Comparability of dietary patterns assessed by multiple dietary assessment methods: results from the 1946 British Birth Cohort

Comparing Self-Reported Dietary Intake to Provided Diet during a Randomized Controlled Feeding Intervention: A Pilot Study

Systematic and random errors based on self-reported diet may bias estimates of dietary intake. The objective of this pilot study was to describe errors in self-reported dietary intake by comparing 24 h dietary recalls to provided menu items in a controlled feeding study. This feeding study was a parallel randomized block design consisting of a standard diet (STD; 15% protein, 50% carbohydrate, 35% fat) followed by either a high-fat (HF; 15% protein, 25% carbohydrate, 60% fat) or a high-carbohydrate (HC; 15% protein, 75% carbohydrate, 10% fat) diet. During the intervention, participants reported dietary intake in 24 h recalls. Participants included 12 males (seven HC, five HF) and 12 females (six HC, six HF). The Nutrition Data System for Research was utilized to quantify energy, macronutrients, and serving size of food groups. Statistical analyses assessed differences in 24 h dietary recalls vs. provided menu items, considering intervention type (STD vs. HF vs. HC) (Student's t-test). Caloric intake was consistent between self-reported intake and provided meals. Participants in the HF diet underreported energy-adjusted dietary fat and participants in the HC diet underreported energy-adjusted dietary carbohydrates. Energy-adjusted protein intake was overreported in each dietary intervention, specifically overreporting beef and poultry. Classifying misreported dietary components can lead to strategies to mitigate self-report errors for accurate dietary assessment.

The efficacy of a blended intervention to improve physical activity and protein intake for optimal physical recovery after oncological gastrointestinal and lung cancer surgery, the Optimal Physical Recovery After Hospitalization (OPRAH) trial: study protocol for a randomized controlled multicenter trial

BACKGROUND

Improving physical activity, especially in combination with optimizing protein intake, after surgery has a potential positive effect on recovery of physical functioning in patients after gastrointestinal and lung cancer surgery. The aim of this randomized controlled trial is to evaluate the efficacy of a blended intervention to improve physical activity and protein intake after hospital discharge on recovery of physical functioning in these patients.

METHODS

In this multicenter single-blinded randomized controlled trial, 161 adult patients scheduled for elective gastrointestinal or lung cancer surgery will be randomly assigned to the intervention or control group. The purpose of the Optimal Physical Recovery After Hospitalization (OPRAH) intervention is to encourage self-management of patients in their functional recovery, by using a smartphone application and corresponding accelerometer in combination with coaching by a physiotherapist and dietician during three months after hospital discharge. Study outcomes will be measured prior to surgery (baseline) and one, four, eight, and twelve weeks and six months after hospital discharge. The primary outcome is recovery in physical functioning six months after surgery, and the most important secondary outcome is physical activity. Other outcomes include lean body mass, muscle mass, protein intake, symptoms, physical performance, self-reported limitations in activities and participation, self-efficacy, hospital readmissions and adverse events.

DISCUSSION

The results of this study will demonstrate whether a blended intervention to support patients increasing their level of physical activity and protein intake after hospital discharge improves recovery in physical functioning in patients after gastrointestinal and lung cancer surgery.

TRIAL REGISTRATION

The trial has been registered at the International Clinical Trials Registry Platform at 14-10-2021 with registration number NL9793. Trial registration data are presented in Table 1.

Paternal Diet before Conception and Its Social Determinants in the Elfe Cohort

This study aimed to characterize paternal diet during the peri-conception period and its associated characteristics. These cross-sectional analyses were based on 998 fathers from the French nationwide ELFE birth cohort recruited in 2011. Fathers’ diet before mothers’ pregnancies was assessed by a 46-item food frequency questionnaire. Six exploratory dietary patterns were identified by principal component analysis: “Diverse diet”, “Balanced”, “Alcohol”, “Snacking”, “Bread and cheese”, and “Processed products”. Older age was related to higher scores for the “Balanced”, “Alcohol”, and “Snacking” patterns, and high education level with high scores on the “Balanced” pattern and low scores on the “Processed products” pattern. Unemployment and having a first child were related to high scores on the “Alcohol” pattern. Smoking was positively related to “Alcohol” and “Processed products” patterns. A restrictive diet was associated with high scores on the “Balanced” and “Processed products” patterns and low scores on “Alcohol”, “Snacking”, and “Bread and cheese” patterns. Maternal dietary patterns, identified in a previous analysis, were moderately and positively related to the similar patterns among fathers. These findings are important for screening fathers at risk of a suboptimal diet and for accounting for this factor in future studies to examine the specific influence of paternal diet on a child’s health and development.

Comparison of Three Dietary Assessment Methods to Estimate Meat Intake as Part of a Meat Reduction Intervention among Adults in the UK

Food diaries are used to estimate meat intake at an individual level but it is unclear whether simpler methods would provide similar results. This study assessed the agreement between 7 day food diaries in which composite dishes were disaggregated to assess meat content (reference method), and two simpler methods: (1) frequency meal counts from 7 day food diaries; and (2) 7 day dietary recalls, each using standard estimated portion sizes. We compared data from a randomized controlled trial testing a meat reduction intervention. We used Bland-Altman plots to assess the level of agreement between methods at baseline and linear mixed-effects models to compare estimates of intervention effectiveness. At baseline, participants consumed 132 g/d (±75) of total meat; frequency meal counts and dietary recalls underestimated this by an average of 30 and 34 g/day, respectively. This was partially explained by an underestimation of the assumed portion size. The two simpler methods also underestimated the effect of the intervention, relative to control, though the significant effect of the intervention was unchanged. Simpler methods underestimated absolute meat intake but may be suitable for use in studies to measure the change in meat intake in individuals over time.

Relative Validity and Reproducibility of a Food Frequency Questionnaire for Assessing Dietary Patterns and Food Group Intake in Older New Zealand Adults: The Researching Eating, Activity, and Cognitive Health Study

BACKGROUND

Dietary pattern analysis considers the overall dietary intake and combinations of foods eaten. Valid and reproducible tools for determining dietary patterns are necessary to assess diet-disease relationships.

OBJECTIVE

This study evaluated the relative validity and reproducibility of the Researching Eating, Activity, and Cognitive Health (REACH) Study food frequency questionnaire (FFQ) specifically designed to identify dietary patterns in older adults.

DESIGN

A subset of participants from the REACH study completed two identical 109-item FFQs 1 month apart (FFQ1 and FFQ2) to assess reproducibility and a 4-day food record between FFQ administrations to assess relative validity. Foods from each dietary assessment tool were assigned to 57 food groups. Principal component analysis was applied to the food group consumption reported in each dietary assessment tool to derive dietary patterns.

PARTICIPANTS AND SETTING

Dietary data were collected (2018 and 2019) from a subset of the REACH study (n = 294, 37% men) aged 65 to 74 years, living in Auckland, New Zealand.

MAIN OUTCOME MEASURES

Daily intakes of 57 food groups and dietary patterns of older adults participating in REACH living in New Zealand.

STATISTICAL ANALYSIS

Agreement of dietary pattern loadings were assessed using Tucker's congruence coefficient. Agreement of dietary pattern scores and food group intakes were assessed using Spearman correlation coefficients (acceptable correlation rho = 0.20 to 0.49), weighted kappa statistic (acceptable statistic κ_w = 0.20 to 0.60), and Bland-Altman analysis, including mean difference, limits of agreement, plots, and slope of bias.

RESULTS

Three similar dietary patterns were identified from each dietary assessment tool: Mediterranean style, Western, and prudent. Congruence coefficients between factor loadings ranged from 0.54 to 0.80. Correlations of dietary pattern scores ranged from 0.47 to 0.59 (reproducibility) and 0.33 to 0.43 (validity) (all P values < 0.001); weighted kappa scores from 0.40 to 0.48 (reproducibility) and 0.27 to 0.37 (validity); limits of agreement from ± 1.79 to ± 2.09 (reproducibility) and ± 2.09 to ± 2.27 (validity); a negative slope of bias was seen in the prudent pattern for reproducibility and validity (P < 0.001).

CONCLUSIONS

The REACH FFQ generated dietary patterns with acceptable reproducibility and relative validity and therefore can be used to examine associations between dietary patterns and health outcomes in older New Zealand adults.

Diet Data Collected Using 48-h Dietary Recall: Within-and Between-Person Variation

Background and Aims: Forty-eight-hour dietary recall is a valuable source of information regarding food consumption in a population-based sample. This method covers 2 consecutive days in a single interview. Nevertheless, the number of assessments and the sample size necessary to estimate usual intake are unknown. We aimed to assess sources of variation, sample sizes, and numbers of days necessary to estimate usual nutrient intake using the 48-h dietary recall.

Methods: This was a population-based cross-sectional study including 237 participants, 11–90 years old, selected using multistage probabilistic sampling to obtain data using 48-h dietary recall. Analysis of variance was used to calculate within- and between-person variation and determine the statistical parameters necessary to calculate sample size and the number of days required to calculate the usual energy and nutrient intake.

Results: Within-person variation was generally lower than between-person variation, except for calcium (CVw2 = 40.8; CVb2 = 38.4%), magnesium (CVw2 = 27.4; CVb2 = 18.7%), and monounsaturated fat (CVw2 = 20.0; CVb2 = 17.3%) for the entire group and magnesium for women (CVw2 = 28.3; CVb2 = 91.8%). The number of days and sample size required to determine usual energy and nutrient intake varied substantially with gender and age (e.g., vitamin C in women N = 9, in men N = 1,641).

Conclusions: Energy and nutrient intake assessment using the 48-h dietary recall misrepresents within-person variation but can generate acceptable results for between-person variation. The calculation of sample size and number of days required to determine usual energy and nutrient intake might have been affected by inadequate assessment of the within-person variation.

Dietary Patterns, Their Nutrients, and Associations with Socio-Demographic and Lifestyle Factors in Older New Zealand Adults

Dietary patterns analyse combinations of foods eaten. This cross-sectional study identified dietary patterns and their nutrients. Associations between dietary patterns and socio-demographic and lifestyle factors were examined in older New Zealand adults. Dietary data (109-item food frequency questionnaire) from the Researching Eating, Activity and Cognitive Health (REACH) study (n = 367, 36% male, mean age = 70 years) were collapsed into 57 food groups. Using principal component analysis, three dietary patterns explained 18% of the variation in diet. Dietary pattern associations with sex, age, employment, living situation, education, deprivation score, physical activity, alcohol, and smoking, along with energy-adjusted nutrient intakes, were investigated using regression analysis. Higher 'Mediterranean' dietary pattern scores were associated with being female, higher physical activity, and higher education (p < 0.001, R2 = 0.07). Higher 'Western' pattern scores were associated with being male, higher alcohol intake, living with others, and secondary education (p < 0.001, R2 = 0.16). Higher 'prudent' pattern scores were associated with higher physical activity and lower alcohol intake (p < 0.001, R2 = 0.15). There were positive associations between beta-carotene equivalents, vitamin E, and folate and 'Mediterranean' dietary pattern scores (p < 0.0001, R2 ≥ 0.26); energy intake and 'Western' scores (p < 0.0001, R2 = 0.43); and fibre and carbohydrate and 'prudent' scores (p < 0.0001, R2 ≥ 0.25). Socio-demographic and lifestyle factors were associated with dietary patterns. Understanding relationships between these characteristics and dietary patterns can assist in health promotion.

Reproducibility and Validity of A Posteriori Dietary Patterns: A Systematic Review

The effective use of dietary patterns (DPs) remains limited. There is a need to assess their consistency over multiple administrations of the same dietary source, different dietary sources, or across different studies. Similarly, their generalizability should be based on a previous assessment of DP construct validity. However, to date, no systematic reviews of reproducibility and validity of a posteriori DPs have been carried out. In addition, several methodological questions related to their identification are still open and prevent a fair comparison of epidemiological results on DPs and disease. A systematic review of the literature on the PubMed database was conducted. We identified 218 articles, 64 of which met the inclusion criteria. Of these, the 38 articles dealing with reproducibility and relative and construct validity of DPs were included. These articles (published in 1999-2017, 53% from 2010 onwards) were based on observational studies conducted worldwide. The 14 articles that assessed DP reproducibility across different statistical solutions examined different research questions. Included were: the number of food groups or subjects; input variable format (as well as adjustment for energy intake); algorithms and the number of DPs to retain in cluster analysis; rotation method; and score calculation in factor analysis. However, we identified at most 3 articles per research question on DP reproducibility across statistical solutions. From another 15 articles, reproducibility of DPs over shorter (≤1 y) time periods was generally good and higher than DP relative validity (as measured across different dietary sources). Confirmatory factor analysis was used in 15 of the included articles. It provided reassuring results in identifying valid dietary constructs characterizing the populations under consideration. Based on the available evidence, only suggestive conclusions can be derived on reproducibility across different statistical solutions. Nevertheless, most identified DPs showed good reproducibility, fair relative validity, and good construct validity.

A systematic review of reviews identifying UK validated dietary assessment tools for inclusion on an interactive guided website for researchers: www.nutritools.org

Background: Health researchers may struggle to choose suitable validated dietary assessment tools (DATs) for their target population. The aim of this review was to identify and collate information on validated UK DATs and validation studies for inclusion on a website to support researchers to choose appropriate DATs.Design: A systematic review of reviews of DATs was undertaken. DATs validated in UK populations were extracted from the studies identified. A searchable website was designed to display these data. Additionally, mean differences and limits of agreement between test and comparison methods were summarized by a method, weighting by sample size.Results: Over 900 validation results covering 5 life stages, 18 nutrients, 6 dietary assessment methods, and 9 validation method types were extracted from 63 validated DATs which were identified from 68 reviews. These were incorporated into www.nutritools.org. Limits of agreement were determined for about half of validations. Thirty four DATs were FFQs. Only 17 DATs were validated against biomarkers, and only 19 DATs were validated in infant/children/adolescents.Conclusions: The interactive www.nutritools.org website holds extensive validation data identified from this review and can be used to guide researchers to critically compare and choose a suitable DAT for their research question, leading to improvement of nutritional epidemiology research.

Habit strength and between-meal snacking in daily life: the moderating role of level of education

Objective

Recent research emphasizes the importance of habit in explaining patterns of energy intake and choices of consumption. However, the nature of the association between habit strength and snacking has not been explored for all types of between-meal snacks.

Design

Multilevel linear techniques were used to: (i) examine the association between habit strength and moment-to-moment energy intake (kilocalories) from snacks in daily life; and (ii) determine whether gender, age, level of education and BMI moderate the association between habit strength and moment-to-moment energy intake from snacks. A smartphone application based on the experience sampling method was used to map momentary between-meal snack intake in the context of daily life. Demographics and habit strength were assessed with an online composite questionnaire.

Setting

This research was performed in the Netherlands in the natural environment of participants’ daily life.

Subjects

Adults (n 269) aged 20–50 years.

Results

Habit strength was significantly associated with moment-to-moment energy intake from between-meal snacks in daily life: the higher the strength of habit to snack between meals, the higher the amount of momentary energy intake from snacks. The association between habit strength and moment-to-moment energy intake from snacks was moderated by education level. Additional analyses showed that habit strength was significantly associated with moment-to-moment energy intake from between-meal snacks in the low to middle level of education group.

Conclusions

It is recommended to address habitual between-meal snacking in future interventions targeting low- to middle-educated individuals.

Diet Quality and Sarcopenia in Older Adults: A Systematic Review

The increasing recognition of sarcopenia, the age-related loss of skeletal muscle mass and function (muscle strength and physical performance), as a determinant of poor health in older age, has emphasized the importance of understanding more about its aetiology to inform strategies both for preventing and treating this condition. There is growing interest in the effects of modifiable factors such as diet; some nutrients have been studied but less is known about the influence of overall diet quality on sarcopenia. We conducted a systematic review of the literature examining the relationship between diet quality and the individual components of sarcopenia, i.e., muscle mass, muscle strength and physical performance, and the overall risk of sarcopenia, among older adults. We identified 23 studies that met review inclusion criteria. The studies were diverse in terms of the design, setting, measures of diet quality, and outcome measurements. A small body of evidence suggested a relationship between "healthier" diets and better muscle mass outcomes. There was limited and inconsistent evidence for a link between "healthier" diets and lower risk of declines in muscle strength. There was strong and consistent observational evidence for a link between "healthier" diets and lower risk of declines in physical performance. There was a small body of cross-sectional evidence showing an association between "healthier" diets and lower risk of sarcopenia. This review provides observational evidence to support the benefits of diets of higher quality for physical performance among older adults. Findings for the other outcomes considered suggest some benefits, although the evidence is either limited in its extent (sarcopenia) or inconsistent/weak in its nature (muscle mass, muscle strength). Further studies are needed to assess the potential of whole-diet interventions for the prevention and management of sarcopenia.

The effects of acceptance and commitment therapy on eating behavior and diet delivered through face-to-face contact and a mobile app: a randomized controlled trial

Background

Internal motivation and good psychological capabilities are important factors in successful eating-related behavior change. Thus, we investigated whether general acceptance and commitment therapy (ACT) affects reported eating behavior and diet quality and whether baseline perceived stress moderates the intervention effects.

Methods

Secondary analysis of unblinded randomized controlled trial in three Finnish cities. Working-aged adults with psychological distress and overweight or obesity in three parallel groups: (1) ACT-based Face-to-face (n = 70; six group sessions led by a psychologist), (2) ACT-based Mobile (n = 78; one group session and mobile app), and (3) Control (n = 71; only the measurements). At baseline, the participants’ (n = 219, 85% females) mean body mass index was 31.3 kg/m² (SD = 2.9), and mean age was 49.5 years (SD = 7.4). The measurements conducted before the 8-week intervention period (baseline), 10 weeks after the baseline (post-intervention), and 36 weeks after the baseline (follow-up) included clinical measurements, questionnaires of eating behavior (IES-1, TFEQ-R18, HTAS, ecSI 2.0, REBS), diet quality (IDQ), alcohol consumption (AUDIT-C), perceived stress (PSS), and 48-h dietary recall. Hierarchical linear modeling (Wald test) was used to analyze the differences in changes between groups.

Results

Group x time interactions showed that the subcomponent of intuitive eating (IES-1), i.e., Eating for physical rather than emotional reasons, increased in both ACT-based groups (p = .019); the subcomponent of TFEQ-R18, i.e., Uncontrolled eating, decreased in the Face-to-face group (p = .020); the subcomponent of health and taste attitudes (HTAS), i.e., Using food as a reward, decreased in the Mobile group (p = .048); and both subcomponent of eating competence (ecSI 2.0), i.e., Food acceptance (p = .048), and two subcomponents of regulation of eating behavior (REBS), i.e., Integrated and Identified regulation (p = .003, p = .023, respectively), increased in the Face-to-face group. Baseline perceived stress did not moderate effects on these particular features of eating behavior from baseline to follow-up. No statistically significant effects were found for dietary measures.

Conclusions

ACT-based interventions, delivered in group sessions or by mobile app, showed beneficial effects on reported eating behavior. Beneficial effects on eating behavior were, however, not accompanied by parallel changes in diet, which suggests that ACT-based interventions should include nutritional counseling if changes in diet are targeted.

Trial registration

ClinicalTrials.gov (NCT01738256), registered 17 August, 2012.

Electronic supplementary material

The online version of this article (10.1186/s12966-018-0654-8) contains supplementary material, which is available to authorized users.

Affect and between-meal snacking in daily life: the moderating role of gender and age

OBJECTIVE

Affect-related energy intake from snacks remains relatively unexplored in daily life. This study examines the associations between momentary positive affect (PA) and momentary negative affect (NA) and subsequent energy intake from snacks. In addition, the moderating role of BMI, gender, age and level of education is investigated.

DESIGN

Adults (N = 269), aged 20-50, participated in this study. Demographics were assessed in an online composite questionnaire. An experience sampling smartphone application was used to map momentary NA/PA and energy intake (kilocalories) from snacks in the context of daily life.

MAIN OUTCOME MEASURES

Energy intake from moment-to-moment self-reported snacks in real-life settings.

RESULTS

A significant negative main effect of momentary NA on moment-to-moment energy intake was found. The higher the momentary NA, the lower the subsequent amount of kilocalories consumed. There was no main effect with regard to PA. Interaction analyses showed that men decreased their energy intake after experiencing NA, and increased their intake after experiencing PA. No associations were found in women. Additionally, young adults (20-30) increased their energy intake after experiencing PA. No associations were found in the other age groups.

CONCLUSION

Interventions aiming at reducing energy intake might also address PA-related snacking in young adults and men.

Associations between dietary patterns, socio-demographic factors and anthropometric measurements in adult New Zealanders: an analysis of data from the 2008/09 New Zealand Adult Nutrition Survey

PURPOSE

To investigate associations between dietary patterns, socio-demographic factors and anthropometric measurements in adult New Zealanders.

METHODS

Dietary patterns were identified using factor analysis in adults 15 years plus (n = 4657) using 24-h diet recall data from the 2008/09 New Zealand Adult Nutrition Survey. Multivariate regression was used to investigate associations between dietary patterns and age, gender and ethnicity. After controlling for demographic factors, associations between dietary patterns and food insecurity, deprivation, education, and smoking were investigated. Associations between dietary patterns and body mass index and waist circumference were examined adjusting for demographic factors, smoking and energy intake.

RESULTS

Two dietary patterns were identified. 'Healthy' was characterised by breakfast cereal, low fat milk, soy and rice milk, soup and stock, yoghurt, bananas, apples, other fruit and tea, and low intakes of pies and pastries, potato chips, white bread, takeaway foods, soft drinks, beer and wine. 'Traditional' was characterised by beef, starchy vegetables, green vegetables, carrots, tomatoes, savoury sauces, regular milk, cream, sugar, tea and coffee, and was low in takeaway foods. The 'healthy' pattern was positively associated with age, female gender, New Zealand European or other ethnicity, and a secondary school qualification, and inversely associated with smoking, food insecurity, area deprivation, BMI and waist circumference. The 'traditional' pattern was positively associated with age, male gender, smoking, food insecurity and inversely associated with a secondary school qualification.

CONCLUSIONS

A 'Healthy' dietary pattern was associated with higher socio-economic status and reduced adiposity, while the 'traditional' pattern was associated with lower socio-economic status.

Dietary patterns in the Avon Longitudinal Study of Parents and Children

Publications from the Avon Longitudinal Study of Parents and Children that used empirically derived dietary patterns were reviewed. The relationships of dietary patterns with socioeconomic background and childhood development were examined. Diet was assessed using food frequency questionnaires and food records. Three statistical methods were used: principal components analysis, cluster analysis, and reduced rank regression. Throughout childhood, children and parents have similar dietary patterns. The "health-conscious" and "traditional" patterns were associated with high intakes of fruits and/or vegetables and better nutrient profiles than the "processed" patterns. There was evidence of tracking in childhood diet, with the "health-conscious" patterns tracking most strongly, followed by the "processed" pattern. An "energy-dense, low-fiber, high-fat" dietary pattern was extracted using reduced rank regression; high scores on this pattern were associated with increasing adiposity. Maternal education was a strong determinant of pattern score or cluster membership; low educational attainment was associated with higher scores on processed, energy-dense patterns in both parents and children. The Avon Longitudinal Study of Parents and Children has provided unique insights into the value of empirically derived dietary patterns and has demonstrated that they are a useful tool in nutritional epidemiology.

Dietary assessment methods for intakes of iron, calcium, selenium, zinc and iodine

The EURopean micronutrient RECommendations Aligned (EURRECA) Network of Excellence is working towards developing aligned micronutrient recommendations across Europe. The purpose of the present study was to conduct a review of methods used in validation studies carried out in adults assessing dietary intake of EURRECA priority minerals. A search strategy and inclusion criteria were defined and a scoring system was developed to rate the quality of each validation study that produced a quality index with possible scores obtained ranging from 0.5 to 7. A MEDLINE and EMBASE literature review was conducted. Articles/validation studies meeting the inclusion criteria included: 79/88 for Fe; 95/104 for Ca; 13/15 for Se; 29/30 for Zn; 7/9 for iodine. The most frequently used method to ascertain dietary intake was the Food Frequency Questionnaire (FFQ), whereas dietary records (DR) and 24 h recalls were the most used reference methods. The correlation coefficients (CC) between study mineral intakes estimated by FFQ and the reference method were weighted according to the study's quality index and obtained acceptable to good ratings, ranging from 0.36 to 0.60 when the reference method was DR and from 0.41 to 0.58 when the reference was 24 h recalls. A minority of studies (n 9) used biomarkers for validation and among these, five included iodine obtaining a CC of 0.47. The FFQ was seen as a valid method for assessing mineral intake, particularly for Ca and, to a lower extent, for iodine and Zn. Se and Fe showed only acceptable correlations. The present review provides new insights regarding the characteristics that assessment methods for dietary mineral intakes should fulfil.

Dietary patterns obtained through principal components analysis: the effect of input variable quantification

Principal components analysis (PCA) is a popular method for deriving dietary patterns. A number of decisions must be made throughout the analytic process, including how to quantify the input variables of the PCA. The present study aims to compare the effect of using different input variables on the patterns extracted using PCA on 3-d diet diary data collected from 7473 children, aged 10 years, in the Avon Longitudinal Study of Parents and Children. Four options were examined: weight consumed of each food group (g/d), energy-adjusted weight, percentage contribution to energy of each food group and binary intake (consumed/not consumed). Four separate PCA were performed, one for each intake measurement. Three or four dietary patterns were obtained from each analysis, with at least one component that described 'more healthy' and 'less healthy' diets and one component that described a diet with high consumption of meat, potatoes and vegetables. There were no obvious differences between the patterns derived using percentage energy as a measurement and adjusting weight for total energy intake, compared to those derived using gram weights. Using binary input variables yielded a component that loaded positively on reduced fat and reduced sugar foods. The present results suggest that food intakes quantified by gram weights or as binary variables both resulted in meaningful dietary patterns and each method has distinct advantages: weight takes into account the amount of each food consumed and binary intake appears to describe general food preferences, which are potentially easier to modify and useful in public health settings.

The associations between feeding difficulties and behaviours and dietary patterns at 2 years of age: the ALSPAC cohort

Little is known about the dietary patterns of toddlers. This period of life is important for forming good dietary habits later in life. Using dietary data collected via food frequency questionnaire (FFQ) at 2 years of age, we examined the dietary patterns of children from the Avon Longitudinal Study of Parents and Children (ALSPAC). Principal component analysis was performed for 9599 children and three patterns were extracted: 'family foods' associated with traditional British family foods such as meat, fish, puddings, potatoes and vegetables; 'sweet and easy' associated with foods high in sugar (sweets, chocolate, fizzy drinks, flavoured milks) and foods requiring little preparation (crisps, potatoes, baked beans, peas, soup); 'health conscious' associated with fruit, vegetables, eggs, nuts and juices. We found clear associations between dietary pattern scores and socio-demographic variables, with maternal education being the most important. Higher levels of education were associated with higher scores on both the 'family foods' and the 'health conscious' patterns, and decreased scores on the 'sweet and easy' pattern. Relationships were evident between dietary pattern scores and various feeding difficulties and behaviours. Notably, children who were introduced late to lumpy (chewy) solids (after 9 months) scored lower on both the 'family foods' and the 'health conscious' patterns. Further analyses are required to determine the temporal relationship between perceived feeding difficulties and behaviours, and it will be important to assess the contribution of the age of introduction to lumpy solids to these relationships.

Dietary patterns and bone mineral status in young adults: the Northern Ireland Young Hearts Project

Studies of individual nutrients or foods have revealed much about dietary influences on bone. Multiple food or nutrient approaches, such as dietary pattern analysis, could offer further insight but research is limited and largely confined to older adults. We examined the relationship between dietary patterns, obtained by a posteriori and a priori methods, and bone mineral status (BMS; collective term for bone mineral content (BMC) and bone mineral density (BMD)) in young adults (20-25 years; n 489). Diet was assessed by 7 d diet history and BMD and BMC were determined at the lumbar spine and femoral neck (FN). A posteriori dietary patterns were derived using principal component analysis (PCA) and three a priori dietary quality scores were applied (dietary diversity score (DDS), nutritional risk score and Mediterranean diet score). For the PCA-derived dietary patterns, women in the top compared to the bottom fifth of the 'Nuts and Meat' pattern had greater FN BMD by 0·074 g/cm(2) (P = 0·049) and FN BMC by 0·40 g (P = 0·034) after adjustment for confounders. Similarly, men in the top compared to the bottom fifth of the 'Refined' pattern had lower FN BMC by 0·41 g (P = 0·049). For the a priori DDS, women in the top compared to the bottom third had lower FN BMD by 0·05 g/cm(2) after adjustments (P = 0·052), but no other relationships with BMS were identified. In conclusion, adherence to a 'Nuts and Meat' dietary pattern may be associated with greater BMS in young women and a 'Refined' dietary pattern may be detrimental for bone health in young men.

Parents' dietary patterns are significantly correlated: findings from the Melbourne Infant Feeding Activity and Nutrition Trial Program

The objectives of the present study were to identify dietary patterns independently in first-time mothers and fathers, and to examine whether these patterns were correlated within families. Dietary intakes were collected at baseline in the Melbourne Infant Feeding Activity and Nutrition Trial Program using a validated FFQ in 454 pairs of first-time mothers and fathers. Education level was reported in associated questionnaires. Principal components analyses included frequencies of fifty-five food groups and were performed independently in mothers and fathers. Spearman's correlation coefficients were used to assess associations between dietary pattern scores. A total of four dietary patterns were identified in mothers and fathers. Of these, three dietary patterns had similar characteristics between these two populations, namely ‘Fruits and vegetables’, ‘High-energy snack and processed foods’, ‘High-fat foods’ in mothers; and ‘Fruits’, ‘High-energy snack and processed foods’, ‘High-fat foods’ in fathers. The following two additional patterns were identified: ‘Cereals and sweet foods’ in mothers and ‘Potatoes and vegetables’ in fathers. Patterns incorporating healthier food items were found to be positively associated with parent education. An inverse association with education was found for the ‘High-fat foods’ and ‘High-energy snack and processed foods’ dietary patterns. Qualitatively similar patterns between corresponding mothers and fathers were the most strongly correlated (ρ = 0·34–0·45, P < 0·001). There were some differences in dietary patterns between mothers and fathers, suggesting that it is worth deriving patterns separately when considering couples, and more generally between men and women. Exploring how these various patterns correlate within households provides important insights to guide the development and implementation of family-based interventions.

Dietary patterns of men in ALSPAC: associations with socio-demographic and lifestyle characteristics, nutrient intake and comparison with women's dietary patterns

OBJECTIVE

The aim of this study is to obtain distinct dietary patterns using principal components analysis (PCA) in men taking part in the Avon Longitudinal Study of Parents and Children and to determine the associations with (a) the patterns derived in the study women (the men's partners), (b) socio-demographic and lifestyle factors and (c) estimated nutrient intakes.

DESIGN AND METHODS

A total of 4681 men taking part in a population-based cohort study recorded their current frequency of food consumption through questionnaire. Dietary patterns were identified using PCA, and scores were calculated for each pattern. A wide variety of social and demographic characteristics and lifestyle factors were also collected through self-completion questionnaire.

RESULTS

Four dietary patterns were established: 'health conscious', 'traditional', 'processed/confectionery' and 'semi-vegetarian'. There were relatively strong correlations and levels of agreement between the 'health conscious' and 'vegetarian' style patterns in men and women (P<0.001). Strong associations were evident between several socio-demographic variables and the dietary patterns, similar to those earlier reported in women. Finally, nutrient intakes were plausibly associated with dietary pattern scores.

CONCLUSIONS

Distinct dietary patterns in men have been identified using PCA that are similar, but not identical to those obtained in their partners at the same time point. Researchers should always consider stratifying by gender when examining dietary patterns. This study will form the basis for further work investigating the associations between parental and child dietary patterns.

Dietary patterns and adult asthma: population-based case-control study

BACKGROUND

Epidemiological studies of diet and asthma have focused on relations with intakes of individual nutrients and foods and evidence has been conflicting. Few studies have examined associations with dietary patterns.

METHODS

We carried out a population-based case-control study of asthma in adults aged between 16 and 50 in South London, UK. Information about usual diet was obtained by food frequency questionnaire and we used principal components analysis to define five dietary patterns in controls. We used logistic and linear regression, controlling for confounders, to relate these patterns to asthma, asthma severity, rhinitis and chronic bronchitis in 599 cases and 854 controls.

RESULTS

Overall, there was weak evidence that a 'vegetarian' dietary pattern was positively associated with asthma [adjusted odds ratio comparing top vs bottom quintile of pattern score 1.43 (95% CI: 0.93-2.20), P trend 0.075], and a 'traditional' pattern (meat and vegetables) was negatively associated [OR 0.68 (0.45-1.03), P trend 0.071]. These associations were stronger amongst nonsupplement users (P trend 0.030 and 0.001, respectively), and the association with the 'vegetarian' pattern was stronger amongst whites (P trend 0.008). No associations were observed with asthma severity. A 'prudent' dietary pattern (wholemeal bread, fish and vegetables) was positively associated with chronic bronchitis [OR 2.61 (1.13-6.05), P trend 0.025], especially amongst nonsupplement users (P trend 0.002).

CONCLUSIONS

Overall there were no clear relations between dietary patterns and adult asthma; associations in nonsupplement users and whites require confirmation. The finding for chronic bronchitis was unexpected and also requires replication.

Contaminated fish consumption in California's Central Valley Delta

Extensive mercury contamination and angler selection of the most contaminated fish species coincide in California's Central Valley. This has led to a policy conundrum: how to balance the economic and cultural impact of advising subsistence anglers to eat less fish with the economic cost of reducing the mercury concentrations in fish? State agencies with regulatory and other jurisdictional authority lack sufficient data and have no consistent approach to this problem. The present study focused on a critical and contentious region in California's Central Valley (the Sacramento-San Joaquin Rivers Delta) where mercury concentrations in fish and subsistence fishing rates are both high. Anglers and community members were surveyed for their fish preferences, rates of consumption, the ways that they receive health information, and basic demographic information. The rates of fish consumption for certain ethnicities were higher than the rates used by state agencies for planning pollution remediation. A broad range of ethnic groups were involved in catching and eating fish. The majority of anglers reported catching fish in order to feed to their families, including children and women of child-bearing age. There were varied preferences for receiving health information and no correlation between knowledge of fish contamination and rates of consumption. Calculated rates of mercury intake by subsistence anglers were well above the EPA reference dose. The findings here support a comprehensive policy strategy of involvement of the diverse communities in decision-making about education and clean-up and an official recognition of subsistence fishers in the region.

Long-term dietary patterns and carotid artery intima media thickness: the Cardiovascular Risk in Young Finns Study

A whole-diet approach has proven useful for characterising dietary exposure in cardiovascular epidemiology research. In our previous analyses, we found dietary patterns to be significant determinants of CVD risk factor levels among the Cardiovascular Risk in Young Finns cohort. We investigated the associations of major dietary patterns with carotid intima media thickness (IMT), a subclinical predictor of CVD, in healthy adults. The Young Finns Study is an ongoing, prospective cohort study with a 21-year follow-up to date. The subjects were children and adolescents at baseline in 1980 (aged 3-18 years), and all had reached adulthood by the latest follow-up in 2001 (aged 24-39 years). Complete dietary data from the years 1980, 1986 and 2001 and outcome data from the year 2001 were obtained from 785 subjects. The long-term average pattern score for a traditional dietary pattern (characterised by high consumption of rye, potatoes, butter, sausages, milk and coffee) was associated with IMT especially among subjects with a low score for the health-conscious dietary pattern (characterised by high consumption of vegetables, legumes and nuts, rye, tea, cheese and other dairy products). In multivariable regression analyses using long-term pattern scores as predictors, the traditional dietary pattern was independently associated with IMT in men (P < 0.01), but not in women (P = 0.66). Long-term adherence to traditional food choices seems to increase the risk of developing subclinical atherosclerosis among Finnish men.

Validation of an FFQ to assess dietary protein intake in type 2 diabetic subjects attending primary health-care services in Mali

OBJECTIVE

To validate a 53-item quantitative FFQ (QFFQ) for the assessment of dietary protein intake in type 2 diabetic outpatients in Bamako, Mali.

DESIGN

Consumption of protein-containing foods over the week preceding the interview was measured with a 7d QFFQ and compared with intakes measured with 48-h recalls.

SETTING

Centre National de Lutte contre le Diabète.

SUBJECTS

Seventeen male and forty female adults with type 2 diabetes.

RESULTS

Correlation between protein intakes estimated using the QFFQ and 48h recalls was 0.63 (P < 0.0001). There was no significant difference between the two methods concerning the total protein daily intakes and intakes per kilogram of body weight. The QFFQ indicated that foods of animal origin were a lesser source of protein. Animal protein intake did not differ between men and women but sources did. In men, the main sources were beef (54 % of total animal protein), fish (15 %) and milk powder (8 %). In women, the principal sources were fish (28 %), beef (20 %) and birds (13 %). In contrast, plant protein intake was significantly higher in men than in women (P = 0.01), but the same plant foods contributed in similar proportions for both genders, rice being by far the greatest source (47 % of plant protein in men, 53 % in women).

CONCLUSION

The QFFQ developed in this study is a valid tool to evaluate dietary protein intakes in Malian diabetic subjects. While the total protein intakes were low in both men and women, differences in choices and amounts of protein food sources were shown.

Under-reporting of energy intake is more prevalent in a healthy dietary pattern cluster

The aim of the present study was to determine whether under-reporting rates vary between dietary pattern clusters. Subjects were sixty-five Brazilian women. During 3 weeks, anthropometric data were collected, total energy expenditure (TEE) was determined by the doubly labelled water method and diet was measured. Energy intake (EI) and the daily frequency of consumption per 1000 kJ of twenty-two food groups were obtained from a FFQ. These frequencies were entered into a cluster analysis procedure in order to obtain dietary patterns. Under-reporters were defined as those who did not lose more than 1 kg of body weight during the study and presented EI:TEE less than 0.82. Three dietary pattern clusters were identified and named according to their most recurrent food groups: sweet foods (SW), starchy foods (ST) and healthy (H). Subjects from the healthy cluster had the lowest mean EI:TEE (SW = 0.86, ST = 0.71 and H = 0.58; P = 0.003) and EI - TEE (SW = - 0.49 MJ, ST = - 3.20 MJ and H = - 5.08 MJ; P = 0.008). The proportion of under-reporters was 45.2 (95 % CI 35.5, 55.0) % in the SW cluster; 58.3 (95 % CI 48.6, 68.0) % in the ST cluster and 70.0 (95 % CI 61.0, 79) % in the H cluster (P = 0.34). Thus, in Brazilian women, under-reporting of EI is not uniformly distributed among dietary pattern clusters and tends to be more severe among subjects from the healthy cluster. This cluster is more consistent with both dietary guidelines and with what lay individuals usually consider 'healthy eating'.

Association between nocturnal sleep duration, body fatness, and dietary intake in Greek women

OBJECTIVE

We investigated the association of nocturnal sleep duration with body fatness, energy, and macronutrient intake in female adults.

METHODS

Thirty healthy Greek women 30-60 y of age and under no medication were recruited for an observational, cross-sectional study in Athens, Greece, in 2005. Participants' height, weight, skinfold thickness, and waist and hip circumferences were measured. All subjects completed a Sleep Habits Questionnaire and a 7-d sleep diary to estimate nocturnal sleep duration. Two 24-h dietary recall interviews were conducted to assess dietary intake.

RESULTS

Nocturnal sleep duration was negatively associated with body fatness (r = -0.614, P < 0.001) and body mass index (r = -0.401, P < 0.05). Each 1-h decrease in nocturnal sleep duration was associated with a significant increase in body fat of 2.8% (95% confidence interval -4.6 to -1.0) when the effects of age and energy intake were held constant. A weak positive association between sleep duration and saturated fat was observed (r = 0.392, P < 0.05). However, no significant association of sleep duration with certain central obesity indices, energy intake, or a preference for fat or carbohydrate consumption was found.

CONCLUSION

The present study identifies an independent negative association of nocturnal sleep duration with body fatness. Therefore, the shorter the sleep duration, the greater is the body fatness. The hypothesis that sleep duration is associated with energy intake and a preference for fat or carbohydrate consumption was not supported.

Adjusting for energy intake in dietary pattern investigations using principal components analysis

OBJECTIVE

The effect of energy adjustment on variables entered into principal component analysis (PCA) to derive dietary patterns has received little attention.

DESIGN AND METHODS

As part of regular self-completion questionnaires, used in the Avon Longitudinal Study of Parents and Children, pregnant women were asked to record the frequency of consumption of a variety of food items. A total of 12 053 women completed the questionnaire. Individual dietary types were identified using PCA, before and after adjusting the food variables for energy intake. Associations with estimated nutrient intakes and with birthweight were examined for the two solutions and when energy adjustment was performed at a later stage of the analysis.

RESULTS

Slight differences were seen in terms of the components extracted and the factor loadings obtained. The associations with nutrient intakes showed that there was a general reduction in the size of the correlation coefficients for the energy-adjusted components compared to the unadjusted components. There did not appear to be any difference in the size of the effects of the dietary pattern scores on birthweight, whether energy was adjusted for before entry into the PCA or after.

CONCLUSIONS

In this sample, it is not necessary to adjust for energy intake before entry into a PCA analysis to determine dietary patterns when using food frequency questionnaire data. Effects of energy intake can be determined at a later stage in the analytical process.This study determines the effect of adjusting for energy on dietary patterns resulting from PCA and the subsequent effect on future outcomes.

Dietary patterns in pregnancy and associations with socio-demographic and lifestyle factors

OBJECTIVE

To obtain distinct dietary patterns in the third trimester of pregnancy using principal components analysis (PCA); to determine associations with socio-demographic and lifestyle factors.

DESIGN AND METHODS

A total of 12 053 pregnant women partaking in a population-based cohort study recorded current frequency of food consumption via questionnaire in 1991-1992. Dietary patterns identified using PCA were related to social and demographic characteristics and lifestyle factors.

RESULTS

Five dietary patterns were established and labelled to best describe the types of diet being consumed in pregnancy. The 'health conscious' component described a diet based on salad, fruit, rice, pasta, breakfast cereals, fish, eggs, pulses, fruit juices, white meat and non-white bread. The 'traditional' component loaded highly on all types of vegetables, red meat and poultry. The 'processed' component was associated with high-fat processed foods. The 'confectionery' component was characterized by snack foods with high sugar content and the final 'vegetarian' component loaded highly on meat substitutes, pulses, nuts and herbal tea and high negative loadings were seen with red meat and poultry. There were strong associations between various socio-demographic variables and all dietary components; in particular, a 'health conscious' diet was positively associated with increasing education and age and non-white women. There was a negative association with increased parity, single, non-working women, those who smoked and who were overweight pre-pregnancy. Opposite associations were seen with the 'processed' component.

CONCLUSIONS

Distinct dietary patterns in pregnancy have been identified. There is clear evidence of social patterning associated with the dietary patterns, these social factors need to be accounted for in future studies using dietary patterns. This study will form the basis for further work investigating pregnancy outcome.

Major dietary patterns and cardiovascular risk factors from childhood to adulthood. The Cardiovascular Risk in Young Finns Study

Studies on the impact of single nutrients on the risk of CVD have often given inconclusive results. Recent research on dietary patterns has offered promising information on the effects of diet as a whole on the risk of CVD. The Cardiovascular Risk in Young Finns Study is an ongoing, prospective cohort study with a 21-year follow-up to date. The subjects were children and adolescents at baseline (3-18 years, n 1768) and adults at the latest follow-up study (24-39 years, n 1037). We investigated the associations between two major dietary patterns and several risk factors for CVD. In longitudinal analyses with repeated measurements, using multivariate mixed linear regression models, the traditional dietary pattern (characterised by high consumption of rye, potatoes, butter, sausages, milk and coffee) was independently associated with total and LDL cholesterol concentrations, apolipoprotein B and C-reactive protein concentrations among both genders, and also with systolic blood pressure and insulin levels among women and concentrations of homocysteine among men (P < 0.05 for all). A dietary pattern reflecting more health-conscious food choices (such as high consumption of vegetables, legumes and nuts, tea, rye, cheese and other dairy products, and alcoholic beverages) was inversely, but less strongly associated with cardiovascular risk factors. Our results support earlier findings that dietary patterns have a role in the development of CVD.

Consistent dietary patterns identified from childhood to adulthood: the cardiovascular risk in Young Finns Study

Dietary patterns are useful in nutritional epidemiology, providing a comprehensive alternative to the traditional approach based on single nutrients. The Cardiovascular Risk in Young Finns Study is a prospective cohort study with a 21-year follow-up. At baseline, detailed quantitative information on subjects' food consumption was obtained using a 48 h dietary recall method (n 1768, aged 3-18 years). The interviews were repeated after 6 and 21 years (n 1200 and n 1037, respectively). We conducted a principal component analysis to identify major dietary patterns at each study point. A set of two similar patterns was recognised throughout the study. Pattern 1 was positively correlated with consumption of traditional Finnish foods, such as rye, potatoes, milk, butter, sausages and coffee, and negatively correlated with fruit, berries and dairy products other than milk. Pattern 1 type of diet was more common among male subjects, smokers and those living in rural areas. Pattern 2, predominant among female subjects, non-smokers and in urban areas, was characterised by more health-conscious food choices such as vegetables, legumes and nuts, tea, rye, cheese and other dairy products, and also by consumption of alcoholic beverages. Tracking of the pattern scores was observed, particularly among subjects who were adolescents at baseline. Of those originally belonging to the uppermost quintile of pattern 1 and 2 scores, 41 and 38 % respectively, persisted in the same quintile 21 years later. Our results suggest that food behaviour and concrete food choices are established already in childhood or adolescence and may significantly track into adulthood.