Viktoria Knaze

Differences in dietary intakes, food sources and determinants of total flavonoids between Mediterranean and non-Mediterranean countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) study

A greater adherence to the traditional Mediterranean (MED) diet is associated with a reduced risk of developing chronic diseases. This dietary pattern is based on higher consumption of plant products that are rich in flavonoids. We compared the total flavonoid dietary intakes, their food sources and various lifestyle factors between MED and non-MED countries participating in the EPIC study. Flavonoid intakes and their food sources for 35,628 subjects, aged 35-74 years and recruited between 1992 and 2000, in twenty-six study centres were estimated using standardised 24 h dietary recall software (EPIC-Soft®). An ad hoc food composition database on flavonoids was compiled using analytical data from the United States Department of Agriculture and Phenol-Explorer databases. Moreover, it was expanded to include using recipes, estimations of missing values and flavonoid retention factors. No significant differences in total flavonoid mean intake between non-MED countries (373·7 mg/d) and MED countries (370·2 mg/d) were observed. In the non-MED region, the main contributors were proanthocyanidins (48·2%) and flavan-3-ol monomers (24·9%) and the principal food sources were tea (25·7%) and fruits (32·8%). In the MED region, proanthocyanidins (59·0%) were by far the most abundant contributor and fruits (55·1%), wines (16·7%) and tea (6·8%) were the main food sources. The present study shows similar results for total dietary flavonoid intakes, but significant differences in flavonoid class intakes, food sources and some characteristics between MED and non-MED countries. These differences should be considered in studies about the relationships between flavonoid intake and chronic diseases.

Dietary intakes and food sources of phytoestrogens in the European Prospective Investigation into Cancer and Nutrition (EPIC) 24-hour dietary recall cohort

BACKGROUND/OBJECTIVES:Phytoestrogens are estradiol-like natural compounds found in plants that have been associated with protective effects against chronic diseases, including some cancers, cardiovascular diseases and osteoporosis. The purpose of this study was to estimate the dietary intake of phytoestrogens, identify their food sources and their association with lifestyle factors in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort.SUBJECTS/METHODS:Single 24-hour dietary recalls were collected from 36 037 individuals from 10 European countries, aged 35–74 years using a standardized computerized interview programe (EPIC-Soft). An ad hoc food composition database on phytoestrogens (isoflavones, lignans, coumestans, enterolignans and equol) was compiled using data from available databases, in order to obtain and describe phytoestrogen intakes and their food sources across 27 redefined EPIC centres.RESULTS:Mean total phytoestrogen intake was the highest in the UK health-conscious group (24.9 mg/day in men and 21.1 mg/day in women) whereas lowest in Greece (1.3 mg/day) in men and Spain-Granada (1.0 mg/day) in women. Northern European countries had higher intakes than southern countries. The main phytoestrogen contributors were isoflavones in both UK centres and lignans in the other EPIC cohorts. Age, body mass index, educational level, smoking status and physical activity were related to increased intakes of lignans, enterolignans and equol, but not to total phytoestrogen, isoflavone or coumestan intakes. In the UK cohorts, the major food sources of phytoestrogens were soy products. In the other EPIC cohorts the dietary sources were more distributed, among fruits, vegetables, soy products, cereal products, non-alcoholic and alcoholic beverages.CONCLUSIONS:There was a high variability in the dietary intake of total and phytoestrogen subclasses and their food sources across European regions.

Dietary flavonoid and lignan intake and gastric adenocarcinoma risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study

BACKGROUND Several experimental studies have suggested potential anticarcinogenic effects of flavonoids, although epidemiologic evidence for the impact of dietary flavonoids on risk of gastric cancer (GC) is limited. OBJECTIVE We investigated the association between intake of dietary flavonoids and lignans and incident GC. DESIGN The study followed 477,312 subjects (29.8% men) aged 35-70 y from 10 European countries who participated in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Validated dietary questionnaires and lifestyle information were collected at baseline. A food-composition database on flavonoids and lignans was compiled by using data from USDA and Phenol-Explorer databases. RESULTS During an average follow-up of 11 y, 683 incident GC cases (57.8% men) were mostly validated by a panel of pathologists and used in this analysis. We observed a significant inverse association between total flavonoid intake and GC risk in women (HR: 0.81; 95% CI: 0.70, 0.94; for the continuous variable after log₂ transformation) but not in men (HR: 0.97; 95% CI: 0.85, 1.09). In women, significant inverse associations with GC risk were also observed for intakes of some flavonoid subgroups (anthocyanidins, flavonols, flavones, and flavanols), particularly with intestinal type tumors for total flavonoid and flavanol intakes (P-heterogeneity < 0.1). After stratification by smoking status and sex, there was no significant heterogeneity in these associations between ever- and never-smokers. CONCLUSION Total dietary flavonoid intake is associated with a significant reduction in the risk of GC in women.

Dietary intakes and food sources of phenolic acids in the European Prospective Investigation into Cancer and Nutrition (EPIC) study

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.

Effects of food processing on polyphenol contents: A systematic analysis using Phenol-Explorer data

SCOPE The Phenol-Explorer web database (http://www.phenol-explorer.eu) was recently updated with new data on polyphenol retention due to food processing. Here, we analyze these data to investigate the effect of different variables on polyphenol content and make recommendations aimed at refining estimation of intake in epidemiological studies. METHODS AND RESULTS Data on the effects of processing upon 161 polyphenols compiled for the Phenol-Explorer database were analyzed to investigate the effects of polyphenol structure, food, and process upon polyphenol loss. These were expressed as retention factors (RFs), fold changes in polyphenol content due to processing. Domestic cooking of common plant foods caused considerable losses (median RF = 0.45-0.70), although variability was high. Food storage caused fewer losses, regardless of food or polyphenol (median RF = 0.88, 0.95, 0.92 for ambient, refrigerated, and frozen storage, respectively). The food under study was often a more important determinant of retention than the process applied. CONCLUSION Phenol-Explorer data enable polyphenol losses due to processing from many different foods to be rapidly compared. Where experimentally determined polyphenol contents of a processed food are not available, only published RFs matching at least the food and polyphenol of interest should be used when building food composition tables for epidemiological studies.

Flavonoid and lignan intake in relation to bladder cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study

Background:There is growing evidence of the protective role of dietary intake of flavonoids and lignans on cancer, but the association with bladder cancer has not been thoroughly investigated in epidemiological studies. We evaluated the association between dietary intakes of total and subclasses of flavonoids and lignans and risk of bladder cancer and its main morphological type, urothelial cell carcinoma (UCC), within the European Prospective Investigation into Cancer and Nutrition (EPIC) study.Methods:A cohort of 477 312 men and women mostly aged 35–70 years, were recruited in 10 European countries. At baseline, dietary flavonoid and lignan intakes were estimated using centre-specific validated questionnaires and a food composition database based on the Phenol-Explorer, the UK Food Standards Agency and the US Department of Agriculture databases.Results:During an average of 11 years of follow-up, 1575 new cases of primary bladder cancer were identified, of which 1425 were UCC (classified into aggressive (n=430) and non-aggressive (n=413) UCC). No association was found between total flavonoid intake and bladder cancer risk. Among flavonoid subclasses, significant inverse associations with bladder cancer risk were found for intakes of flavonol (hazard ratio comparing fifth with first quintile (HRQ5–Q1) 0.74, 95% confidence interval (CI): 0.61–0.91; P-trend=0.009) and lignans (HRQ5–Q1 0.78, 95% CI: 0.62–0.96; P-trend=0.046). Similar results were observed for overall UCC and aggressive UCC, but not for non-aggressive UCC.Conclusions:Our study suggests an inverse association between the dietary intakes of flavonols and lignans and risk of bladder cancer, particularly aggressive UCC.

Impact of thearubigins on the estimation of total dietary flavonoids in the European Prospective Investigation into Cancer and Nutrition (EPIC) study

Thearubigins (TR) are polymeric flavanol-derived compounds formed during the fermentation of tea leaves. Comprising ∼70% of total polyphenols in black tea, TR may contribute majorly to its beneficial effects on health. To date, there is no appropriate food composition data on TR, although several studies have used data from the US Department of Agriculture (USDA) database to estimate TR intakes. We aimed to estimate dietary TR in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort and assess the impact of including TR or not in the calculation of the total dietary flavonoid intake. Dietary data were collected using a single standardized 24-h dietary recall interviewer-administered to 36 037 subjects aged 35–74 years. TR intakes were calculated using the USDA database. TR intakes ranged from 0.9 mg/day in men from Navarra and San Sebastian in Spain to 532.5 mg/day in men from UK general population. TR contributed <5% to the total flavonoid intake in Greece, Spain and Italy, whereas in the UK general population, TR comprised 48% of the total flavonoids. High heterogeneity in TR intake across the EPIC countries was observed. This study shows that total flavonoid intake may be greatly influenced by TR, particularly in high black tea-consuming countries. Further research on identification and quantification of TR is needed to get more accurate dietary TR estimations.

Polyphenols: dietary assessment and role in the prevention of cancers

Purpose of review Polyphenols are a large and diverse family of phytochemicals widely consumed by humans. Here we summarize the latest epidemiological evidence for associations between cancer risk and polyphenol intake, taking into account difficulties in the accurate estimation of exposure. Recent findings Flavonoids are the most studied subgroup of polyphenols with regard to cancer risk. In recent epidemiological studies, total flavonoid intake has rarely been associated with a reduction in cancer risk. However, isoflavones, whose main dietary source is soy foods, plausibly reduce the risk of colorectal, breast, and prostate cancers, especially in Asian countries. Findings depend heavily upon the assessment of polyphenol intake, which is usually measured by food frequency questionnaires coupled to databases of food polyphenol composition. To a lesser extent, nutritional biomarkers have been used whenever estimating associations of polyphenol intake with cancer. Summary Polyphenol intake may mitigate cancer risk but this depends on cancer site, the subgroup of compounds under study, and accurate assessment of dietary exposure. Further work must better characterize the effects of intake of different flavonoid subclasses and begin to investigate the role of phenolic acids and other minor polyphenol classes.

Adapting the standardised computer- and interview-based 24 h dietary recall method (GloboDiet) for dietary monitoring in Latin America

OBJECTIVE The present study describes the procedure and approaches needed to adapt and harmonise the GloboDiet methodology, a computer- and interview-based 24 h dietary recall, for use in two Latin American pilot countries, Brazil and Mexico. DESIGN About seventy common and country-specific databases on foods, recipes, dietary supplements, quantification methods and coefficients were customised and translated following standardised guidelines, starting from existing Spanish and Portuguese versions. SETTING Brazil and Mexico. SUBJECTS Not applicable. RESULTS New subgroups were added into the existing common food classification together with new descriptors required to better classify and describe specific Brazilian and Mexican foods. Quantification methods were critically evaluated and adapted considering types and quantities of food consumed in these two countries, using data available from previous surveys. Furthermore, the photos to be used for quantification purposes were identified for compilation in country-specific but standardised picture booklets. CONCLUSIONS The completion of the customisation of the GloboDiet Latin America versions in these two pilot countries provides new insights into the adaptability of this dietary international tool to the Latin American context. The ultimate purpose is to enable dietary intake comparisons within and between Latin American countries, support building capacities and foster regional and international collaborations. The development of the GloboDiet methodology could represent a major benefit for Latin America in terms of standardised dietary methodologies for multiple surveillance, research and prevention purposes.

A Systematic Review of Peer-Reviewed Studies on Diet Quality Indexes Applied to Old Age: A Multitude of Predictors of Diet Quality

This review presents factors associated with diet quality in older adults and reveals possible reasons for some observed associations. It may facilitate a redevelopment of public health strategies. Formulating age-tailored dietary guidance that takes impaired health into account is one example that may lead to diet improvements in the elderly.