A large body of evidence has linked unhealthy eating patterns with an alarming increase in obesity and chronic disease worldwide. However, existing methods of assessing dietary intake in nutritional epidemiology rely on food frequency questionnaires or dietary records that are prone to bias and selective reporting. Herein, metabolic phenotyping was performed on 42 healthy participants from the Diet and Gene Intervention (DIGEST) pilot study, a parallel two-arm randomized clinical trial that provided complete diets to all participants. Matching urine and plasma specimens were collected at baseline and following 2 weeks of provision of either a Prudent or Western diet with a weight-maintaining menu plan designed by a dietician. Targeted and nontargeted metabolite profiling was conducted using three complementary analytical platforms, where 80 plasma metabolites and 84 creatinine-normalized urinary metabolites were reliably measured (CV < 30%) in the majority of participants (> 75%) after implementing a rigorous data workflow for metabolite authentication with stringent quality control. We classified a panel of metabolites with distinctive trajectories following 2 weeks of food provisions when using complementary univariate and multivariate statistical models. Unknown metabolites associated with contrasting dietary patterns were identified with high resolution MS/MS and/or co-elution after spiking with authentic standards. Overall, 3-methylhistidine and proline betaine concentrations increased consistently after participants were assigned a Prudent diet (q< 0.05) in both plasma and urine samples with a corresponding decrease in the Western diet group. Similarly, creatinine-normalized urinary imidazole propionate, hydroxypipecolic acid, dihydroxybenzoic acid, and enterolactone glucuronide, as well as plasma ketoleucine and ketovaline increased with a Prudent diet (p< 0.05) after adjustments for age, sex and BMI. In contrast, plasma myristic acid, linoelaidic acid, linoleic acid, a-linoleic acid, pentadecanoic acid, alanine, proline, carnitine and deoxycarnitine, as well as urinary acesulfame K increased among participants following a Western diet. Most metabolites were also correlated (r > ±0.30, p< 0.05) to changes in average intake of specific nutrients from self-reported diet records reflecting good adherence to assigned food provisions. Our study revealed robust biomarkers sensitive to short-term changes in habitual diet for accurate monitoring of healthy eating patterns in free-living populations, which is required for validating evidence-based public health policies for chronic disease prevention.

Specific foods and nutrients help prevent the progression from persistent high-risk human papillomavirus (hrHPV) infection to cervical cancer (CC). We aimed to focus on dietary patterns which may be associated with hrHPV status and risk of high-grade cervical intraepithelial neoplasia (CIN2+). Overall, 539 eligible women, including 127 CIN2+, were enrolled in a cross-sectional study, and tested for hrHPV infection. Food intakes were estimated using a food frequency questionnaire. Logistic regression models were applied. Using the Mediterranean Diet Score, we demonstrated that, among 252 women with normal cervical epithelium, medium adherence to Mediterranean diet decreased odds of hrHPV infection when compared to low adherence (adjOR=0.40, 95%CI=0.22-0.73). Using principle component analysis, we also identified two dietary patterns which explained 14.31% of variance. Women in the 3^rd and 4^th quartiles of the “western pattern” had higher odds of hrHPV infection when compared with 1^st quartile (adjOR=1.77, 95%CI=1.04-3.54 and adjOR=1.97, 95%CI=1.14-4.18, respectively). Adjusting for hrHPV status and age, women in the 3^rd quartile of the “prudent pattern” had lower odds of CIN2+ when compared with 1^st quartile (OR=0.50, 95%CI=0.26-0.98). Our study is the first to demonstrate the association of dietary patterns with hrHPV infection and CC, discouraging unhealthy habits in favour of Mediterranean-like diet.