Shifting towards optimized healthy and sustainable Dutch diets: impact on protein quality.

PURPOSE: To reduce the environmental impact of Western diets, a reduction of meat consumption and a substitution by plant-based protein sources is needed. This protein transition will affect the quantity and quality of dietary protein. Therefore, the aim of this study was to evaluate the protein adequacy of diets optimized for nutritional health and diet-related greenhouse gas emission (GHGE). METHODS: Data from 2150 adult participants of the Dutch National Food Consumption Survey were used, with diet assessed using two non-consecutive 24 h dietary recalls. Utilizable protein of current diets per day was based on meal composition and the Protein Digestibility-Corrected Amino Acid Score and was compared to protein requirements. Optimized diets were derived as linear combinations of current diets that minimized GHGE and maximized the Dutch Healthy Diet 2015 score, with/without constraints to keep dietary change within 33% of current consumption. Protein adequacy was evaluated in both current and optimized diets. RESULTS: In all age and gender strata, the healthiest diets had higher GHGE, the most sustainable diets had the lowest dietary quality, though higher than current diets, and protein adequacy remained sufficient. When limiting dietary change to 33% of current consumption, in the most promising trade-off diet GHGE was reduced by 12-16%. The current diet provided 1.4-2.2 times the required amount of utilizable protein. CONCLUSION: These results suggest that a realistic aim for the next decade might be to reduce diet-related GHGE to 12-16% of the current levels without compromising protein adequacy and diet quality. To achieve global targets, upstream food system transformations are needed with subsequent dietary changes.

Exploring culturally acceptable, nutritious, affordable and low climatic impact diet for Japanese diets: proof of concept of applying a new modelling approach using data envelopment analysis.

A future sustainable dietary pattern for Japanese is yet undefined. This study aimed to explore more sustainable Japanese diets that are nutritious, affordable and with low greenhouse gas emissions (GHGE) and particular emphasis on cultural acceptability. A newly developed data envelopment analysis (DEA) diet model was applied to 4-d dietary record data among 184 healthy Japanese men and 185 women volunteers aged 21-69 years. Alternative diets were calculated as the linear combinations of observed diets. Firstly, for each individual, four modelled diets were calculated that maximised cultural acceptability (i.e. minimise dietary change from observed diet), maximised nutritional quality assessed by the Nutrient-Rich Food Index (NRF), minimised monetary diet costs or minimised diet-related GHGE. The final modelled diet combined all four indicators. In the first four models, the largest improvement was obtained for each targeted indicator separately, while relatively small improvements or unwanted changes were observed for other indicator. When all indicators were aimed to optimise, the NRF score and diet-related GHGE were improved by 8-13 % with the lower monetary cost than observed diets, although the percentage improvement was a bit smaller than the separate models. The final modelled diets demanded increased intakes for whole grains, fruits, milk/cream/yogurt, legumes/nuts, and decreased intakes for red and processed meat, sugar/confectioneries, alcoholic and sweetened beverages, and seasonings in both sexes. In conclusion, more sustainable dietary patterns considering several indicators are possible for Japanese, while total improvement is moderate due to trade-offs between indicators and methodological limitation of DEA diet model.

Evaluation of foods, drinks and diets in the Netherlands according to the degree of processing for nutritional quality, environmental impact and food costs.

OBJECTIVE: This study investigates nutritional quality, environmental impact and costs of foods and drinks and their consumption in daily diets according to the degree of processing across the Dutch population. DESIGN: The NOVA classification was used to classify the degree of processing (ultra-processed foods (UPF) and ultra-processed drinks (UPD)). Food consumption data were derived from the Dutch National Food Consumption Survey 2012-2016. Indicators assessed were nutritional quality (saturated fatty acids (SFA), sodium, mono and disaccharides (sugar), fibre and protein), environmental impact (greenhouse gas (GHG) emissions and blue water use) and food costs. SETTING: The Netherlands. PARTICIPANTS: Four thousand three hundred thirteen Dutch participants aged 1 to 79 years. RESULTS: Per 100 g, UPF were more energy-dense and less healthy than unprocessed or minimally processed foods (MPF); UPF were associated with higher GHG emissions and lower blue water use, and were cheaper. The energy and sugar content of UPD were similar to those of unprocessed or minimally processed drinks (MPD); associated with similar GHG emissions but blue water use was less, and they were also more expensive. In the average Dutch diet, per 2000 kcal, ultra-processed foods and drinks (UPFD) covered 29% (456 g UPF and 437 g UPD) of daily consumption and 61% of energy intake. UPFD consumption was higher among children than adults, especially for UPD. UPFD consumption determined 45% of GHG emissions, 23% of blue water use and 39% of expenses for daily food consumption. UPFD consumption contributed 54% to 72% to daily sodium, sugar and SFA intake. CONCLUSIONS: Compared with unprocessed or minimally processed foods and drinks, UPF and UPD were found to be less healthy considering their high energy, SFA, sugar and sodium content. However, UPF were associated higher GHG emissions and with less blue water use and food costs. Therefore daily blue water use and food costs might increase if UPF are replaced by those unprocessed or minimally processed. As nutritional quality, environmental impacts and food costs relate differently to the NOVA classification, the classification is not directly applicable to identify win-win-wins of nutritional quality, environmental impact and costs of diets.

Improving health and carbon footprints of European diets using a benchmarking approach.

OBJECTIVE: This study aimed to identify diets with improved nutrient quality and environmental impact within the boundaries of dietary practices. DESIGN: We used Data Envelopment Analysis to benchmark diets for improved adherence to food-based dietary guidelines (FBDG). We then optimised these diets for dietary preferences, nutrient quality and environmental impact. Diets were evaluated using the Nutrient Rich Diet score (NRD15.3), diet-related greenhouse gas emission (GHGE) and a diet similarity index that quantified the proportion of food intake that remained similar as compared with the observed diet. SETTING: National dietary surveys of four European countries (Denmark, Czech Republic, Italy and France). SUBJECTS: Approximately 6500 adults, aged 18-64 years. RESULTS: When dietary preferences were prioritised, NRD15·3 was ~6 % higher, GHGE was ~4 % lower and ~85 % of food intake remained similar. This diet had higher amounts of fruit, vegetables and whole grains than the observed diet. When nutrient quality was prioritised, NRD15·3 was ~16 % higher, GHGE was ~3 % lower and ~72 % of food intake remained similar. This diet had higher amounts of legumes and fish and lower amounts of sweetened and alcoholic beverages. Finally, when environmental impact was prioritised, NRD15·3 was ~9 % higher, GHGE was ~21 % lower and ~73 % of food intake remained similar. In this diet, red and processed meat partly shifted to either eggs, poultry, fish or dairy. CONCLUSIONS: Benchmark modelling can generate diets with improved adherence to FBDG within the boundaries of dietary practices, but fully maximising health and minimising GHGE cannot be achieved simultaneously.

Is nutrition science ready for the twenty-first century? Moving towards transdisciplinary impacts in a changing world.

Malnutrition in an obese world was the fitting title of the 13th Federation of European Nutrition Societies (FENS) conference held in October 2019. Many individuals do not eat a healthy, well-balanced diet, and this is now understood to be a major driver of increased disease risk and illness. Moreover, both our current eating patterns and the food system as a whole are environmentally unsustainable, threatening the planetary systems we depend on for survival. As we attempt to feed a growing global population, food systems will increasingly be confronted with their environmental impacts, with the added challenge of climate change-induced threats to food production. As we move into the third decade of the twenty-first century, these challenges demand that the nutrition research community reconsider its scope, concepts, methods, and societal role. At a pre-meeting workshop held at the FENS conference, over 70 researchers active in the field explored ways to advance the discipline's capacity to address cross-cutting issues of personal, public and planetary health. Using the world cafe method, four themed discussion tables explored (a) the breadth of scientific domains needed to meet the current challenges, (b) the nature and definition of the shifting concepts in nutrition sciences, (c) the next-generation methods required and (d) communication and organisational challenges and opportunities. As a follow-up to earlier work [1], here we report the highlights of the discussions, and propose the next steps to advance responsible research and innovation in the domain of nutritional science.

Designing healthier and acceptable diets using data envelopment analysis.

OBJECTIVE: The objective of this research is to propose methodology that can be used to benchmark current diets based on their nutrient intakes and to provide guidelines for improving less healthy diets in a way that is acceptable for the studied population. DESIGN: We discuss important limitations of current diet models that use optimisation techniques to design healthier and acceptable diets. We illustrate how data envelopment analysis could be used to overcome such limitations, and we describe mathematical models that can be used to calculate not only healthier but also acceptable diets. SETTING: We used data from the Nutrition Questionnaires plus dataset of habitual diets of a general population of adult men and women in The Netherlands (n 1735). PARTICIPANTS: Adult population. RESULTS: We calculated healthier diets with substantial higher intakes of protein, fibre, Fe, Ca, K, Mg and vitamins, and substantially lower intakes of Na, saturated fats and added sugars. The calculated diets are combinations of current diets of individuals that belong to the same age/gender group and comprise of food item intakes in proportions observed in the sample. CONCLUSIONS: The proposed methodology enables the benchmarking of existing diets and provides a framework for proposing healthier alternative diets that resemble the current diet in terms of foods intake as much as possible.

Geographic and socioeconomic diversity of food and nutrient intakes: a comparison of four European countries.

PURPOSE: Public health policies and actions increasingly acknowledge the climate burden of food consumption. The aim of this study is to describe dietary intakes across four European countries, as baseline for further research towards healthier and environmentally-friendlier diets for Europe. METHODS: Individual-level dietary intake data in adults were obtained from nationally-representative surveys from Denmark and France using a 7-day diet record, Italy using a 3-day diet record, and Czech Republic using two replicates of a 24-h recall. Energy-standardised food and nutrient intakes were calculated for each subject from the mean of two randomly selected days. RESULTS: There was clear geographical variability, with a between-country range for mean fruit intake from 118 to 199 g/day, for vegetables from 95 to 239 g/day, for fish from 12 to 45 g/day, for dairy from 129 to 302 g/day, for sweet beverages from 48 to 224 ml/day, and for alcohol from 8 to 15 g/day, with higher intakes in Italy for fruit, vegetables and fish, and in Denmark for dairy, sweet beverages and alcohol. In all countries, intakes were low for legumes (< 20 g/day), and nuts and seeds (< 5 g/day), but high for red and processed meat (> 80 g/day). Within countries, food intakes also varied by socio-economic factors such as age, gender, and educational level, but less pronounced by anthropometric factors such as overweight status. For nutrients, intakes were low for dietary fibre (15.8-19.4 g/day) and vitamin D (2.4-3.0 µg/day) in all countries, for potassium (2288-2938 mg/day) and magnesium (268-285 mg/day) except in Denmark, for vitamin E in Denmark (6.7 mg/day), and for folate in Czech Republic (212 µg/day). CONCLUSIONS: There is considerable variation in food and nutrient intakes across Europe, not only between, but also within countries. Individual-level dietary data provide insight into the heterogeneity of dietary habits beyond per capita food supply data, and this is crucial to balancing healthy and environmentally-friendly diets for European citizens.

FFQ versus repeated 24-h recalls for estimating diet-related environmental impact.

BACKGROUND: There is an increasing interest in estimating environmental impact of individuals' diets by using individual-level food consumption data. However, like assessment of nutrient intakes, these data are prone to substantial measurement errors dependent on the method of dietary assessment, and this often result in attenuation of associations. PURPOSE: To investigate the performance of a food frequency questionnaire (FFQ) for estimating the environmental impact of the diet as compared to independent 24-h recalls (24hR), and to study the association between environmental impact and dietary quality for the FFQ and 24hR. METHODS: We analysed cross-sectional data from 1169 men and women, aged 20-76 years, who participated in the NQplus study, the Netherlands. They completed a 216-item FFQ and two replicates of web-based 24hR. Life cycle assessments of 207 food products were used to calculate greenhouse gas emissions, fossil energy and land use, summarised into an aggregated score, pReCiPe. Validity of the FFQ was evaluated against 24hRs using correlation coefficients and attenuation coefficients. Associations with dietary quality were based on Dutch Healthy Diet 15-index (DHD15-index) and Nutrient Rich Diet score (NRD9.3). RESULTS: For pReCiPe, correlation coefficient between FFQ and 24hR was 0.33 when adjusted for covariates age, gender and BMI, and increased to 0.76 when de-attenuated for within-subject variation in the 24hR. Energy-adjustment slightly reduced these correlations (r = 0.71 for residuals of observed values and 0.59 for residuals of density values). Covariate-adjusted attenuation coefficient for the FFQ was 0.56 (ʎ1 = 0.56 and ʎ1 = 0.65 for observed and density residuals), slightly lower than without covariate adjustment. Diet-related environmental impact was inversely associated with the food-based DHD15-index for both FFQ and 24hR, while associations with the nutrient-based NRD9.3 were inconsistent. CONCLUSIONS: The FFQ slightly underestimated environmental impact when compared to 24hR. Associations with dietary quality are highly dependent on the diet score used, and less dependent on the method of dietary assessment.

User-documented food consumption data from publicly available apps: an analysis of opportunities and challenges for nutrition research.

BACKGROUND: The need for a better understanding of food consumption behaviour within its behavioural context has sparked the interest of nutrition researchers for user-documented food consumption data collected outside the research context using publicly available nutrition apps. The study aims to characterize the scientific, technical, legal and ethical features of this data in order to identify the opportunities and challenges associated with using this data for nutrition research. METHOD: A search for apps collecting food consumption data was conducted in October 2016 against UK Google Play and iTunes storefronts. 176 apps were selected based on user ratings and English language support. Publicly available information from the app stores and app-related websites was investigated and relevant data extracted and summarized. Our focus was on characteristics related to scientific relevance, data management and legal and ethical governance of user-documented food consumption data. RESULTS: Food diaries are the most common form of data collection, allowing for multiple inputs including generic food items, packaged products, or images. Standards and procedures for compiling food databases used for estimating energy and nutrient intakes remain largely undisclosed. Food consumption data is interlinked with various types of contextual data related to behavioural motivation, physical activity, health, and fitness. While exchange of data between apps is common practise, the majority of apps lack technical documentation regarding data export. There is a similar lack of documentation regarding the implemented terms of use and privacy policies. While users are usually the owners of their data, vendors are granted irrevocable and royalty free licenses to commercially exploit the data. CONCLUSION: Due to its magnitude, diversity, and interconnectedness, user-documented food consumption data offers promising opportunities for a better understanding of habitual food consumption behaviour and its determinants. Non-standardized or non-documented food data compilation procedures, data exchange protocols and formats, terms of use and privacy statements, however, limit possibilities to integrate, process and share user-documented food consumption data. An ongoing research effort is required, to keep pace with the technical advancements of food consumption apps, their evolving data networks and the legal and ethical regulations related to protecting app users and their personal data.

Validating fatty acid intake as estimated by an FFQ: how does the 24 h recall perform as reference method compared with the duplicate portion?

OBJECTIVE: To compare the performance of the commonly used 24 h recall (24hR) with the more distinct duplicate portion (DP) as reference method for validation of fatty acid intake estimated with an FFQ. DESIGN: Intakes of SFA, MUFA, n-3 fatty acids and linoleic acid (LA) were estimated by chemical analysis of two DP and by on average five 24hR and two FFQ. Plasma n-3 fatty acids and LA were used to objectively compare ranking of individuals based on DP and 24hR. Multivariate measurement error models were used to estimate validity coefficients and attenuation factors for the FFQ with the DP and 24hR as reference methods. SETTING: Wageningen, the Netherlands. SUBJECTS: Ninety-two men and 106 women (aged 20-70 years). RESULTS: Validity coefficients for the fatty acid estimates by the FFQ tended to be lower when using the DP as reference method compared with the 24hR. Attenuation factors for the FFQ tended to be slightly higher based on the DP than those based on the 24hR as reference method. Furthermore, when using plasma fatty acids as reference, the DP showed comparable to slightly better ranking of participants according to their intake of n-3 fatty acids (0·33) and n-3:LA (0·34) than the 24hR (0·22 and 0·24, respectively). CONCLUSIONS: The 24hR gives only slightly different results compared with the distinctive but less feasible DP, therefore use of the 24hR seems appropriate as the reference method for FFQ validation of fatty acid intake.

Systematic Review of Observational Studies with Dose-Response Meta-Analysis between Folate Intake and Status Biomarkers in Adults and the Elderly.

BACKGROUND: Dietary reference values for folate intake vary widely across Europe. METHODS: MEDLINE and Embase through November 2016 were searched for data on the association between folate intake and biomarkers (serum/plasma folate, red blood cell [RBC] folate, plasma homocysteine) from observational studies in healthy adults and elderly. The regression coefficient of biomarkers on intake (ß) was extracted from each study, and the overall and stratified pooled ß and SE (ß) were obtained by random effects meta-analysis on a double log scale. These dose-response estimates may be used to derive folate intake reference values. RESULTS: For every doubling in folate intake, the changes in serum/plasma folate, RBC folate and plasma homocysteine were +22, +21, and -16% respectively. The overall pooled regression coefficients were ß = 0.29 (95% CI 0.21-0.37) for serum/plasma folate (26 estimates from 17 studies), ß = 0.28 (95% CI 0.21-0.36) for RBC (13 estimates from 11 studies), and ß = -0.21 (95% CI -0.31 to -0.11) for plasma homocysteine (10 estimates from 6 studies). CONCLUSION: These estimates along with those from randomized controlled trials can be used for underpinning dietary recommendations for folate in adults and elderly.

Capable and credible? Challenging nutrition science.

Nutrition science has enriched our understanding of how to stay healthy by producing valuable knowledge about the interaction of nutrients, food, and the human body. Nutrition science also has raised societal awareness about the links between food consumption and well-being, and provided the basis for food regulations and dietary guidelines. Its collaborative and interdisciplinary research has accomplished much, scientifically and socially. Despite this, nutrition science appears to be in crisis and is currently confronted with a public reluctance to trust nutritional insights. Though deflating trust is a general phenomenon surrounding the scientific community, its impact on nutrition science is particularly strong because of the crucial role of nutrition in everyone's daily life. We, a Dutch collective of nutritionists, medical doctors, philosophers and sociologists of science ( http://www.nutritionintransition.nl ), have diagnosed that nutrition science is meeting inherent boundaries. This hampers conceptual and methodological progress and the translation of novel insights into societal benefit and trust. In other words, nutrition science is facing limitations to its capability and credibility, impeding its societal value. We take up the challenge to halt the threatening erosion of nutrition science's capability and credibility, and explore a way forward. We analyse limitations to capability and credibility, then argue that nutrition science is caught in a vicious circle, and end by offering some suggestions to transcend the limitations and escape the current deadlock. We invite nutritional experts as well as scholars from adjacent disciplines to engage in the discussion.

Operationalising the health aspects of sustainable diets: a review.

OBJECTIVE: Shifting towards a more sustainable food consumption pattern is an important strategy to mitigate climate change. In the past decade, various studies have optimised environmentally sustainable diets using different methodological approaches. The aim of the present review was to categorise and summarise the different approaches to operationalise the health aspects of environmentally sustainable diets. DESIGN: Conventional keyword and reference searches were conducted in PubMed, Scopus, Web of Knowledge and CAB Abstracts. Inclusion criteria were: (i) English-language publication; (ii) published between 2005 and October 2015; (iii) dietary data collected for the diet as a whole at the national, household or individual level; (iv) comparison of the current diet with dietary scenarios; and (v) for results to consider the health aspect in some way. SETTING: Consumer diets. SUBJECTS: Adult population. RESULTS: We reviewed forty-nine studies that combined the health and environmental aspects of consumer diets. Hereby, five approaches to operationalise the health aspect of the diet were identified: (i) food item replacements; (ii) dietary guidelines; (iii) dietary quality scores; (iv) diet modelling techniques; and (v) diet-related health impact analysis. CONCLUSIONS: Although the sustainability concept is increasingly popular and widely advocated by nutritional and environmental scientists, the journey towards designing sustainable diets for consumers has only just begun. In the context of operationalising the health aspects, diet modelling might be considered the preferred approach since it captures the complexity of the diet as a whole. For the future, we propose SHARP diets: environmentally Sustainable (S), Healthy (H), Affordable (A), Reliable (R) and Preferred from the consumer's perspective (P).

BMI was found to be a consistent determinant related to misreporting of energy, protein and potassium intake using self-report and duplicate portion methods.

OBJECTIVE: As misreporting, mostly under-reporting, of dietary intake is a generally known problem in nutritional research, we aimed to analyse the association between selected determinants and the extent of misreporting by the duplicate portion method (DP), 24 h recall (24hR) and FFQ by linear regression analysis using the biomarker values as unbiased estimates. DESIGN: For each individual, two DP, two 24hR, two FFQ and two 24 h urinary biomarkers were collected within 1·5 years. Also, for sixty-nine individuals one or two doubly labelled water measurements were obtained. The associations of basic determinants (BMI, gender, age and level of education) with misreporting of energy, protein and K intake of the DP, 24hR and FFQ were evaluated using linear regression analysis. Additionally, associations between other determinants, such as physical activity and smoking habits, and misreporting were investigated. SETTING: The Netherlands. SUBJECTS: One hundred and ninety-seven individuals aged 20-70 years. RESULTS: Higher BMI was associated with under-reporting of dietary intake assessed by the different dietary assessment methods for energy, protein and K, except for K by DP. Men tended to under-report protein by the DP, FFQ and 24hR, and persons of older age under-reported K but only by the 24hR and FFQ. When adjusted for the basic determinants, the other determinants did not show a consistent association with misreporting of energy or nutrients and by the different dietary assessment methods. CONCLUSIONS: As BMI was the only consistent determinant of misreporting, we conclude that BMI should always be taken into account when assessing and correcting dietary intake.

A systematic review of methods to assess intake of fruits and vegetables among healthy European adults and children: a DEDIPAC (DEterminants of DIet and Physical Activity) study.

OBJECTIVE: Evidence suggests that health benefits are associated with consuming recommended amounts of fruits and vegetables (F&V), yet standardised assessment methods to measure F&V intake are lacking. The current review aims to identify methods to assess F&V intake among children and adults in pan-European studies and inform the development of the DEDIPAC (DEterminants of DIet and Physical Activity) toolbox of methods suitable for use in future European studies. DESIGN: A literature search was conducted using three electronic databases and by hand-searching reference lists. English-language studies of any design which assessed F&V intake were included in the review. SETTING: Studies involving two or more European countries were included in the review. SUBJECTS: Healthy, free-living children or adults. RESULTS: The review identified fifty-one pan-European studies which assessed F&V intake. The FFQ was the most commonly used (n 42), followed by 24 h recall (n 11) and diet records/diet history (n 7). Differences existed between the identified methods; for example, the number of F&V items on the FFQ and whether potatoes/legumes were classified as vegetables. In total, eight validated instruments were identified which assessed F&V intake among adults, adolescents or children. CONCLUSIONS: The current review indicates that an agreed classification of F&V is needed in order to standardise intake data more effectively between European countries. Validated methods used in pan-European populations encompassing a range of European regions were identified. These methods should be considered for use by future studies focused on evaluating intake of F&V.

A systematic review of methods to assess intake of sugar-sweetened beverages among healthy European adults and children: a DEDIPAC (DEterminants of DIet and Physical Activity) study.

OBJECTIVE: Research indicates that intake of sugar-sweetened beverages (SSB) may be associated with negative health consequences. However, differences between assessment methods can affect the comparability of intake data across studies. The current review aimed to identify methods used to assess SSB intake among children and adults in pan-European studies and to inform the development of the DEDIPAC (DEterminants of DIet and Physical Activity) toolbox of methods suitable for use in future European studies. DESIGN: A literature search was conducted using three electronic databases and by hand-searching reference lists. English-language studies of any design which assessed SSB consumption were included in the review. SETTING: Studies involving two or more European countries were included in the review. SUBJECTS: Healthy, free-living children and adults. RESULTS: The review identified twenty-three pan-European studies which assessed intake of SSB. The FFQ was the most commonly used (n 24), followed by the 24 h recall (n 6) and diet records (n 1). There were several differences between the identified FFQ, including the definition of SSB used. In total, seven instruments that were tested for validity were selected as potentially suitable to assess SSB intake among adults (n 1), adolescents (n 3) and children (n 3). CONCLUSIONS: The current review highlights the need for instruments to use an agreed definition of SSB. Methods that were tested for validity and used in pan-European populations encompassing a range of countries were identified. These methods should be considered for use by future studies focused on evaluating consumption of SSB.

Effectiveness of Taste Lessons with and without additional experiential learning activities on children's willingness to taste vegetables.

This study assessed the effectiveness of the Dutch school programme Taste Lessons with and without additional experiential learning activities on children's willingness to taste unfamiliar vegetables. Thirty-three primary schools (877 children in grades 6-7 with a mean age of 10.3 years) participated in Taste Lessons Vegetable Menu (TLVM, lessons and extra activities), Taste Lessons (TL, lessons), or a control group. A baseline and follow-up measurement was used to assess for each child: number of four familiar and four unfamiliar vegetables tasted, quantity tasted, choice of vegetable of which to eat more, and number of vegetables willing to taste again later. Furthermore, children filled out a questionnaire on daily vegetable intake and food neophobia. Multilevel and Cox regression analyses were conducted to compare changes in the outcome measures between the three study groups. No significant intervention effects were found on willingness to taste unfamiliar vegetables. Neither were effects found on familiar vegetables, except for number of familiar vegetables tasted (p < 0.05). Furthermore, no significant intervention effects were found on daily vegetable consumption and food neophobia. These results indicate that more intensive school-based nutrition education activities are needed to increase children's willingness to taste unfamiliar vegetables and increase their vegetable intake.

Evaluation of a screener to assess diet quality in the Netherlands.

Generally, there is a need for short questionnaires to estimate diet quality in the Netherlands. We developed a thirty-four-item FFQ--the Dutch Healthy Diet FFQ (DHD-FFQ)--to estimate adherence to the most recent Dutch guidelines for a healthy diet of 2006 using the DHD-index. The objectives of the present study were to evaluate the DHD-index derived from the DHD-FFQ by comparing it with the index based on a reference method and to examine associations with participant characteristics, nutrient intakes and levels of cardiometabolic risk factors. Data of 1235 Dutch men and women, aged between 20 and 70 years, participating in the Nutrition Questionnaires plus study were used. The DHD-index was calculated from the DHD-FFQ and from a reference method consisting of a 180-item FFQ combined with a 24-h urinary Na excretion value. Ranking was studied using Spearman's correlations, and absolute agreement was studied using a Bland-Altman plot. Nutrient intakes derived from the 180-item FFQ were studied according to quintiles of the DHD-index using DHD-FFQ data. The correlation between the DHD-index derived from the DHD-FFQ and the reference method was 0·56 (95% CI 0·52, 0·60). The Bland-Altman plot showed a small mean overestimation of the DHD-index derived from the DHD-FFQ compared with the reference method. The DHD-index score was in the favourable direction associated with most macronutrient and micronutrient intakes when adjusted for energy intake. No associations between the DHD-index score and cardiometabolic risk factors were observed. In conclusion, the DHD-index derived from the DHD-FFQ was considered acceptable in ranking but relatively poor in individual assessment of diet quality.

A national FFQ for the Netherlands (the FFQ-NL 1.0): validation of a comprehensive FFQ for adults.

A standardised, national, 160-item FFQ, the FFQ-NL 1.0, was recently developed for Dutch epidemiological studies. The objective was to validate the FFQ-NL 1.0 against multiple 24-h recalls (24hR) and recovery and concentration biomarkers. The FFQ-NL 1.0 was filled out by 383 participants (25-69 years) from the Nutrition Questionnaires plus study. For each participant, one to two urinary and blood samples and one to five (mean 2·7) telephone-based 24hR were available. Group-level bias, correlation coefficients, attenuation factors, de-attenuated correlation coefficients and ranking agreement were assessed. Compared with the 24hR, the FFQ-NL 1.0 estimated the intake of energy and macronutrients well. However, it underestimated intakes of SFA and trans-fatty acids and alcohol and overestimated intakes of most vitamins by >5 %. The median correlation coefficient was 0·39 for energy and macronutrients, 0·30 for micronutrients and 0·30 for food groups. The FFQ underestimated protein intake by an average of 16 % and K by 5 %, relative to their urinary recovery biomarkers. Attenuation factors were 0·44 and 0·46 for protein and K, respectively. Correlation coefficients were 0·43-0·47 between (fatty) fish intake and plasma EPA and DHA and 0·24-0·43 between fruit and vegetable intakes and plasma carotenoids. In conclusion, the overall validity of the newly developed FFQ-NL 1.0 was acceptable to good. The FFQ-NL 1.0 is well suited for future use within Dutch cohort studies among adults.

A method for sensitivity analysis to assess the effects of measurement error in multiple exposure variables using external validation data.

BACKGROUND: Measurement error in self-reported dietary intakes is known to bias the association between dietary intake and a health outcome of interest such as risk of a disease. The association can be distorted further by mismeasured confounders, leading to invalid results and conclusions. It is, however, difficult to adjust for the bias in the association when there is no internal validation data. METHODS: We proposed a method to adjust for the bias in the diet-disease association (hereafter, association), due to measurement error in dietary intake and a mismeasured confounder, when there is no internal validation data. The method combines prior information on the validity of the self-report instrument with the observed data to adjust for the bias in the association. We compared the proposed method with the method that ignores the confounder effect, and with the method that ignores measurement errors completely. We assessed the sensitivity of the estimates to various magnitudes of measurement error, error correlations and uncertainty in the literature-reported validation data. We applied the methods to fruits and vegetables (FV) intakes, cigarette smoking (confounder) and all-cause mortality data from the European Prospective Investigation into Cancer and Nutrition study. RESULTS: Using the proposed method resulted in about four times increase in the strength of association between FV intake and mortality. For weakly correlated errors, measurement error in the confounder minimally affected the hazard ratio estimate for FV intake. The effect was more pronounced for strong error correlations. CONCLUSIONS: The proposed method permits sensitivity analysis on measurement error structures and accounts for uncertainties in the reported validity coefficients. The method is useful in assessing the direction and quantifying the magnitude of bias in the association due to measurement errors in the confounders.