UC Davis

Increasingly, the field of nutrition has come to recognize that a variety of factors influence an individual’s response to dietary intake and therefore, that a precision nutrition approach may be superior to broad population-level dietary recommendations in identifying an ideal dietary pattern to maintain optimal health and prevent disease. However, the ability to implement predictive precision nutrition approaches is constrained by limitations in the understanding of how different foods and dietary patterns affect various metabolic processes within an individual and between individuals. The research in this dissertation contributes to that understanding by describing the effects of dietary intake on factors that regulate metabolic responses and by interrogating between group differences in response. Chapter 1 contributes a systematic review of 22 studies in the published literature describing microRNA responses to both acute and long-term dietary interventions within human subjects. Chapter 2 used samples collected from a 16-week trial comparing supplementation with almonds to a calorie matched carbohydrate control to investigate the stability of fasting microRNA levels within pathways related to inflammation and cholesterol metabolism. Chapter 3 investigated glucose and insulin responses to grapes, grape juice, and a standard glucose beverage in the post-prandial period to investigate intra-individual differences in response and the sensitivity of microRNA response within inflammatory pathways following a diet challenge. Chapter 4 examined the relationship between nutritional phenotypes of post-prandial bile acids and fasting blood and insulin levels.