The composition of diet plays a vital role in maintaining health and may alter the human microbiota. The main focus to date has been on the association between diet and gut microbiota and only few studies have investigated the correlation between diet and the saliva microbiota. Our aim was to investigate whether eating habits and meal patterns are associated with the saliva microbiota. In this study, we included 842 adolescents aged 11–14 years from the Finnish Health in Teens (Fin-HIT) study cohort. Adolescents answered a web-based questionnaire, including information on eating habits, breakfast and dinner patterns at school. Questions related to diet were adapted to the age group. Previously three major eating habits were identified: healthy, unhealthy and fruit and vegetable avoiders. Saliva microbiota profiles were produced by 16S (V3-V4) sequencing on the Illumina HiSeq platform. We found that the regular breakfast eaters had a higher diversity than the irregular breakfast eaters (Shannon index mean 2.27 vs. 2.21, ANCOVA; p-value = 0.026 and inverse Simpsońs index mean 6.21 vs. 5.70, ANCOVA; p-value = 0.004 adjusted for gender, age, language, body mass index (BMI) categories, and sequencing depth). No associations were found between microbiota and eating habit groups, and between microbiota and dinner pattern groups. Microbial composition differed between the regular breakfast and irregular breakfast eaters (Bray-Curtis dissimilarity index, PERMANOVA; p = 0.021), but not between eating habit groups or dinner pattern groups. A high abundance of Prevotella was identified in the fruit and vegetable avoideŕs, irregular breakfast and irregular dinner eaters. Our results indicate that having an irregular breakfast may shape the saliva microbiota diversity. Prevotella may be an indicator of avoiding veggies and skipping meals.

Several dietary factors have been extensively investigated for associations with risk of breast cancer, but to date unequivocal evidence only exists for alcohol consumption. We sought to systematically evaluate the association between 92 dietary factors and breast cancer risk using a nutrient-wide association study approach. Using data from 272,098 women participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) study, we assessed dietary intake of 92 foods and nutrients estimated by dietary questionnaires. Cox regression with age as the time scale and adjustment for potential confounders, was used to quantify the association between each food or nutrient and risk of breast cancer. A false discovery rate (FDR) of 0.05 was used to select the set of foods and nutrients to evaluate in the independent replication cohort, the Netherlands Cohort Study (NLCS). During a median follow-up time of 15 years, 10,979 incident invasive breast cancers were identified in the women from the EPIC study. Six foods and nutrients were associated with risk of breast cancer when controlling the FDR at 0.05. Higher intake of alcohol overall was associated with a higher risk of breast cancer (hazard ratio (HR) for a 1 SD increment in intake = 1.05, 95% confidence interval (CI) 1.03–1.07), as was beer/cider intake and wine intake (HRs per 1 SD increment = 1.05, 95% CI 1.03–1.06 and 1.04, 95% CI 1.02–1.06, respectively), whereas higher intakes of fibre, apple/pear, and carbohydrates were associated with a lower risk of breast cancer (HRs per 1 SD increment = 0.96, 95% CI 0.94–0.98; 0.96, 95% CI 0.94–0.99; and 0.96, 95% CI 0.95–0.98, respectively). When evaluated in the NLCS (2368 invasive breast cancer cases), estimates for each of these foods and nutrients were similar in magnitude and direction, with the exception of beer/cider intake, which was not associated with risk of breast cancer in the NLCS. Our findings confirm the well-established increased risk of breast cancer associated with alcohol consumption, and suggest that higher intake of dietary fibre, and possibly fruit and carbohydrates, might be associated with reduced breast cancer risk.

In 2017, 11 million deaths related to non-communicable diseases (NCDs) were attributable to dietary risk factors (GBD, 2019). Helping consumers make healthier food choices hence appears as one key strategy to prevent NCDs-related mortality. To this end, political authorities are considering implementing a simple label to reflect the nutritional quality of food products. The five-colour Nutri-Score label, derived from the Nutrient Profiling System of the British Food Standards Agency (FSAm-NPS), has been chosen by several countries in Europe (France, Belgium, Spain). Yet, its implementation is still voluntary per EU labelling regulation. Scientific evidence is therefore needed regarding the relevance of the FSAm-NPS at the European level. Following on our results showing an increased risk of cancer related to the consumption of foods with a high FSAm-NPS score in the EPIC cohort, our objective is now to focus on NCDs-related mortality. Our prospective analyses included 501,594 adults from the EPIC cohort (1992–2015, median follow-up: 17.2 years). Mortality events occurring < 2 years after recruitment were excluded, leaving 50,743 death events (main causes: cancer, n = 21,971; cerebro/cardiovascular diseases, n = 12,407; respiratory diseases, n = 2,796). Usual food intakes were assessed with standardized country-specific diet assessment methods. The FSAm-NPS was calculated for each food/beverage using their 100-g content in energy, sugar, saturated fatty acid, sodium, fibres, proteins, and fruits/vegetables/legumes/nuts. The individual FSAm-NPS Dietary Index (DI) is obtained as an energy-weighted mean of the FSAm-NPS scores of all food items usually consumed by a participant. Cox proportional hazards models adjusted for confounding factors, including personal history of cancer, cardiovascular diseases and diabetes were computed. Fine and Gray models were also tested to take into account competing events for cause-specific mortality analyses. A higher FSAm-NPS DI score, reflecting a lower nutritional quality of the diet, was associated with a higher mortality risk overall (HRQ5vs.Q1 = 1.06 [95%CI: 1.02–1.09], P-trend < 0.001) and by cancer (HRQ5vs.Q1 = 1.06 [1.01–1.11], P-trend = 0.003) and respiratory diseases (HRQ5vs.Q1 = 1.33 [1.16–1.52], P-trend < 0.001), with similar results in competing events analyses. Associations with cerebro-/cardiovascular diseases mortality were weaker (HRQ5vs.Q1 = 1.05 [0.98,1.11], P-trend = 0.04) and no longer statistically significant in competing events analyses. In this large multinational European cohort, the consumption of food products with a higher FSAm-NPS score (lower nutritional quality of the foods consumed) was associated with a higher mortality risk, supporting the relevance of the FSAm-NPS to grade the nutritional quality of food products for public health applications (e.g, Nutri-Score) aiming to guide the consumers towards healthier food choices.

At present, analysis of diet and bladder cancer (BC) is mostly based on the intake of individual foods. The examination of food combinations provides a scope to deal with the complexity and unpredictability of the diet and aims to overcome the limitations of the study of nutrients and foods in isolation. This article aims to demonstrate the usability of supervised data mining methods to extract the food groups related to BC. In order to derive key food groups associated with BC risk, we applied the data mining technique C5.0 with 10-fold cross-validation in the BLadder cancer Epidemiology and Nutritional Determinants study, including data from eighteen case–control and one nested case–cohort study, compromising 8320 BC cases out of 31 551 participants. Dietary data, on the eleven main food groups of the Eurocode 2 Core classification codebook, and relevant non-diet data (i.e. sex, age and smoking status) were available. Primarily, five key food groups were extracted; in order of importance, beverages (non-milk); grains and grain products; vegetables and vegetable products; fats, oils and their products; meats and meat products were associated with BC risk. Since these food groups are corresponded with previously proposed BC-related dietary factors, data mining seems to be a promising technique in the field of nutritional epidemiology and deserves further examination.

Experimental studies have reported on the anti-inflammatory properties of polyphenols. However, results from epidemiological investigations have been inconsistent and especially studies using biomarkers for assessment of polyphenol intake have been scant. We aimed to characterise the association between plasma concentrations of thirty-five polyphenol compounds and low-grade systemic inflammation state as measured by high-sensitivity C-reactive protein (hsCRP). A cross-sectional data analysis was performed based on 315 participants in the European Prospective Investigation into Cancer and Nutrition cohort with available measurements of plasma polyphenols and hsCRP. In logistic regression analysis, the OR and 95 % CI of elevated serum hsCRP (>3 mg/l) were calculated within quartiles and per standard deviation higher level of plasma polyphenol concentrations. In a multivariable-adjusted model, the sum of plasma concentrations of all polyphenols measured (per standard deviation) was associated with 29 (95 % CI 50, 1) % lower odds of elevated hsCRP. In the class of flavonoids, daidzein was inversely associated with elevated hsCRP (OR 0·66, 95 % CI 0·46, 0·96). Among phenolic acids, statistically significant associations were observed for 3,5-dihydroxyphenylpropionic acid (OR 0·58, 95 % CI 0·39, 0·86), 3,4-dihydroxyphenylpropionic acid (OR 0·63, 95 % CI 0·46, 0·87), ferulic acid (OR 0·65, 95 % CI 0·44, 0·96) and caffeic acid (OR 0·69, 95 % CI 0·51, 0·93). The odds of elevated hsCRP were significantly reduced for hydroxytyrosol (OR 0·67, 95 % CI 0·48, 0·93). The present study showed that polyphenol biomarkers are associated with lower odds of elevated hsCRP. Whether diet rich in bioactive polyphenol compounds could be an effective strategy to prevent or modulate deleterious health effects of inflammation should be addressed by further well-powered longitudinal studies.

Improvements in colorectal cancer (CRC) detection and treatment have led to greater numbers of CRC survivors, for whom there is limited evidence on which to provide dietary guidelines to improve survival outcomes. Higher intake of red and processed meat and lower intake of fibre are associated with greater risk of developing CRC, but there is limited evidence regarding associations with survival after CRC diagnosis. Among 3789 CRC cases in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, pre-diagnostic consumption of red meat, processed meat, poultry and dietary fibre was examined in relation to CRC-specific mortality (n 1008) and all-cause mortality (n 1262) using multivariable Cox regression models, adjusted for CRC risk factors. Pre-diagnostic red meat, processed meat or fibre intakes (defined as quartiles and continuous grams per day) were not associated with CRC-specific or all-cause mortality among CRC survivors; however, a marginal trend across quartiles of processed meat in relation to CRC mortality was detected (P 0·053). Pre-diagnostic poultry intake was inversely associated with all-cause mortality among women (hazard ratio (HR)/20 g/d 0·92; 95 % CI 0·84, 1·00), but not among men (HR 1·00; 95 % CI 0·91, 1·09) (Pfor heterogeneity=0·10). Pre-diagnostic intake of red meat or fibre is not associated with CRC survival in the EPIC cohort. There is suggestive evidence of an association between poultry intake and all-cause mortality among female CRC survivors and between processed meat intake and CRC-specific mortality; however, further research using post-diagnostic dietary data is required to confirm this relationship.

Dietary patterns, which represent a broader picture of food and nutrient consumption, have gained increasing interest over the last decades. In a cohort design, we followed 27 544 women aged 29–49 years from baseline in 1991–1992. We collected data from an FFQ at baseline and body weight (BW) and waist circumference (WC) data both at baseline and at follow-up in 2003. We calculated the Mediterranean diet score (MDS, ranging from 0 to 9) and the Nordic diet score (NDS, ranging from 0 to 6). We used linear regression to examine the association between MDS and NDS (exposures) with subsequent BW change (ΔBW) and WC change (ΔWC) (outcomes) both continuously and categorically. Higher adherence to the MDS or NDS was not associated with ΔBW. The multivariable population average increment in BW was 0·03 kg (95 % CI −0·03, 0·09) per 1-point increase in MDS and 0·04 kg (95 % CI −0·02, 0·10) per 1-point increase in NDS. In addition, higher adherence to the MDS was not associated with ΔWC, with the multivariable population average increment per 1-point increase in MDS being 0·05 cm (95 % CI −0·03, 0·13). Higher adherence to the NDS was not significantly associated with gain in WC when adjusted for concurrent ΔBW. In conclusion, a higher adherence to the MDS or NDS was not associated with changes in average BW or WC in the present cohort followed for 12 years.

Whole-grain intake has been reported to be associated with a lower risk of several lifestyle-related diseases such as type 2 diabetes, CVD and some types of cancers. As measurement errors in self-reported whole-grain intake assessments can be substantial, dietary biomarkers are relevant to be used as complementary tools for dietary intake assessment. Alkylresorcinols (AR) are phenolic lipids found almost exclusively in whole-grain wheat and rye products among the commonly consumed foods and are considered as valid biomarkers of the intake of these products. In the present study, we analysed the plasma concentrations of five AR homologues in 2845 participants from ten European countries from a nested case–control study in the European Prospective Investigation into Cancer and Nutrition. High concentrations of plasma total AR were found in participants from Scandinavia and Central Europe and lower concentrations in those from the Mediterranean countries. The geometric mean plasma total AR concentrations were between 35 and 41 nmol/l in samples drawn from fasting participants in the Central European and Scandinavian countries and below 23 nmol/l in those of participants from the Mediterranean countries. The whole-grain source (wheat or rye) could be determined using the ratio of two of the homologues. The main source was wheat in Greece, Italy, the Netherlands and the UK, whereas rye was also consumed in considerable amounts in Germany, Denmark and Sweden. The present study demonstrates a considerable variation in the plasma concentrations of total AR and concentrations of AR homologues across ten European countries, reflecting both quantitative and qualitative differences in the intake of whole-grain wheat and rye.

Phenolic acids are secondary plant metabolites that may have protective effects against oxidative stress, inflammation and cancer in experimental studies. To date, limited data exist on the quantitative intake of phenolic acids. We estimated the intake of phenolic acids and their food sources and associated lifestyle factors in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Phenolic acid intakes were estimated for 36 037 subjects aged 35–74 years and recruited between 1992 and 2000 in ten European countries using a standardised 24 h recall software (EPIC-Soft), and their food sources were identified. Dietary data were linked to the Phenol-Explorer database, which contains data on forty-five aglycones of phenolic acids in 452 foods. The total phenolic acid intake was highest in Aarhus, Denmark (1265·5 and 980·7 mg/d in men and women, respectively), while the intake was lowest in Greece (213·2 and 158·6 mg/d in men and women, respectively). The hydroxycinnamic acid subclass was the main contributor to the total phenolic acid intake, accounting for 84·6–95·3 % of intake depending on the region. Hydroxybenzoic acids accounted for 4·6–14·4 %, hydroxyphenylacetic acids 0·1–0·8 % and hydroxyphenylpropanoic acids ≤ 0·1 % for all regions. An increasing south–north gradient of consumption was also found. Coffee was the main food source of phenolic acids and accounted for 55·3–80·7 % of the total phenolic acid intake, followed by fruits, vegetables and nuts. A high heterogeneity in phenolic acid intake was observed across the European countries in the EPIC cohort, which will allow further exploration of the associations with the risk of diseases.

The phyto-oestrogen enterolactone has been hypothesised to protect against hormone-dependent cancers, probably through its anti-oestrogenic potential. We investigated whether a higher level of plasma enterolactone was associated with a lower incidence of endometrial cancer in a case–cohort study in the ‘Diet, Cancer and Health’ cohort. The cohort study included 29 875 women aged 50–64 years enrolled between 1993 and 1997. Information on diet and lifestyle was provided by self-administrated questionnaires and blood was drawn from each participant. Time-resolved fluoroimmunoassay was used for biochemical determination of plasma enterolactone. A total of 173 cases and 149 randomly selected cohort members were included. We estimated incidence rate ratio (IRR) and 95 % CI by a Cox proportional hazards model. A 20 nmol/l higher plasma concentration of enterolactone was associated with a non-significant lower risk of endometrial cancer (IRR 0·93, 95 % CI 0·84, 1·04). When excluding women with low enterolactone concentrations (quartile 1) due to potential recent antibiotic use, the association became slightly stronger, but remained non-significant (IRR 0·90, 95 % CI 0·79, 1·02). Menopausal status, hormone replacement therapy or BMI did not modify the association. In conclusion, we found some support for a possible inverse association between plasma enterolactone concentration and endometrial cancer incidence.