                • Article
                • Peer Reviewed
                UC Irvine Previously Published Works (2017)

                Background

                Several studies about humans and animals have separately examined the effects of prenatal nutrition and stress on fetal development, pregnancy, and birth outcomes, and subsequent child health and disease risk. Although substantial evidence from non-pregnant literature supports the presence of bidirectional interactions between nutrition and stress at various psychological, behavioral, and physiological levels, such interaction effects have not yet been systematically examined in the context of pregnancy.

                Summary

                This paper discusses the multifaceted and multilevel relationship between nutrition and stress. It then reviews the currently available observational and experimental evidence in animals and humans regarding the interplay between maternal psychosocial stress, dietary intake, and nutritional state during pregnancy, and implications for maternal and child health-related outcomes. Key Messages: During pregnancy, maternal psychosocial stress, dietary behavior, and nutritional state likely regulate and counter-regulate one another. Emerging evidence suggests that omega-3 fatty acids may attenuate maternal psychosocial stress, and that high maternal pre-pregnancy body mass index exacerbates unhealthy dietary behaviors under high-stress conditions. Longitudinal studies are warranted in order to understand the interplay between prenatal psychosocial stress, diet, and stress- and nutrition-related biomarkers to obtain further insight and inform the development and design of future, more effective intervention trials for improved maternal and child health outcomes.
                  Cover page: The Interplay between Maternal Nutrition and Stress during Pregnancy: Issues and Considerations.
                  • Article
                  • Peer Reviewed
                  UC Irvine Previously Published Works (2020)
                  Childhood obesity constitutes a major global public health challenge. A substantial body of evidence suggests that conditions and states experienced by the embryo/fetus in utero can result in structural and functional changes in cells, tissues, organ systems and homeostatic set points related to obesity. Furthermore, growing evidence suggests that maternal conditions and states experienced prior to conception, such as stress, obesity and metabolic dysfunction, may spill over into pregnancy and influence those key aspects of gestational biology that program offspring obesity risk. In this narrative review, we advance a novel hypothesis and life-span framework to propose that maternal exposure to childhood maltreatment may constitute an important and as-yet-underappreciated risk factor implicated in developmental programming of offspring obesity risk via the long-term psychological, biological and behavioral sequelae of childhood maltreatment exposure. In this context, our framework considers the key role of maternal-placental-fetal endocrine, immune and metabolic pathways and also other processes including epigenetics, oocyte mitochondrial biology, and the maternal and infant microbiomes. Finally, our paper discusses future research directions required to elucidate the nature and mechanisms of the intergenerational transmission of the effects of maternal childhood maltreatment on offspring obesity risk.
                    Cover page: Intergenerational transmission of the effects of maternal exposure to childhood maltreatment on offspring obesity risk: A fetal programming perspective
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