Homo sapiens may be more biologically adapted to the general diet that they would have eaten prior to the development of agriculture, the "Paleolithic diet". Yet few studies have examined this dietary pattern and any potential benefits it may have in reducing risk for modern chronic diseases.
In the first study, we investigated associations of two diet pattern scores, the Paleolithic and the Mediterranean, with circulating levels of two inflammation-related biomarkers, CRP and F2-isoprostanes, in a pooled cross-sectional study of an elective outpatient colonoscopy population (N=646). We found statistically significant trends for decreasing mean plasma biomarker concentrations with increasing quintiles of the Paleolithic and Mediterranean diet scores.
In the second study, we assessed associations of the two diet scores with prevalent incident, sporadic colorectal adenomas in a case-control study (n=2,301) of colorectal polyps. The adjusted odds ratios comparing those in the highest to the lowest quintiles of the diet scores were, respectively, 0.71 (95% confidence interval [CI]: 0.50, 1.02; Ptrend=0.02) and 0.74 (95% CI: 0.54, 1.03; Ptrend=0.05) when comparing the cases to the endoscopy-negative controls, and 0.84 (95% CI: 0.56, 1.26; Ptrend=0.14) and 0.77 (95% CI: 0.53, 1.11; Ptrend=0.13) when comparing the cases to the community controls.
In the third study, we investigated associations of the Paleolithic and the Mediterranean diet scores with all-cause and cause-specific mortality in a longitudinal cohort of adults (REGARDS; n=21,423). During a median follow-up of 6.25 years, 2,513 participants died. The adjusted hazard ratios comparing those in the highest to those in the lowest quintiles of the diet scores were, respectively, 0.77 (95% CI 0.67, 0.89; Ptrend<0.01) and 0.63 (95% CI 0.54, 0.73; Ptrend<0.01).
The results of these studies suggest that more Paleolithic- or Mediterranean-like diet patterns may be associated with lower levels of systemic inflammation and oxidative stress; lower risk for incident, sporadic colorectal adenomas; and lower risk of all-cause and cause-specific mortality. Overall, this dissertation contributes to our understanding of Paleolithic diet patterns by creating the first such diet pattern score and using it to assess the diet's association with risk of chronic disease.
Table of Contents
LIST OF FIGURES
LIST OF TABLES
Chapter 1: Introduction and Background.. 3
Nutrition, cardiovascular disease, cancer, and mortality. 4
Nutrition, obesity, and chronic disease. 5
Nutrition, inflammation, oxidative balance, and chronic disease. 6
Results from supplement trials 10
Dietary pattern scores 12
The Mediterranean diet 19
The Paleolithic diet 21
Conclusions/gaps in the literature. 28
Research Plan. 33
Objectives, Specific Aims, and Study Hypotheses 33
Significance and Impact of the Study. 41
Chapter 2: Associations of Paleolithic and Mediterranean diet pattern scores with biomarkers of inflammation and oxidative balance.. 43
Chapter 3: Paleolithic and Mediterranean Diet Pattern Scores and Risk for Incident, Sporadic Colorectal Adenomas. 63
Chapter 4: Associations of Paleolithic and Mediterranean Diet Patterns with All-Cause and Cause-Specific Mortality.. 81
Conclusions and Public Health Implications 100
Future Directions. 101
About this Dissertation
|Committee Chair / Thesis Advisor|
|Paleolithic Diet Scoring and Associations with Inflammation, Colorectal Adenomas, and Mortality ()||2018-08-28||