BACKGROUND: Few studies have investigated the effect of dietary polyphenols on the complex human gut microbiota, and they focused mainly on single polyphenol molecules and select bacterial populations.
OBJECTIVE: The objective was to evaluate the effect of a moderate intake of red wine polyphenols on select gut microbial groups implicated in host health benefits.
DESIGN: Ten healthy male volunteers underwent a randomized, crossover, controlled intervention study. After a washout period, all of the subjects received red wine, the equivalent amount of de-alcoholized red wine, or gin for 20 d each. Total fecal DNA was submitted to polymerase chain reaction(PCR)-denaturing gradient gel electrophoresis and real-time quantitative PCR to monitor and quantify changes in fecal microbiota. Several biochemical markers were measured.
RESULTS: The dominant bacterial composition did not remain constant over the different intake periods. Compared with baseline, the daily consumption of red wine polyphenol for 4 wk significantly increased the number of Enterococcus, Prevotella, Bacteroides, Bifidobacterium, Bacteroides uniformis, Eggerthella lenta, and Blautia coccoides-Eubacterium rectale groups (P < 0.05). In parallel, systolic and diastolic blood pressures and triglyceride, total cholesterol, HDL cholesterol, and C-reactive protein concentrations decreased significantly (P < 0.05). Moreover, changes in cholesterol and C-reactive protein concentrations were linked to changes in the bifidobacteria number.
CONCLUSION: This study showed that red wine consumption can significantly modulate the growth of select gut microbiota in humans, which suggests possible prebiotic benefits associated with the inclusion of red wine polyphenols in the diet.
This trial was registered at controlled-trials.com as ISRCTN88720134
BACKGROUND: Alcohol consumption has multiple biochemical consequences. Only a few of these are useful as diagnostic markers, but many reflect potentially harmful or beneficial effects of alcohol. Average consumption of 2 to 4 drinks per day is associated with lower overall or cardiovascular mortality risk than either lower or higher intake. We have analyzed the dose-response relationships between reported alcohol consumption and 17 biomarkers, with emphasis on intake of up to 3 drinks per day. METHODS: Biochemical tests were performed on serum from 8,396 study participants (3,750 men and 4,646 women, aged 51 +/- 13 years, range 18 to 93) who had provided information on alcohol consumption in the week preceding blood collection. RESULTS: Gamma glutamyl transferase, alanine aminotransferase, aspartate aminotransferase, carbohydrate-deficient transferrin, urate, ferritin, and bilirubin showed little or no change with alcohol consumption below 2 to 3 drinks per day, but increased with higher intake. High-density lipoprotein cholesterol and albumin showed increasing results, and insulin showed decreasing results, across the entire range of alcohol use. Biphasic responses, where subjects reporting 1 to 2 drinks per day had lower results than those reporting either more or less alcohol use, occurred for triglycerides, glucose, C-reactive protein, alkaline phosphatase, and butyrylcholinesterase. Increasing alcohol use was associated with decreasing low-density lipoprotein cholesterol (LDL-C) in younger women, but higher LDL-C in older men. CONCLUSIONS: Some markers show threshold relationships with alcohol, others show continuous ones, and a third group show biphasic or U-shaped relationships. Overall, the biochemical sequelae of low-to-moderate alcohol use are consistent with the epidemiological evidence on morbidity and mortality.
BACKGROUND: Alcohol consumption is a potential trigger for inflammatory bowel disease (IBD) flare because of alcohol-induced oxidative stress and its deleterious effects on gut barrier function. Additionally, we have recently shown that alcohol consumption is associated with more symptoms in IBD. However, it is not known whether moderate daily alcohol consumption can modify IBD disease activity. To test what effects alcohol may have on patients with IBD, we evaluated the effect of moderate daily red wine for 1 week on two factors associated with recurrent IBD disease activity: intestinal permeability and stool calprotectin. METHODS: To assess the effects of moderate daily alcohol consumption on intestinal permeability and inflammation, we recruited 21 patients: 8 with inactive ulcerative colitis (UC), 6 with inactive Crohn's disease (CD), and 7 healthy controls. All participants with IBD completed a validated questionnaire on disease activity (Crohn's disease activity index or ulcerative colitis clinical activity index), to confirm they had inactive disease. All subjects then underwent a baseline assessment that included a blood draw, urine collection after sugar challenge, and stool collection. Subjects then consumed 1-3 glasses of red wine a day for 1 week (approx. 0.4 g EtOH/kg), and repeated the three measures. RESULTS: No subjects flared during the study. Moderate alcohol consumption did not significantly change either clinical disease activity scores or C-reactive protein. In contrast to healthy subjects, daily consumption of red wine significantly (1) decreased stool calprotectin in IBD subjects from baseline (p = 0.001) and (2) increased intestinal permeability as measured by urinary lactulose/mannitol excretion (marker of small bowel permeability) in CD (p = 0.028) or urinary sucralose secretion (marker of large bowel permeability) in UC (p = 0.012). CONCLUSIONS: One week of moderate consumption of red wine in inactive IBD was associated with a significant decrease in stool calprotectin and a significant increase in intestinal permeability. Our data suggests that patients with inactive IBD who drink red wine daily may be at an increased long-term risk for disease relapse.
AIMS: To assess the association of alcohol intake with high-sensitivity C-reactive protein (hs-CRP), uric acid and leukocyte count in blood, and whether sex and body mass index (BMI) modify these associations. METHODS: Individuals aged >/=18 years were randomly selected from the population of Porto, Portugal (70% of participation). A total of 840 women and 490 men with reliable information on inflammatory markers and alcohol intake, obtained from a validated food frequency questionnaire, were studied. Associations and their respective trends were estimated from generalized linear models, with adjustment for potential confounders. Analyses were stratified by sex and BMI. RESULTS: In women, adjusted hs-CRP levels (mg/l) were 2.69 in non-drinkers, 2.25 in drinkers of >0-15 g alcohol/day, 2.32 in drinkers of >15-30 g alcohol/day and 3.18 in drinkers of >30 g alcohol/day (P-value for the quadratic trend <0.001). In men, the association between alcohol intake and hs-CRP was positive and linear (P-value for the linear trend = 0.014). Alcohol intake was also positively and linearly associated with uric acid in each sex. Body weight modified these associations, which remained statistically significant only in normal-weight (BMI /=25 kg/m(2)) men for hs-CRP, and in normal-weight individuals for uric acid. No significant association between alcohol intake and leukocyte count was found. CONCLUSIONS: The association of alcohol intake with hs-CRP was J-shaped in women but positive and linear-shaped in men. Alcohol intake was directly associated with uric acid in men and women. BMI modifies the effect of alcohol on hs-CRP and uric acid levels in each sex.