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The gut microbiome is impacted by certain types of dietary fibre. However, the type, duration and dose needed to elicit gut microbial changes and whether these changes also influence microbial metabolites remain unclear. This study investigated the effects of supplementing healthy participants with two types of non-digestible carbohydrates (resistant starch (RS) and polydextrose (PD)) on the stool microbiota and microbial metabolite concentrations in plasma, stool and urine, as secondary outcomes in the Dietary Intervention Stem Cells and Colorectal Cancer (DISC) Study. The DISC study was a double-blind, randomised controlled trial that supplemented healthy participants with RS and/or PD or placebo for 50 d in a 2 × 2 factorial design. DNA was extracted from stool samples collected pre- and post-intervention, and V4 16S rRNA gene sequencing was used to profile the gut microbiota. Metabolite concentrations were measured in stool, plasma and urine by high-performance liquid chromatography. A total of fifty-eight participants with paired samples available were included. After 50 d, no effects of RS or PD were detected on composition of the gut microbiota diversity (alpha- and beta-diversity), on genus relative abundance or on metabolite concentrations. However, Drichlet's multinomial mixture clustering-based approach suggests that some participants changed microbial enterotype post-intervention. The gut microbiota and fecal, plasma and urinary microbial metabolites were stable in response to a 50-d fibre intervention in middle-aged adults. Larger and longer studies, including those which explore the effects of specific fibre sub-types, may be required to determine the relationships between fibre intake, the gut microbiome and host health. [ABSTRACT FROM AUTHOR]

Background: The World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) Cancer Prevention Recommendations are lifestyle-based guidelines which aim to reduce cancer risk. This study investigated, in the UK Biobank, associations between an abbreviated score to assess adherence to these Recommendations and the risk of all cancers combined and of 14 cancers for which there is strong evidence for links with diet, adiposity, and physical activity. Methods: We used data from 288,802 UK Biobank participants (mean age 56.2 years), cancer-free at baseline. An abbreviated version of the 2018 WCRF/AICR Score was calculated to assess adherence to five Recommendations on (i) body weight, (ii) physical activity, (iii) fruits, vegetables, and dietary fiber, (iv) red and processed meat, and (v) alcohol. Multivariable Cox proportional hazards models were used to analyze associations between the abbreviated score (range, 0-5 points) and cancer incidence, adjusting for confounders. Results: During a median follow-up of 8.2 years (interquartile range, 7.4-8.9), 23,448 participants were diagnosed with cancer. The abbreviated score was inversely associated with risk of cancer overall [HR: 0.93; 95% confidence interval (CI): 0.92-0.95 per 1-point increment], and breast (HR: 0.90; 95% CI: 0.87-0.94), colorectal (HR: 0.86; 95% CI: 0.83-0.90), lung (HR: 0.89; 95% CI: 0.84-0.94), kidney (HR: 0.83; 95% CI: 0.76-0.90), pancreatic (HR: 0.86; 95% CI: 0.79-0.94), uterine (HR: 0.79; 95% CI: 0.73-0.86), esophageal (HR: 0.82; 95% CI: 0.75-0.90), stomach (HR: 0.89; 95% CI: 0.79-0.99), and liver (HR: 0.80; 95% CI: 0.72-0.90) cancers. Conclusions: Greater adherence to the Cancer Prevention Recommendations, assessed using an abbreviated score, was associated with reduced risk of all cancers combined and of nine site-specific cancers. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) regulate several metabolic pathways and are potential biomarkers for early risk prediction of metabolic syndrome (MetS). Our aim was to evaluate the levels of 21 miRNAs in plasma according to MetS components and sex in adults. We employed a cross-sectional study of 192 adults aged 20 to 59 years old from the 2015 Health Survey of São Paulo with Focus in Nutrition. Data showed reduced levels of miR-16 and miR-363 in women with MetS; however, men with one or more risk factors showed higher levels of miR-let-7c and miR-30a. Individuals with raised waist circumference showed higher levels of miR-let-7c, miR-122, miR-30a, miR-146a, miR-15a, miR-30d and miR-222. Individuals with raised blood pressure had higher miR-30a, miR-122 and miR-30a levels. Plasma levels of four miRNAs (miR-16, miR-363, miR-375 and miR-486) were lower in individuals with low HDL-cholesterol concentrations. In addition, plasma levels of five miRNAs (miR-122, miR-139, miR-let-7c, miR-126 and miR-30a) were increased in individuals with high fasting plasma glucose and/or insulin resistance. Our results suggest that the pattern of miRNA levels in plasma may be a useful early biomarker of cardiometabolic components of MetS and highlight the sex differences in the plasma levels of miRNAs in individuals with MetS. [ABSTRACT FROM AUTHOR]

Bowel cancer risk is strongly influenced by lifestyle factors including diet and physical activity. Several studies have investigated the effects of adherence to the World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) cancer prevention recommendations on outcomes such as all-cause and cancer-specific mortality, but the relationships with molecular mechanisms that underlie the effects on bowel cancer risk are unknown. This study aimed to investigate the relationships between adherence to the WCRF/AICR cancer prevention recommendations and wingless/integrated (WNT)-pathway-related markers of bowel cancer risk, including the expression of WNT pathway genes and regulatory microRNA (miRNA), secreted frizzled-related protein 1 (SFRP1) methylation and colonic crypt proliferative state in colorectal mucosal biopsies. Dietary and lifestyle data from seventy-five healthy participants recruited as part of the DISC Study were used. A scoring system was devised including seven of the cancer prevention recommendations and smoking status. The effects of total adherence score and scores for individual recommendations on the measured outcomes were assessed using Spearman's rank correlation analysis and unpaired t tests, respectively. Total adherence score correlated negatively with expression of Myc proto-oncogene (c-MYC) (P =0·039) and WNT11 (P =0·025), and high adherers had significantly reduced expression of cyclin D1 (CCND1) (P =0·042), WNT11 (P =0·012) and c-MYC (P =0·048). Expression of axis inhibition protein 2 (AXIN2), glycogen synthase kinase (GSK3β), catenin β1 (CTNNB1) and WNT11 and of the oncogenic miRNA miR-17 and colonic crypt kinetics correlated significantly with scores for individual recommendations, including body fatness, red meat intake, plant food intake and smoking status. The findings from this study provide evidence for positive effects of adherence to the WCRF/AICR cancer prevention recommendations on WNT-pathway-related markers of bowel cancer risk. [ABSTRACT FROM AUTHOR]

Background: Few studies have explored the emerging adiposity marker A Body Shape Index (ABSI) with cancer risk. This study investigated the associations between ABSI and the incidence of cancer at 23 sites and all cancer combined., Methods: Data from 442,610 participants from the UK Biobank prospective study were included in this study. ABSI was used as the exposure. Incidence of cancer at 23 sites was the outcome. Cox proportional hazard models were performed to explore the association of ABSI, and combined ABSI and body mass index (BMI) with cancer risk, after adjusting for multiple testing., Results: 36,961 individuals developed cancer during the 8.8 years median follow-up. In multivariable analyses, participants in the highest tertile of ABSI had higher risk of lung [HR, 1.58; 95% confidence interval (CI), 1.44-1.74], liver (HR, 1.45; 95% CI, 1.18-1.77), esophagus (HR, 1.32; 95% CI, 1.12-1.57), colorectal (HR, 1.19; 95% CI, 1.10-1.28), and breast (HR, 1.05; 95% CI, 1.04-1.17) cancers, and all cancers combined (HR, 1.11; 95% CI, 1.08-1.14) compared with the lowest tertile. These associations remained significant after adjustment for BMI. When ABSI was combined with BMI, participants in the highest ABSI who also had a BMI ≥ 25 kg/m 2 were at higher risk of uterus, esophagus, liver, stomach, colorectal, and breast cancers, as well as all cancers combined, compared with those in the lowest ABSI tertile with a normal BMI., Conclusions: ABSI is associated with an increased risk of five cancers as well as all cancers combined, independently of BMI., Impact: ABSI is a useful marker for adiposity. However, cancer risk prediction improves with the combination of BMI., (©2021 American Association for Cancer Research.)