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Biomarkers of Phytochemical Intake in Human Trials Focusing on Modifiable Dietary Behaviors

Hill, Emily B
http://rave.ohiolink.edu/etdc/view?acc_num=osu1626797664722712

Abstract Details

2021, Doctor of Philosophy, Ohio State University, Health and Rehabilitation Sciences.
A plant-based dietary pattern is associated with improved health outcomes and is integrated within guidelines to promote public and individual health, such as the Dietary Guidelines for Americans (DGA) and the WCRF/AICR Cancer Prevention Guidelines. The number of cancer survivors has increased dramatically, and efforts are focusing upon promoting healthy survivorship free of cancer and enhancing longevity. Data suggests that diets of cancer survivors are inadequate in plant foods including fruits, vegetables, and whole grains. There is a critical need for studies focusing upon improving survivor dietary patterns. The development and validation of tools to assess the complex dietary intake of humans and biomarkers of exposure are crucial to this effort. Further, assessment of individual response to dietary intake remains complex and impacted by interacting components in the diet as well as genetic influences on digestion, absorption, and metabolism. Aligning dietary intake data with biomarkers of individual exposure and metabolism is critical for advancing knowledge. The goals of these studies were to explore select phytochemicals as biomarkers of dietary exposure within human trials by: (a) Defining changes in carotenoid status as an indicator of overall exposure to fruits and vegetables following an intervention with a healthy dietary pattern in free living cancer survivors; (b) Developing, evaluating, and validating a targeted LCMS flavonoid profile in 24-hour urine that is reflective of human intake and exposure to (poly)phenol-rich fruits and vegetables; and (c) Examining the relationships between a targeted (poly)phenol profile in the urine and/or dietary patterns and indicators of cardiometabolic health in a clinical trial of a healthy dietary pattern in cancer survivors. To achieve these goals, we conducted a clinical trial in cancer survivors (n=80) with overweight/obesity. Individuals enrolled in a lifestyle intervention with a primary goal of improving modifiable dietary behaviors to increase adherence to evidence-based dietary patterns (DGA and WCRF/AICR). Assessments were completed at enrollment, post-intervention (6 months), and post-maintenance (12 months) and included dietary intakes, anthropometrics, clinical outcomes, and plasma and 24-hour urine collection. We observed that plasma and skin carotenoids are strongly associated with improved dietary intakes of carotenoid-rich foods over weeks and months following intervention and improvements were maintained over time. Urinary (poly)phenol metabolites are a strong indicator of recent consumption, over multiple days, of foods rich in a diverse array of (poly)phenols. Together, data suggest that the multifaceted intervention led to greater intakes of plant-based foods and increases in diet quality, supported by concomitant increases in carotenoid and (poly)phenol exposure. We observed that implementation of a healthy dietary pattern and parallel improvements in biomarkers of carotenoid and (poly)phenol exposure are associated with successful weight loss, improved dietary indices, and other biomarkers of health. Patterns of blood and urinary metabolites of phytochemicals can provide a biomarker signature reflective of consumption patterns coupled with individual absorptive and metabolic capacity and may provide insight into how specific dietary changes may uniquely impact an individual and their health outcomes. In summary, these studies demonstrate the utility of an intense lifestyle intervention to improve dietary patterns and specific biomarkers of fruit and vegetable intake. The application of LCMS analysis of phytochemical profiles in blood and urine are useful tools predictive of intake of specific plant foods and provide insight into individual response. Such efforts will be useful in future randomized controlled clinical trials and metabolic epidemiologic studies to define relationships between foods and health.
Colleen Spees, PhD, MEd, RDN, LD, FAND (Advisor)
Steven Clinton, MD, PhD (Committee Member)
Fred Tabung, PhD, MSPH (Committee Member)
Xiaokui Mo, PhD, MAS (Committee Member)
Ken Riedl, PhD (Committee Member)
351 p.
Behavioral Sciences; Food Science; Health Sciences; Nutrition; Oncology
biomarkers; metabolomics; precision nutrition; phytochemicals; carotenoids; polyphenols; fruits and vegetables; dietary patterns; cancer survivors; lifestyle intervention; cardiometabolic health

Recommended Citations

Citations

  • Hill, E. B. (2021). Biomarkers of Phytochemical Intake in Human Trials Focusing on Modifiable Dietary Behaviors [Doctoral dissertation, Ohio State University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=osu1626797664722712

    APA Style (7th edition)

  • Hill, Emily. Biomarkers of Phytochemical Intake in Human Trials Focusing on Modifiable Dietary Behaviors. 2021. Ohio State University, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=osu1626797664722712.

    MLA Style (8th edition)

  • Hill, Emily. "Biomarkers of Phytochemical Intake in Human Trials Focusing on Modifiable Dietary Behaviors." Doctoral dissertation, Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1626797664722712

    Chicago Manual of Style (17th edition)

osu1626797664722712
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This open access ETD is published by The Ohio State University and OhioLINK.