Improving food frequency questionnaires: a qualitative approach using cognitive interviewing

Considerations for a protein-focused screening instrument in clinical nutrition assessment

Physiological stress during injury and surgery negatively impacts protein balance and muscle mass maintenance. Adequate perioperative protein intake may attenuate muscle atrophy to maintain and facilitate functional recovery, particularly in older adults; yet, screening tools routinely used in clinical settings do not specifically assess protein intake when assessing nutrition risk. Although assessing malnutrition is a priority, suboptimal protein intake in non-malnourished patients should also be identified given protein's critical role in muscle health. This opinion paper highlights the potential for using a clinically appropriate protein-focused screener for rapid and efficient characterization of protein intake.

Prevalence of Undiagnosed Iron Deficiency Anemia and Associated Factors Among Female Undergraduate Medical Students in Makkah, Saudi Arabia

INTRODUCTION

Iron deficiency anemia is the most common type of anemia according to the World Health Organization. Females are more likely to be affected than males. There are several factors causing iron deficiency anemia, such as increased loss of iron, decreased intake of iron, and increased utilization of iron. There are limited research studies evaluating the risk factors that cause anemia among female medical students in Saudi Arabia. For this, the study aimed to identify the prevalence of undiagnosed iron deficiency anemia (IDA) among young female university students and to identify if there is any correlation between IDA and several factors including dietary habits, psychological stress, anxiety status, and body mass index.

MATERIALS AND METHODS

A cross-sectional observational study was performed between October 2022 and December 2022 with a sample of 100 healthy female students aged between 19 and 23 years, who were studying at the medical colleges of Umm Al-Qura University, Saudi Arabia. Blood samples were collected to perform complete blood count and iron profile tests. Also, a survey was done to find correlation between iron deficiency anemia and dietary intake, drinks, stress, anxiety, and body mass index (BMI). Independent t-test or Mann-Whitney U test were used to compare values for non-anemic with anemic participants, and linear regression tests were used to analyze differences between non-anemic and anemic participants' dietary intake factors and stress and anxiety scores. The level of significance was set at p<0.05.

RESULTS

The findings represent an overall prevalence of iron deficiency anemia in female medical students based on the lab finding results. Thus, students were divided into two following groups: anemic (13%) with hemoglobin (Hb) concentration <12 g/dL and non-anemic (84%) with Hb concentration ≥12 g/dL. When comparing the two groups, results showed significant differences in the majority of RBC indices (hematocrit {HCT}, mean corpuscular volume {MCV}, mean corpuscular hemoglobin {MCH}, red cell distribution width {RDW}) and iron profiles, p-value was <0.05. On evaluation of the different types of food consumption, the mean iron intake was around 7 mg/day, and in 65% of the participants, it was below the estimated average requirement (EAR) of iron (8.1 mg/dL). The perceived stress scale (PSS) shows that 63% of the participants experienced moderate stress and 58% reported severe anxiety by the generalized anxiety disorder (GAD) scale. In multiple linear regression, iron was positively associated with hemoglobin concentrations, whereas stress scores were negatively associated with hemoglobin concentrations.

CONCLUSION

There is a relatively low prevalence of anemia and most of it was found of the microcytic type, indicating that this condition is a common health issue among local female college students. There was no independent association between stress or anxiety and hemoglobin levels.

Validity and reproducibility of a food frequency questionnaire for breast cancer survivors in Korea

BACKGROUND/OBJECTIVES

The aim of this study was to examine the validity and reproducibility of a food frequency questionnaire (FFQ) developed in Korea for breast cancer survivors.

SUBJECTS/METHODS

Ninety-nine breast cancer survivors who completed an FFQ twice and three 3-day dietary records (DRs) between 2016-2017 were included. Energy and 14 nutrient intakes were calculated from FFQs and DRs. To determine the validity of the FFQ, energy-adjusted de-attenuated Pearson correlations between two FFQ assessments and the average of the three 3-day DRs were calculated, and to determine reproducibility, energy-adjusted Pearson correlations and degrees of agreement were calculated between the first and second FFQ assessments.

RESULTS

Correlation coefficients of validity ranged from 0.29 (protein) to 0.47 (fat) (median value = 0.36) for the FFQ assessment and from 0.20 (riboflavin) to 0.53 (calcium) (median value = 0.37) for the second. Correlation coefficients of reproducibility ranged from 0.22 (sodium) to 0.62 (carbohydrate) (median value = 0.36). Regarding FFQ reproducibilities, percentage classifications of exact agreements for energy-adjusted nutrients ranged from 27.3% (sodium) and 45.5% (fat). A median 76.8% of participants were classified into the same or adjacent quartiles, while a median of 5.6% of participants were classified in extreme quartiles. Bland-Atman plots for the majority of data points of three macronutrients, calcium and vitamins A and C fell within limits of agreement.

CONCLUSIONS

These results indicated that the newly developed FFQ for Korean breast cancer survivors has acceptable validity and reproducibility as compared with three 3-day DRs collected over a one-year period.

Adherence to 5 Diet Quality Indices and Pancreatic Cancer Risk in a Large US Prospective Cohort

Few prospective studies have examined associations between diet quality and pancreatic ductal adenocarcinoma (PDAC), or comprehensively compared diet quality indices. We conducted a prospective analysis of adherence to the Healthy Eating Index (HEI)-2015, alternative HEI-2010, alternate Mediterranean diet (aMed), and 2 versions of Dietary Approaches to Stop Hypertension (DASH; Fung and Mellen) and PDAC within the National Institutes of Health (NIH)-AARP Diet and Health Study (United States, 1995-2011). The dietary quality indices were calculated using responses from a 124-item food frequency questionnaire completed by 535,824 participants (315,780 men and 220,044 women). We used Cox proportional hazards regression models to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for each diet quality index and PDAC. During follow-up through 2011 (15.5-year median), 3,137 incident PDAC cases were identified. Compared with those with the lowest adherence quintile, participants with the highest adherence to the HEI-2015 (HR = 0.84, 95% CI: 0.75, 0.94), aMed (HR = 0.82, 95% CI: 0.73, 0.93), DASH-Fung (HR = 0.85, 95% CI: 0.77, 0.95), and DASH-Mellen (HR = 0.86, 95% CI: 0.77, 0.96) had a statistically significant, lower PDAC risk; this was not found for the alternative HEI-2010 (HR = 0.93, 95% CI: 0.83, 1.04). This prospective observational study supports the hypothesis that greater adherence to the HEI-2015, aMed, and DASH dietary recommendations may reduce PDAC.

Valuing the Diversity of Research Methods to Advance Nutrition Science

The ASN Board of Directors appointed the Nutrition Research Task Force to develop a report on scientific methods used in nutrition science to advance discovery, interpretation, and application of knowledge in the field. The genesis of this report was growing concern about the tone of discourse among nutrition professionals and the implications of acrimony on the productive study and translation of nutrition science. Too often, honest differences of opinion are cast as conflicts instead of areas of needed collaboration. Recognition of the value (and limitations) of contributions from well-executed nutrition science derived from the various approaches used in the discipline, as well as appreciation of how their layering will yield the strongest evidence base, will provide a basis for greater productivity and impact. Greater collaborative efforts within the field of nutrition science will require an understanding that each method or approach has a place and function that should be valued and used together to create the nutrition evidence base. Precision nutrition was identified as an important emerging nutrition topic by the preponderance of task force members, and this theme was adopted for the report because it lent itself to integration of many approaches in nutrition science. Although the primary audience for this report is nutrition researchers and other nutrition professionals, a secondary aim is to develop a document useful for the various audiences that translate nutrition research, including journalists, clinicians, and policymakers. The intent is to promote accurate, transparent, verifiable evidence-based communication about nutrition science. This will facilitate reasoned interpretation and application of emerging findings and, thereby, improve understanding and trust in nutrition science and appropriate characterization, development, and adoption of recommendations.

Healthy Eating Score-7 as a Measure of Diet Quality in a Military Population

OBJECTIVE

Identify potential revisions to the Healthy Eating Score (HES-5) that improve associations with the Healthy Eating Index (HEI) -2015 total and component scores.

METHODS

Pearson r correlations were determined from soldiers' (n = 433) survey data, including the HES, proposed additional questions, and the Block Food Frequency Questionnaire.

RESULTS

Adding sugar-sweetened beverages and energy drink questions (HES-7) strengthened the HES and HEI-2015 correlation (HES-5; r = 0.42, n = 433, r² = 0.18, P < 0.001) (HES-7; r = 0.52, r² = 0.27, P < 0.001). The HES components and Block Food Frequency Questionnaire consumption correlations were as follows: quantity of fruit (r = 0.37, r² = 0.14, P < 0.001), vegetables (r = 0.41, r² = 0.17, P < 0.001), whole grains (r = 0.35, r² = 0.12 P < 0.001), dairy (r = 0.34, r² = 0.12, P < 0.001), fish (r = 0.31, r² = 0.10, P < 0.001), and energy drink (r = 0.59, r² = 0.35, P < 0.001).

CONCLUSIONS AND IMPLICATIONS

HES-7 had the strongest correlation with HEI-2015. Future studies can explore if including consumption quantity in the HES improves its representation of diet quality.

An investigation of cross-sectional associations of a priori-selected dietary components with circulating bile acids

BACKGROUND

A growing body of literature suggests chronically higher bile acid (BA) concentrations may be associated with multiple health conditions. Diet may affect BA metabolism and signaling; however, evidence from human populations is lacking.

OBJECTIVES

We systematically investigated cross-sectional associations of a priori-selected dietary components (fiber, alcohol, coffee, fat) with circulating BA concentrations.

METHODS

We used targeted, quantitative LC-MS/MS panels to measure 15 circulating BAs in a subset of the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC; n = 2224) and Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO; n = 986) comprising Finnish male smokers and United States men and women, respectively. We used multivariable linear regression to estimate associations of each dietary component with log-transformed BAs; exponentiated coefficients estimate proportional differences. We included the median of the dietary component quartile in linear regression models to test for trend.

RESULTS

In ATBC, fiber was inversely associated with multiple circulating BAs. The proportional difference was -10.09% (95% CI: -19.29 to 0.16; P-trend = 0.04) when comparing total BAs among those in the highest relative to the lowest fiber quartile. Alcohol, trans fat, and polyunsaturated fat were positively associated with BAs in ATBC. The proportional difference comparing total BAs among those in the highest relative to the lowest alcohol quartile was 8.76% (95% CI: -3.10 to 22.06; P-trend = 0.03). Coffee and monounsaturated fat were inversely associated with BAs. The proportional difference comparing total BAs among those in the highest relative to the lowest coffee quartile was -24.03% (95% CI: -31.57 to -15.66; P-trend < 0.0001). In PLCO, no dietary components were associated with BAs except fiber, which was inversely associated with tauroursodeoxycholic acid.

CONCLUSIONS

Alcohol, coffee, certain fat subtypes, and fiber were associated with circulating concentrations of multiple BAs among Finnish male smokers. Given the potential role of BAs in disease risk, further investigation of the effects of diet on BAs in humans is warranted.

Integrating Dietary Data into Microbiome Studies: A Step Forward for Nutri-Metaomics

Diet is recognised as the main driver of changes in gut microbiota. However, linking habitual dietary intake to microbiome composition and activity remains a challenge, leaving most microbiome studies with little or no dietary information. To fill this knowledge gap, we conducted two consecutive studies (n = 84: a first pilot study (n = 40) to build a web-based, semi-quantitative simplified FFQ (sFFQ) based on three 24-h dietary recalls (24HRs); a second study (n = 44) served to validate the newly developed sFFQ using three 24HRs as reference method and to relate gut microbiome profiling (16S rRNA gene) with the extracted dietary and lifestyle data. Relative validation analysis provided acceptable classification and agreement for 13 out of 24 (54%) food groups and 20 out of 29 nutrients (69%) based on intraclass correlation coefficient, cross-classification, Spearman's correlation, Wilcoxon test, and Bland-Altman. Microbiome analysis showed that higher diversity was positively associated with age, vaginal birth, and intake of fruit. In contrast, microbial diversity was negatively associated with BMI, processed meats, ready-to-eat meals, sodium, and saturated fat. Our analysis also revealed a correlation between food groups or nutrients and microbial composition. Overall, we provide the first dietary assessment tool to be validated and correlated with microbiome data for population studies.

Assessment of polyunsaturated fatty acids: A self-report and biomarker assessment with a racially and ethnically diverse sample of women

Polyunsaturated fatty acids (PUFAs) play an important role in human health, influencing chronic disease and mortality. Food Frequency Questionnaires (FFQs) are widely used to assess self-reported diet, but they can be subject to a variety of errors. Accordingly, an accurate assessment of diet is crucial in nutrition research. This study examined the association between a widely-used self-report measure of PUFAs (Diet History Questionnaire-II: DHQ-II) with the proportion of PUFA in red blood cell (RBC) membranes, and examined whether this relationship was moderated by race/ethnicity. In a racially and ethnically diverse sample of 132 female participants (M_age = 21.97±3.98, range 18 to 42 years), bivariate correlations and linear regression analyses demonstrated associations between DHQ-II and proportion of nutrients in RBCs for omega-3 fatty acids EPA (r = 0.39, ß = 0.38, p < .01), DHA (r = 0.48, ß = 0.47, p < .01), and EPA+DHA (r = 0.51, β = 0.49, p < .01). No associations were found for omega-3 fatty acid ALA or omega-6 fatty acids LA or ARA. DHQ-II and RBC associations for EPA, DHA, and EPA+DHA were moderated by race/ethnicity, controlling for age. Self-report of EPA was most consistent with RBC proportions for Caucasian individuals, and less consistent for Black/African American individuals. Self-reports of DHA and EPA+DHA were most consistent with RBC proportions for Caucasian individuals, and less consistent for Black/African American individuals and Hispanic/Latina individuals, although still statistically significant. No associations were detected for Hispanic/Latina individuals (for EPA only), Asian/Pacific Islanders or individuals of mixed/other descent. The present study found that when compared to PUFA biomarkers, the DHQ-II did not assess PUFAs consistently across all racial/ethnic groups in this sample of women. Further research is needed to determine what factors contribute to weak or lacking correlations between reported fat intake and corresponding values in RBCs, including but not limited to recall errors, underestimations of fatty acids in food composition databases, insufficient DHQ-II assessment of fatty acids in general and from particular cultures, and genetic differences in fat metabolism.

Providing Comprehensive Dietary Fatty Acid Profiling from Saturates to Polyunsaturates with the Malaysia Lipid Study-Food Frequency Questionnaire: Validation Using the Triads Approach

To address limited food frequency questionnaire (FFQ) capacity in public health monitoring in Malaysia, we aimed to develop a semi-quantitative FFQ for an adult multiethnic population for comprehensive fatty acid (FA) profiling inclusive of saturated (SFA), monounsaturated (MUFA), polyunsaturated fatty acids (PUFA), PUFA:SFA ratio, trans fatty acids, omega-3 and omega-6 FAs. A 240-food itemed FFQ used diet records (DR) of Malaysia Lipid Study (MLS) participants and fatty acid composition database from laboratory analyzed foods. The developed MLS-FFQ underwent face and content validation before relative validation in a free-living population (n = 114). Validation was facilitated for macronutrient data comparisons between DR and FFQ via Spearman’s correlation coefficient analyses; and for fatty acid composition data by independent pairing of DR, FFQ and plasma triglyceride using the triads method. Moderate correlation between dietary methods was obtained for macronutrients and FAs (r = 0.225–0.457, p < 0.05) except for ω-3 FAs, presenting good agreement with grossly misclassified nutrients <10%. For fatty acid composition data, the magnitude of validity coefficients (z) for SFA, PUFA, PUFA:SFA ratios and ω-6 FAs by all 3 methods were not significantly different (p > 0.05). In conclusion, the MLS-FFQ was shown to be a valid tool to assess population dietary intakes.

Does Incorporating Gender Differences into Quantifying a Food Frequency Questionnaire Influence the Association of Total Energy Intake with All-Cause and Cause-Specific Mortality?

This study aims to evaluate whether incorporating gender differences in portion sizes as part of quantifying a food frequency questionnaire influences the association of total energy intake with mortality. The analysis included 156,434 participants (70,142 men and 86,292 women) in the Multiethnic Cohort Study, aged 45-75 years at baseline. A total of 49,728 deaths were identified during an average follow-up of 18.1 years. Total energy intake and percentage energy from macronutrients were calculated using original portion sizes (PSs) and gender specific (GS)-PS and were divided into quintiles for men and women. The associations of total energy intake and percentage energy from macronutrients with all-cause, cardiovascular disease (CVD), and cancer mortality were examined using Cox regression with adjustment for potential confounders. Mean ± standard deviation daily total energy intake using original-PS was 2449 ± 1135 kcal for men and 1979 ± 962 kcal for women; using GS-PS was 1996 ± 884 kcal for men and 1595 ± 731 kcal for women. For men, the hazard ratios (HRs) (95% confidence intervals) for all-cause, CVD, and cancer comparing the highest to the lowest quintile of total energy intake were 1.05 (1.00-1.10), 1.07 (0.99-1.16), 1.03 (0.95-1.13) using original-PS and 1.07 (1.02-1.12), 1.11 (1.03-1.20), 1.02 (0.94-1.12) using GS-PS, respectively. For women, the corresponding HRs were 1.03 (0.98-1.09), 0.99 (0.91-1.08), 1.10 (1.00-1.21) using original-PS and 1.06 (1.01-1.12), 1.02 (0.94-1.12), 1.07 (0.97-1.18) using GS-PS. Both versions of percentage energy from total fat were associated with an increased risk of all-cause, CVD, and cancer mortality; on the other hand, both versions of percentage energy from carbohydrate showed inverse associations with all-cause, CVD, and cancer mortality in both men and women. When using original-PS and GS-PS, the estimated total energy intake differed, resulting in marginal differences in the associations of total energy intake with all-cause, CVD, and cancer mortality.

Development and validation of a quantitative food frequency questionnaire to assess dietary intake among Lebanese adults

BACKGROUND

The food frequency questionnaire (FFQ) is the most frequently used method to assess dietary intake in epidemiological studies evaluating diet-disease association. The objective of this study was to validate a FFQ for use among Lebanese adults by evaluating various facets of validity and reproducibility.

METHODS

The quantitative 164-items FFQ was validated against the average of six 24-h dietary recalls (DRs) in a sample of 238 Lebanese adults. Reproducibility of the FFQ was assessed by administering it twice within 1 month' time interval.

RESULTS

Positive statistically significant Pearson correlations were observed in most macro and micronutrients between the FFQ and the six 24-h DRs, ranging from 0.16 to 0.65, with two thirds of the correlation coefficients exceeding 0.3. Energy, gender, and age-adjusted statistically significant Pearson correlation coefficients ranged from 0.14 to 0.64, with two thirds of the coefficients exceeding 0.2. Intakes from the FFQ were mostly higher than those of the 24-h DRs. Mean percent difference between nutrient intakes from both dietary methods decreased remarkably after using energy-adjusted mean intakes. Values were acceptable to good for all macronutrients and several micronutrients. Cross-classification analysis revealed that around 64.3 to 83.9% of participants were classified into the same and adjacent quartile whereas grossly misclassified proportions ranged from 3.7 to 12.2%. Weighted kappa values ranged from 0.02 to 0.36 with most of them exceeding 0.2. In indirect validity analysis, key nutrient mean intakes estimated from the six 24-h DRs were significantly positively associated with tertiles of food groups derived from the FFQ. Bland Altman plots showed that the majority of data points fell within the limits of agreement (LOA) for all nutrients. As for reproducibility analysis, ICC values were all statistically significant ranging from 0.645 to 0.959 and Bland Altman plots confirmed these results.

CONCLUSIONS

Based on various aspects of validity and reproducibility, and an extensive range of statistical tests, the present FFQ developed for a Lebanese community is an acceptable tool for dietary assessment and is useful for evaluating diet-disease associations in future studies.

Improving the Reporting of Young Children's Food Intake: Insights from a Cognitive Interviewing Study with Mothers of 3-7-Year Old Children

Short food questions (SFQ) allow for rapid reporting of food intake across a variety of settings but are limited by poor validity and reliability. Understanding the recall process used by parents to report children’s food intake can improve question design and psychometric performance. This study aimed to improve understanding of how parents report children’s dietary intake using SFQ. Semi-structured, cognitive interviews were conducted with 21 mothers of 3–7-year-old children. Mothers were asked to ‘think-aloud’ while answering SFQ about their child’s food intake. Thematic analysis identified themes relating to parent’s question and answer process and barriers to recall. Information retrieval strategies focused on ‘use-of-time’ and ‘sphere of food provision’ and differed for core versus unhealthy foods. Recall of routine and home food provision were used to report core food intake, whereas recall of special occasions and food provision outside the home guided recall of discretionary foods. Mothers utilize different recall strategies for core and discretionary foods based on use of time and the sphere of food provision. The ease of reporting children’s dietary intake may be improved by utilizing a shorter recall time frame, clear and direct question wording, and use of food examples and recall prompts.

Ratios of Food Amounts across Three Portion Size Categories on a Food Frequency Questionnaire in Men and Women

BACKGROUND

For some quantitative food frequency questionnaire (QFFQ) items, data may be insufficient to set gram weights for multiple portion size (PS) categories. Ratios of food amounts across PS categories may be used to quantify these PS for less frequently consumed food items.

OBJECTIVE

To explore the ratios of food amounts reported in 24-hour dietary recalls (24HDRs) by a sample of participants in a cohort study who chose the A (smallest) or C (largest) PS category on the QFFQ, relative to the food amounts for those who chose the B PS category.

DESIGN

This study was conducted as a cross-sectional design.

PARTICIPANTS/SETTING

Data were from participants (n=2,360) who completed three 24HDRs and the QFFQ in a calibration study of the Multiethnic Cohort Study in 1994-1997.

MAIN OUTCOME MEASURES

Median food amounts were calculated from 24HDRs for participants who selected each PS category (A, smallest; B; and C, largest) of items on the QFFQ. A-to-B and C-to-B ratios were computed if reported by five or more people in the 24HDRs: A-to-B ratios for 68 items (men) and 88 items (women); C-to-B ratios for 93 items (men) and 79 items (women).

STATISTICAL ANALYSES PERFORMED

The t test was used to compare the mean A-to-B ratios and C-to-B ratios as preset on the QFFQ with those from the 24HDRs and to examine sex differences. Analysis of variance was used to compare the mean ratios among race and ethnicity groups.

RESULTS

Mean A-to-B and C-to-B ratios were 0.71±0.15 and 1.45±0.35 in men and 0.71±0.15 and 1.44±0.40 in women based on the 24HDRs. Compared with the original QFFQ PS (A-to-B ratio=0.5±0.07; C-to-B ratio=1.8±0.30), the ratios were closer to 1 both in men and women (P<0.001). There were no significant sex differences or racial or ethnic differences.

CONCLUSIONS

These results provide guidance on appropriate ratios to use to set values for small and large PS categories on a QFFQ, particularly for items with insufficient information on usual PS.

Organizational characteristics associated with high performance on quality measures in pediatric primary care: A positive deviance study

BACKGROUND

Pediatric health care quality in the United States varies, but the reasons for variation are not fully understood. Differences in pediatric practices' organizational characteristics, such as organizational structures, strategies employed to improve quality, and other contextual factors, may contribute to the variation observed.

PURPOSE

To assess the relationship between organizational characteristics and performance on clinical quality (CQ) and patient experience (PE) measures in primary care pediatric practices in Massachusetts.

METHODOLOGY

A 60-item questionnaire that assessed the presence of selected organizational characteristics was sent to 172 pediatric practice managers in Massachusetts between December 2017 and February 2018. The associations between select organizational characteristics and publicly available CQ and PE scores were analyzed using analysis of variance; open-ended survey questions were analyzed using qualitative content analysis.

RESULTS

Eighty-six practices (50.0%) responded; 80 (46.5%) were included in the primary analysis. Having a quality champion ( p = .03), offering co-located specialty services (e.g., behavioral health; p = .04), being a privately owned practice ( p = .04), believing that patients and families feel respected ( p = .03), and having a lower percentage of patients (10%-25%) covered by public health insurance ( p = .04) were associated with higher CQ scores. Higher PE scores were associated with private practice ownership ( p = .0006). Qualitative analysis suggested organizational culture and external factors, such as health care finance, may affect quality.

CONCLUSIONS

Both modifiable organizational practices and factors external to a practice may affect quality of care. Addressing differences in practice performance may not be reducible to implementation of changes in single organizational characteristics.

PRACTICE IMPLICATIONS

Pediatric practices seeking to improve quality of care may wish to adopt the strategies that were associated with higher performance on quality measures, but additional studies are needed to better understand the mechanisms behind these associations and how they relate to each other.

Dietary Intake and Physical Activity Assessment: Current Tools, Techniques, and Technologies for Use in Adult Populations

Accurate assessment of dietary intake and physical activity is a vital component for quality research in public health, nutrition, and exercise science. However, accurate and consistent methodology for the assessment of these components remains a major challenge. Classic methods use self-report to capture dietary intake and physical activity in healthy adult populations. However, these tools, such as questionnaires or food and activity records and recalls, have been shown to underestimate energy intake and expenditure as compared with direct measures like doubly labeled water. This paper summarizes recent technological advancements, such as remote sensing devices, digital photography, and multisensor devices, which have the potential to improve the assessment of dietary intake and physical activity in free-living adults. This review will provide researchers with emerging evidence in support of these technologies, as well as a quick reference for selecting the "right-sized" assessment method based on study design, target population, outcome variables of interest, and economic and time considerations.

THEME INFORMATION

This article is part of a theme issue entitled Innovative Tools for Assessing Diet and Physical Activity for Health Promotion, which is sponsored by the North American branch of the International Life Sciences Institute.

Development of a tool to measure the number of foods and beverages consumed by children using National Health and Nutrition Examination Survey (NHANES) FFQ data

Objective

There is currently no standard, objective definition of selective eating. This is partially because normative values for the number of different foods eaten by US children have not been established. The present study objectives were to: (i) perform exploratory analysis on the number of different foods, beverages, and total foods and beverages consumed by US children aged 2–18 years over a year’s time, and the types of foods consumed by those in the lowest 2·5th percentile; and (ii) determine whether those values differ according to demographic variables and weight status.

Design

Secondary analysis of cross-sectional FFQ data. Differences in number of foods, beverages, and total foods and beverages were analysed using one-way ANOVA.

Setting

National Health and Nutrition Examination Survey (NHANES) for the years 2003–2006.

Subjects

Non-institutionalized US children aged 2–18 years.

Results

The mean number of different foods and beverages consumed across the sample was 83·2. There were no significant differences by gender, BMI, race or food security categories. There was a difference in beverage consumption by age category, with children aged 12–18 years consuming a significantly higher number of different beverages compared with each of the other two age categories (i.e. 2–5 years and 6–11 years).

Conclusions

Normative values for the number of foods and drinks reported as consumed by children over the past 12 months may be a useful measure for researchers. Future research validating this measure is needed before cut-off values can be used to develop a definition of selective eating.

The impact of folate intake on the risk of head and neck cancer in the prostate, lung, colorectal, and ovarian cancer screening trial (PLCO) cohort

BACKGROUND

Although low levels of folate leads to disturbances in DNA replication, DNA methylation and DNA repair, the association between dietary folate intake and head and neck cancer (HNC) risk remains unclear.

METHODS

We evaluated the association between folate intake and HNC risk using prospective cohort data from the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial. This study included 101 700 participants and 186 cases with confirmed incident HNC. The median follow-up was 12.5 years. We estimated hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) using Cox proportional hazard model including age, sex, body mass index, education, race, tobacco smoking, alcohol drinking and total fruit and vegetable intake.

RESULTS

Higher intake of food folate and fortified folic acid in foods was associated with a decreasing HNC risk in a dose-response manner. The HRs of highest vs the lowest quartile of intake were 0.35 (95%CI: 0.18-0.67) for food folate, and 0.49 (95%CI: 0.30-0.82) for fortified folic acid. Intakes of total folate, natural folate and supplemental folic acid were not associated with the risk of HNC and its subsites. We did not detect any interaction between smoking, drinking and food folate intake on HNC risk.

CONCLUSIONS

These findings provide evidence of the protective role of dietary folate intake on HNC risk.

Using item response theory to address vulnerabilities in FFQ

The limitations for self-reporting of dietary patterns are widely recognised as a major vulnerability of FFQ and the dietary screeners/scales derived from FFQ. Such instruments can yield inconsistent results to produce questionable interpretations. The present article discusses the value of psychometric approaches and standards in addressing these drawbacks for instruments used to estimate dietary habits and nutrient intake. We argue that a FFQ or screener that treats diet as a 'latent construct' can be optimised for both internal consistency and the value of the research results. Latent constructs, a foundation for item response theory (IRT)-based scales (e.g. Patient Reported Outcomes Measurement Information System) are typically introduced in the design stage of an instrument to elicit critical factors that cannot be observed or measured directly. We propose an iterative approach that uses such modelling to refine FFQ and similar instruments. To that end, we illustrate the benefits of psychometric modelling by using items and data from a sample of 12 370 Soldiers who completed the 2012 US Army Global Assessment Tool (GAT). We used factor analysis to build the scale incorporating five out of eleven survey items. An IRT-driven assessment of response category properties indicates likely problems in the ordering or wording of several response categories. Group comparisons, examined with differential item functioning (DIF), provided evidence of scale validity across each Army sub-population (sex, service component and officer status). Such an approach holds promise for future FFQ.

Perspective: An Extension of the STROBE Statement for Observational Studies in Nutritional Epidemiology (STROBE-nut): Explanation and Elaboration

Nutritional epidemiology is an inherently complex and multifaceted research area. Dietary intake is a complex exposure and is challenging to describe and assess, and links between diet, health, and disease are difficult to ascertain. Consequently, adequate reporting is necessary to facilitate comprehension, interpretation, and generalizability of results and conclusions. The STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) statement is an international and collaborative initiative aiming to enhance the quality of reporting of observational studies. We previously presented a checklist of 24 reporting recommendations for the field of nutritional epidemiology, called "the STROBE-nut." The STROBE-nut is an extension of the general STROBE statement, intended to complement the STROBE recommendations to improve and standardize the reporting in nutritional epidemiology. The aim of the present article is to explain the rationale for, and elaborate on, the STROBE-nut recommendations to enhance the clarity and to facilitate the understanding of the guidelines. Examples from the published literature are used as illustrations, and references are provided for further reading.

Nutritional metabolomics and breast cancer risk in a prospective study

Background: The epidemiologic evidence for associations between dietary factors and breast cancer is weak and etiologic mechanisms are often unclear. Exploring the role of dietary biomarkers with metabolomics can potentially facilitate objective dietary characterization, mitigate errors related to self-reported diet, agnostically test metabolic pathways, and identify mechanistic mediators.Objective: The aim of this study was to evaluate associations of diet-related metabolites with the risk of breast cancer in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.Design: We examined prediagnostic serum concentrations of diet-related metabolites in a nested case-control study in 621 postmenopausal invasive breast cancer cases and 621 matched controls in the multicenter PLCO cohort. We calculated partial Pearson correlations between 617 metabolites and 55 foods, food groups, and vitamin supplements on the basis of the 2015 Dietary Guidelines for Americans and derived from a 137-item self-administered food-frequency questionnaire. Diet-related metabolites (P-correlation < 1.47 × 10^-6) were evaluated in breast cancer analyses. ORs for the 90th compared with the 10th percentile were calculated by using conditional logistic regression, with body mass index, physical inactivity, other breast cancer risk factors, and caloric intake controlled for (false discovery rate <0.2).Results: Of 113 diet-related metabolites, 3 were associated with overall breast cancer risk (621 cases): caprate (10:0), a saturated fatty acid (OR: 1.77; 95% CI = 1.28, 2.43); γ-carboxyethyl hydrochroman (γ-CEHC), a vitamin E (γ-tocopherol) derivative (OR: 1.64; 95% CI: 1.18, 2.28); and 4-androsten-3β,17β-diol-monosulfate (1), an androgen (OR: 1.61; 95% CI: 1.20, 2.16). Nineteen metabolites were significantly associated with estrogen receptor (ER)-positive (ER⁺) breast cancer (418 cases): 12 alcohol-associated metabolites, including 7 androgens and α-hydroxyisovalerate (OR: 2.23; 95% CI: 1.50, 3.32); 3 vitamin E (tocopherol) derivatives (e.g., γ-CEHC; OR: 1.80; 95% CI: 1.20, 2.70); butter-associated caprate (10:0) (OR: 1.81; 95% CI: 1.23, 2.67); and fried food-associated 2-hydroxyoctanoate (OR: 1.46; 95% CI: 1.03, 2.07). No metabolites were significantly associated with ER-negative breast cancer (144 cases).Conclusions: Prediagnostic serum concentrations of metabolites related to alcohol, vitamin E, and animal fats were moderately strongly associated with ER⁺ breast cancer risk. Our findings show how nutritional metabolomics might identify diet-related exposures that modulate cancer risk. This trial was registered at clinicaltrials.gov as NCT00339495.

Refinement of measures to assess psychosocial constructs associated with skin cancer risk and protective behaviors of young adults

The study's purpose was to select/refine measures assessing psychosocial constructs associated with skin cancer risk/protective behaviors. Cognitive interviewing was conducted with twenty participants locally, and a survey was conducted with 965 adults aged 18-25 years at moderate to high risk of developing skin cancer, recruited nationally online. Psychosocial measures assessed variables from the Integrative Model of Behavior Prediction. As a result of expert review and cognitive interviewing, items were removed, added, and/or made simpler, more personal, consistent, and less ambiguous. A factor analysis resulted in 14 scales and adequate model fit. Internal reliability and test-retest reliability was acceptable to good. Correlations among the psychosocial and behavioral variables were generally significant and in expected directions, demonstrating convergent validity. We have refined measures that assess important psychosocial constructs associated with skin cancer-related behaviors, that research participants can understand and complete successfully, and that are reliable and demonstrate evidence for validity.

Development and evaluation of a Nutrition Transition-FFQ for adolescents in South India

OBJECTIVE

To develop and evaluate a Nutrition Transition-FFQ (NT-FFQ) to measure nutrition transition among adolescents in South India.

DESIGN

We developed an interviewer-administered NT-FFQ comprising a 125-item semi-quantitative FFQ and a twenty-seven-item eating behaviour survey. The reproducibility and validity of the NT-FFQ were assessed using Spearman correlations, intra-class correlation coefficients (ICC), and levels of agreement using Bland-Altman and cross-classification over 2 months (NT-FFQ1 and NT-FFQ2). Validity of foods was evaluated against three 24-h dietary recalls (24-HR). Face validity of eating behaviours was evaluated through semi-structured cognitive interviews. The reproducibility of eating behaviours was assessed using weighted kappa (κ w) and cross-classification analyses.

SETTING

Vijayapura, India.

SUBJECTS

A representative sample of 198 adolescents aged 14-18 years.

RESULTS

Reproducibility of NT-FFQ: Spearman correlations ranged from 0·33 (pulses) to 0·80 (red meat) and ICC from 0·05 (fruits) to 1·00 (tea). On average, concordance (agreement) was 60 % and discordance was 7 % for food groups. For eating behaviours, κ w ranged from 0·24 (eating snacks while watching television) to 0·67 (eating lunch at home) with a mean of 0·40. Validity of NT-FFQ: Spearman correlations ranged from 0·11 (fried traditional foods) to 0·70 (tea) and ICC ranged from 0·02 (healthy global foods) to 1·00 (grains). The concordance and discordance were 48 % and 8 %, respectively. Bland-Altman plots showed acceptable agreement between NT-FFQ2 and 24-HR. The eating behaviours had acceptable face validity.

CONCLUSIONS

The NT-FFQ has good reproducibility and acceptable validity for food intake and eating behaviours. The NT-FFQ can quantify the nutrition transition among Indian adolescents.

Development of a FFQ for breast cancer survivors in Korea

Diet may play an important role in breast cancer recurrence or survival, and therefore assessment of long-term diet among breast cancer survivors is important in breast cancer survivorship research. Given that the diet of breast cancer survivors may differ from that of the general population, the use of a FFQ specific to this group may be needed. The objective of this study was to develop a FFQ for breast cancer survivors, the most commonly used tool to measure long-term dietary patterns in nutritional epidemiological studies. We collected information on the foods and amounts of foods consumed using 3-d dietary records from a total of 192 women who had been diagnosed with stage I–III breast cancers and had undergone breast cancer surgery at least 6 months before the baseline study. A total of 1254 foods and dishes consumed were re-grouped by the similarity of the main ingredients and/or serving units, and several dishes commonly consumed among the Korean population were added. After we performed contribution analyses and variability analyses to detect between-person variation for selected nutrients, we listed a total of 123 foods and dishes for the FFQ specific to breast cancer survivors. Our breast cancer survivor-specific FFQ can be used to estimate long-term dietary intake and to examine its association with breast cancer prognosis in epidemiological studies of breast cancer in Korea.

Development of a Semi-Quantitative Food Frequency Questionnaire to Assess the Dietary Intake of a Multi-Ethnic Urban Asian Population

Assessing habitual food consumption is challenging in multi-ethnic cosmopolitan settings. We systematically developed a semi-quantitative food frequency questionnaire (FFQ) in a multi-ethnic population in Singapore, using data from two 24-h dietary recalls from a nationally representative sample of 805 Singapore residents of Chinese, Malay and Indian ethnicity aged 18–79 years. Key steps included combining reported items on 24-h recalls into standardized food groups, developing a food list for the FFQ, pilot testing of different question formats, and cognitive interviews. Percentage contribution analysis and stepwise regression analysis were used to identify foods contributing cumulatively ≥90% to intakes and individually ≥1% to intake variance of key nutrients, for the total study population and for each ethnic group separately. Differences between ethnic groups were observed in proportions of consumers of certain foods (e.g., lentil stews, 1%–47%; and pork dishes, 0%–50%). The number of foods needed to explain variability in nutrient intakes differed substantially by ethnic groups and was substantially larger for the total population than for separate ethnic groups. A 163-item FFQ covered >95% of total population intake for all key nutrients. The methodological insights provided in this paper may be useful in developing similar FFQs in other multi-ethnic settings.

Comparison of approaches to correct intake–health associations for FFQ measurement error using a duplicate recovery biomarker and a duplicate 24 h dietary recall as reference method

OBJECTIVE

To illustrate the impact of intake-related bias in FFQ and 24 h recall (24hR), and correlated errors between these methods, on intake-health associations.

DESIGN

Dietary intake was assessed by a 180-item semi-quantitative FFQ and two 24hR. Urinary N and urinary K were estimated from two 24 h urine samples. We compared four scenarios to correct associations for errors in an FFQ estimating protein and K intakes.

SETTING

Wageningen, The Netherlands.

SUBJECTS

Fifty-nine men and fifty-eight women aged 45–65 years.

RESULTS

For this FFQ, measurement error weakened a true relative risk of 2·0 to 1·4 for protein and 1·5 for K. As compared with calibration to duplicate recovery biomarkers (i.e. the preferred scenario 1), estimating a validity coefficient using this duplicate biomarker resulted in overcorrected associations, caused by intake-related bias in the FFQ (scenario 2). The correction factor based on a triad using biomarkers and 24hR was hampered by this intake-related bias and by correlated errors between FFQ and 24hR, and in this population resulted in a nearly perfect correction for protein but an overcorrection for K (scenario 3). When the 24hR was used for calibration, only a small correction was done, due to correlated errors between the methods and intake-related bias in the 24hR (scenario 4).

CONCLUSIONS

Calibration to a gold standard reference method is the preferred approach to correct intake-health associations for FFQ measurement error. If it is not possible to do so, using the 24hR as reference method only partly removes the errors, but may result in improved intake-health associations.

The systemic lupus erythematosus travel burden survey: baseline data among a South Carolina cohort

BACKGROUND

Many studies on the impact of systemic lupus erythematosus or lupus have identified patient travel costs as being problematic. We administered a survey that examined the impact of self-rated travel burden on lupus patients. The systemic lupus erythematosus travel burden survey included 41 patients enrolled in the systemic lupus erythematosus database project at the Medical University of South Carolina.

RESULTS

Most participants reported that travel caused medications to be discontinued or appointments to be missed. In unadjusted logistic regressions of the relationship between these outcomes and medical travel burden, both distance to rheumatologists and time to lupus medical care were significant.

CONCLUSIONS

Our findings suggest that more research is needed to examine the influence of travel burden among this population, but data from this report could help to inform physicians, academic researchers, and other health professionals in South Carolina and other areas with significant rural populations on how travel burden may impact patients receiving care for lupus and provide an opportunity for the development of interventions aimed at assisting lupus patients with management of stressors related to travel burden.

Evaluation of the Relative Validity of the Short Diet Questionnaire for Assessing Usual Consumption Frequencies of Selected Nutrients and Foods

A 36-item Short Diet Questionnaire (SDQ) was developed to assess usual consumption frequencies of foods providing fats, fibre, calcium, vitamin D, in addition to fruits and vegetables. It was pretested among 30 community-dwelling participants from the Québec Longitudinal Study on Nutrition and Successful Aging, “NuAge” (n = 1793, 52.4% women), recruited in three age groups (70 ± 2 years; 75 ± 2 years; 80 ± 2 years). Following revision, the SDQ was administered to 527 NuAge participants (55% female), distributed among the three age groups, both sexes and languages (French, English) prior to the second of three non-consecutive 24 h diet recalls (24HR) and validated relative to the mean of three 24HR. Full data were available for 396 participants. Most SDQ nutrients and fruit and vegetable servings were lower than 24HR estimates (p < 0.05) except calcium, vitamin D, and saturated and trans fats. Spearman correlations between the SDQ and 24HR were modest and significant (p < 0.01), ranging from 0.19 (cholesterol) to 0.45 (fruits and vegetables). Cross-classification into quartiles showed 33% of items were jointly classified into identical quartiles of the distribution, 73% into identical and contiguous quartiles, and only 7% were frankly misclassified. The SDQ is a reasonably accurate, rapid approach for ranking usual frequencies of selected nutrients and foods. Further testing is needed in a broader age range.

Considerations in selection of diet assessment methods for examining the effect of nutrition on cognition

Older adults are the most rapidly growing age group in the United States, and it is estimated that 22.2 % of U.S. adults over 71 years of age have cognitive impairments without dementia and 13.9% have dementia. Cognitive impairment is associated with reduced quality of life, increased risk of hospitalization, inability to live independently, and increased health care costs; therefore, identification of modifiable risk factors for prevention and delay of cognitive decline is of increasing importance. There is a growing body of research and interest in the relationship between diet and cognitive function. Epidemiologic studies suggest that cognitive function may be improved and cognitive decline prevented as a function of a particular nutrient, food group or dietary pattern; however, results from these trials have failed to be replicated in randomized controlled trials. One possible reason for the equivocality of findings in the diet and cognitive function literature may be the methodological issues and limitations in the assessment of dietary patterns and nutritional intake. Self-reported dietary data can be biased by many factors such as age, gender, socioeconomic status, and education; yet, there is limited research on the impact of cognitive function on the integrity of self-reported dietary data. Cognitive function itself may bias diet assessment methods, subsequently obscuring the evaluation of the nutrition-cognition relationship. The present review summarizes methodological validation studies that provide insight into potential errors of diet assessment methods due to cognitive function, identifies research gaps and provides recommendations for improving diet assessment accuracy in studies of individuals with cognitive impairments.

Evaluation of dietary patterns among Norwegian postmenopausal women using plasma carotenoids as biomarkers

A number of studies have examined dietary patterns in various populations. However, to study to what extent such patterns capture meaningful differences in consumption of foods is of interest. In the present study, we identified important dietary patterns in Norwegian postmenopausal women (age 50-69 years, n 361), and evaluated these patterns by examining their associations with plasma carotenoids. Diet was assessed by a 253-item FFQ. These 253 food items were categorised into forty-six food groups, and dietary patterns were identified using principal component analysis. We used the partial correlation coefficient (r(adj)) and multiple linear regression analysis to examine the associations between the dietary patterns and the plasma carotenoids α-carotene, β-carotene, β-cryptoxanthin, lutein, lycopene and zeaxanthin. Overall, four dietary patterns were identified: the 'Western'; 'Vegetarian'; 'Continental'; 'High-protein'. The 'Western' dietary pattern scores were significantly inversely correlated with plasma lutein, zeaxanthin, lycopene and total carotenoids (-0·25 ≤ r(adj) ≤ -0·13). The 'Vegetarian' dietary pattern scores were significantly positively correlated with all the plasma carotenoids (0·15 ≤ r(adj) ≤ 0·24). The 'Continental' dietary pattern scores were significantly inversely correlated with plasma lutein and α-carotene (r(adj) = -0·13). No significant association between the 'High-protein' dietary pattern scores and the plasma carotenoids was found. In conclusion, the healthy dietary pattern, the 'Vegetarian' pattern, is associated with a more favourable profile of the plasma carotenoids than our unhealthy dietary patterns, the 'Western' and 'Continental' patterns.

Mainstreaming nutrition metrics in household surveys--toward a multidisciplinary convergence of data systems

Since the 2008 food price crisis, food and nutrition security are back on the global development agenda, with particular emphasis on agricultural pathways toward improved nutrition. Parallel efforts are being promoted to improve the data and metrics for monitoring progress toward positive nutritional outcomes, especially for women and children. Despite the increased investment in tracking nutritional outcomes, these efforts are often made in silos, which create challenges for integrating nutritional data with other sectoral data, such as those related to agriculture. This paper proposes a minimum set of nutrition indicators to be included in nationally representative agricultural (and multitopic) household surveys. Building multisectoral convergence across existing surveys will allow us to better identify priority interventions and to monitor progress toward improved nutrition targets.

Pictogram-based method of visualizing dietary intake

BACKGROUND

Pictograms have been shown by many studies to be an effective way of conveying information. An easy-to-understand pictorial description is essential for communication of dietary intake in the computer era.

OBJECTIVES

We proposed a novel approach that represents textual descriptions of dietary intake into a pictorial representation with the concept of pictograms. The computational implementation in terms of a web-based tool was investigated on how well the pictograms carry their intended message.

METHODS

1) We investigated how well the pictograms are comprehended in terms of subjects' accuracy rate and response time. In the study (n = 90), pictorial variants with three types of food images (black-and-white sketch, colored sketch, and colored photograph) were tested. 2) We also investigated how well subjects were able to select the standard food size among various food portions with the use of the tool. A comparison was made against the current standard of an educational session taught by a registered dietitian. We recruited 86 university students who were asked to select a standard size out of five different size categories. Three types of shapes were used. The bowl is the container that is widely used in the participants' country. The pork strip was to represent foods with elliptical cross-section. The apple was used to represent a baseball-like size and shape.

RESULTS

Two pictograms with black-and-white food image were low of less than 50% in accuracy rate. The rest of the twenty-seven pictograms derived from portions of the nine foods were well understood with high accuracy rates (above 85%). Participants in using the tool without the dietitian's session was better than participants in the dietitian education session in selecting a standard portion size of an apple (p < 0.0001; p = 0.0009 after adjustment for gender and age). The rate of correct bowl and pork strip size estimates were similar between the two conditions (p > 0.05).

CONCLUSION

The development of pictograms could be used as a computational visual aid for comprehending and identifying dietary intake. Broader investigation is required for considering the effectiveness of the pictograms on recall, measurement, or estimation as well as for further evaluation in the clinical practice.

Dietary assessment methods in epidemiologic studies

Diet is a major lifestyle-related risk factor of various chronic diseases. Dietary intake can be assessed by subjective report and objective observation. Subjective assessment is possible using open-ended surveys such as dietary recalls or records, or using closed-ended surveys including food frequency questionnaires. Each method has inherent strengths and limitations. Continued efforts to improve the accuracy of dietary intake assessment and enhance its feasibility in epidemiological studies have been made. This article reviews common dietary assessment methods and their feasibility in epidemiological studies.

Evaluation of a validated food frequency questionnaire for self-defined vegans in the United States

This study aimed to develop and validate a de novo food frequency questionnaire for self-defined vegans in the United States. Diet histories from pilot samples of vegans and a modified ‘Block Method’ using seven selected nutrients of concern in vegan diet patterns, were employed to generate the questionnaire food list. Food frequency responses of 100 vegans from 19 different U.S. states were obtained via completed mailed questionnaires and compared to multiple telephone-conducted diet recall interviews. Computerized diet analyses were performed. Correlation coefficients, t-tests, rank, cross-tabulations, and probability tests were used to validate and compare intake estimates and dietary reference intake (DRI) assessment trends between the two methods. A 369-item vegan-specific questionnaire was developed with 252 listed food frequency items. Calorie-adjusted correlation coefficients ranged from r = 0.374 to 0.600 (p < 0.001) for all analyzed nutrients except calcium. Estimates, ranks, trends and higher-level participant percentile placements for Vitamin B₁₂ were similar with both methods. Questionnaire intakes were higher than recalls for most other nutrients. Both methods demonstrated similar trends in DRI adequacy assessment (e.g., significantly inadequate vitamin D intake among vegans). This vegan-specific questionnaire can be a useful assessment tool for health screening initiatives in U.S. vegan communities.

The association of binge eating and neighbourhood fast-food restaurant availability on diet and weight status

OBJECTIVE

Fast-food restaurants (FFR) are prevalent. Binge eating is common among overweight and obese women. For women prone to binge eating, neighbourhood FFR availability (i.e. the neighbourhood around one's home) may promote poor diet and overweight/obesity. The present study tested the effects of binge eating and neighbourhood FFR availability on diet (fat and total energy intake) and BMI among African American and Hispanic/Latino women.

DESIGN

All measures represent baseline data from the Health is Power randomized clinical trial. The numbers of FFR in participants' neighbourhoods were counted and dichotomized (0 or ≥1 neighbourhood FFR). Participants completed measures of binge eating status and diet. Weight and height were measured and BMI calculated. 2 (binge eating status) × 2 (neighbourhood FFR availability) ANCOVA tested effects on diet and BMI while controlling for demographics.

SETTING

Houston and Austin, TX, USA.

SUBJECTS

African American and Hispanic/Latino women aged 25-60 years.

RESULTS

Of the total sample (n 162), 48 % had 1-15 neighbourhood FFR and 29 % were binge eaters. There was an interaction effect on BMI (P = 0·05). Binge eaters with ≥1 neighbourhood FFR had higher BMI than non-binge eaters or binge eaters with no neighbourhood FFR. There were no significant interactions or neighbourhood FFR main effects on total energy or fat intake (P > 0·05). A main effect of binge eating showed that binge eaters consumed more total energy (P = 0·005) and fat (P = 0·005) than non-binge eaters.

CONCLUSIONS

Binge eaters represented a substantial proportion of this predominantly overweight and obese sample of African American and Hispanic/Latino women. The association between neighbourhood FFR availability and weight status is complicated by binge eating status, which is related to diet.

Dietary patterns of Pakistani adults and their associations with sociodemographic, anthropometric and life-style factors

Dietary pattern analysis is an epidemiological method designed to consider the complexity of food preferences and diet patterns of populations. Few studies from South Asia have used this methodology to describe population food intake. Our objective was to identify dietary patterns and understand their associations with sociodemographic, anthropometric and life-style factors among low-income Pakistani urban adults. Dietary information was collected by a thirty-three-item FFQ and dietary patterns were derived by principal component analyses in 5491 subjects enrolled in the Control of Blood Pressure and Risk Attenuation (COBRA) study. Three dietary patterns were identified: a fat and sweet pattern characterised by fried snacks/foods, desserts, organ meats, bakery products, Pakistani bread and food purchased from outside the home; a fruit and vegetable pattern including fruits, juices, raw and cooked vegetables, lean meat and low-fat milk; and a seafood and yogurt pattern identified by prawns, fish, potatoes and yogurt. The fat and sweet pattern scores were low among older subjects, those with high BMI and waist circumference but high among females and physically active participants. The fruit and vegetable pattern was associated with younger age, high BMI, education and non-tobacco use. The seafood and yogurt pattern was associated with high BMI, increased physical activity and non-tobacco use. In conclusion, distinct dietary patterns exist for the Pakistani population that may be related to some of the population characteristics and thus may have importance in suggesting dietary and life-style interventions in the prevention of chronic diseases.

Prospective study of genomic hypomethylation of leukocyte DNA and colorectal cancer risk

BACKGROUND

Systematic genome-wide reductions of methylated cytosine (5-mC) levels have been observed in colorectal cancer tissue and are suspected to play a role in carcinogenesis, possibly as a consequence of inadequate folate intake. Reduced 5-mC levels in peripheral blood leukocytes have been associated with increased risk of colorectal cancer and adenoma in cross-sectional studies.

METHODS

To minimize disease- and/or treatment-related effects, we studied leukocyte 5-mC levels in prospectively collected blood specimens of 370 cases and 493 controls who were cancer-free at blood collection from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. Leukocyte 5-mC level was determined by a high-pressure liquid chromatography (HPLC)/tandem mass spectrometry method and expressed as the relative amount of methyl to total cytosine residues, or %5-mC. We estimated the association between colorectal cancer risk and %5-mC categories by computing ORs and 95% confidence intervals (CI) through logistic regression modeling.

RESULTS

We observed no dose-dependent association between colorectal cancer and%5-mC categories (lowest vs. highest tertile: OR, 1.14; 95% CI, 0.80-1.63; P(trend) = 0.51). However, among subjects whose 5-mC levels were at the highest tertile, we observed an inverse association between natural folate intake and colorectal cancer (highest tertile of natural folate vs. lowest: OR, 0.35; 95% CI, 0.17-0.71; P(trend) = 0.003; P(interaction) = 0.003).

CONCLUSIONS

This prospective investigation show no clear association between leukocyte 5-mC level and subsequent colorectal cancer risk but a suggestive risk modification between 5-mC level and natural folate intake.

IMPACT

Adequate folate status may protect against colorectal carcinogenesis through mechanisms involving adequate DNA methylation in the genome.

Reliability and relative validity of a food frequency questionnaire to assess food group intakes in New Zealand adolescents

Background

Due to the absence of a current and validated food frequency questionnaire (FFQ) for use in New Zealand adolescents, there is a need to develop one as a cost-effective way to assess adolescents’ food patterns. This study aims to examine the test-retest reliability and relative validity of the New Zealand Adolescent FFQ (NZAFFQ) to assess food group intake in adolescents aged 14 to 18 years.

Methods

A non-quantitative (without portion size), 72-item FFQ was developed and pretested. Fifty-two participants (aged 14.9 ± 0.8 years) completed the NZAFFQ twice within a two-week period for test-retest reliability. Forty-one participants (aged 15.1 ± 0.9 years) completed a four-day estimated food record (4DFR) in addition to the FFQs to enable assessment of validity. Spearman’s correlations and cross-classification analyses were used to examine relative validity while intra-class correlations were additionally used for test-retest reliability.

Results

Weekly intakes were estimated for each food item and aggregated into 34 food groups. The median Spearman’s correlation coefficient (SCC) between FFQ administrations was 0.71. SCCs ranged from 0.46 for fruit juice or cordial to 0.87 for non-standard milk. The median intra-class correlation coefficient (ICC) between FFQ administrations was 0.69. The median SCC between food groups from the FFQ and the 4DFR was 0.40 with the highest SCC seen for standard milk (0.70). The exact agreement between the methods in ranking participants into thirds was highest for meat alternatives (78%), but lowest for red or yellow vegetables and potatoes (27%). The mean percent of participants misclassified into extreme thirds for food group intake was 12%.

Conclusions

Despite a small sample size, the NZAFFQ exhibited good to excellent short-term test-retest reliability and reasonable validity in ranking the majority of the food group intakes among adolescents aged 14 to 18 years. The comparability of the validity to that in the current literature suggests that the NZAFFQ may be used among adolescent New Zealanders to identify dietary patterns and rank them according to food group intake.

Food Intake Recording Software System, version 4 (FIRSSt4): a self-completed 24-h dietary recall for children

The Food Intake Recording Software System, version 4 (firsst4), is a web-based 24-h dietary recall (24 hdr) self-administered by children based on the Automated Self-Administered 24-h recall (ASA24) (a self-administered 24 hdr for adults). The food choices in firsst4 are abbreviated to include only those reported by children in US national surveys; and detailed food probe questions are simplified to exclude those that children could not be expected to answer (e.g. questions regarding food preparation and added fats). ASA24 and firsst4 incorporate 10 000+ food images, with up to eight images per food, to assist in portion size estimation. We review the formative research conducted during the development of firsst4. When completed, firsst4 will be hosted and maintained for investigator use on the National Cancer Institute's ASA24 website.

Alcohol, genetics and risk of breast cancer in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial

We tested the hypothesis that genes involved in the alcohol oxidation pathway modify the association between alcohol intake and breast cancer. Subjects were women aged 55-74 at baseline from the screening arm of the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. Incident breast cancers were identified through annual health surveys. Controls were frequency matched to cases by age and year of entry into the trial. A self-administered food frequency questionnaire queried frequency and usual serving size of beer, wine or wine coolers, and liquor. Three SNPs in genes in the alcohol metabolism pathway were genotyped: alcohol dehydrogenase 2, alcohol dehydrogenase 3, and CYP2E1. The study included 1,041 incident breast cancer cases and 1,070 controls. In comparison to non-drinkers, the intake of any alcohol significantly increased the risk of breast cancer, and this risk increased with each category of daily alcohol intake (OR 2.01, 95% CI 1.14, 3.53) for women who drank three or more standard drinks per day. Stratification by genotype revealed significant gene/environment interactions. For the ADH1B gene, there were statistically significant associations between all levels of alcohol intake and risk of breast cancer (all OR > 1.34 and all lower CI > 1.01), while for women with the GA or AA genotype, there were no significant associations between alcohol intake and risk of breast cancer. Alcohol intake, genes involved in alcohol metabolism and their interaction increase the risk of breast cancer in post-menopausal women. This information could be useful for primary care providers to personalize information about breast cancer risk reduction.

Associations between genes in the one-carbon metabolism pathway and advanced colorectal adenoma risk in individuals with low folate intake

BACKGROUND

Folate is essential for one-carbon metabolism, a pathway required by DNA synthesis, methylation, and repair. Low dietary and circulating folate and polymorphic variation in this pathway are associated with increased risk of colorectal adenoma and cancer.

METHODS

We genotyped 882 single nucleotide polymorphisms (SNP) in 82 one-carbon metabolism genes for 1,331 cases of advanced colorectal adenoma, identified by sigmoidoscopy at baseline, and 1,501 controls from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO). We evaluated associations between one-carbon genes and adenoma risk in all subjects and stratified by folate intake. We applied the Adaptive Rank Truncated Product (ARTP) method to assess statistical significance at the gene and pathway levels.

RESULTS

Folate intake was inversely associated with advanced colorectal adenoma risk [odds ratio (OR) by quartile = 0.85, P = 1.9 × 10(-5)]. We found no statistically significant associations between one-carbon genes and adenoma risk in all subjects. As hypothesized, we observed a statistically significant pathway-level association (P = 0.038) in the lowest quartile of folate; no significant associations were found in higher quartiles. Several genes including adenosine deaminase (ADA) and cysteine dioxygenase (CDO1) contributed to this signal (gene-level P = 0.001 and 0.0073, respectively). The most statistically significant SNP was rs244072 in ADA (P = 2.37 × 10(-5)).

CONCLUSIONS AND IMPACT

Stratification by dietary folate and application of the ARTP method revealed statistically significant pathway- and gene-level associations between one-carbon metabolism genes and risk of advanced colorectal adenoma, which were not apparent in analysis of the entire population. Folate intake may interact with associations between common variants in one-carbon metabolism genes and colorectal adenoma risk.

Computerized portion-size estimation compared to multiple 24-hour dietary recalls for measurement of fat, fruit, and vegetable intake in overweight adults

Validated self-report methods of dietary assessment exist and might be improved in terms of both accuracy and cost-efficiency with computer technology. The objectives of this preliminary study were to develop an initial version of an interactive CD-ROM program to estimate fruit, vegetable, and fat intake, and to compare it to multiple 24-hour dietary recalls (averaged over 3 days). In 2009, overweight male and female adults (n=205) from Lane County, OR, completed computerized and paper versions of fruit, vegetable, and fat screening instruments, and multiple 24-hour dietary recalls. Summary scores from the 10-item National Cancer Institute Fruit and Vegetable Scan and the 18-item Block Fat Screener were compared to multiple 24-hour dietary recall-derived fruit/vegetable and fat intake estimates (criterion measures). Measurement models were used to derive deattenuated correlations with multiple 24-hour dietary recalls of paper and CD-ROM administrations of Fruit and Vegetable Scan fruit intake, vegetable intake, and fruit and vegetable intake, and Block Fat Screener fat intake. The computerized assessment and paper surveys were related to multiple 24-hour dietary recall-derived fruit/vegetable and fat intake. Deattenuated correlation coefficients ranged from 0.50 to 0.73 (all P≤0.0001). The CD-ROM-derived estimate of fruit intake was more closely associated with 24-hour dietary recall (r=0.73) than the paper-derived estimate (r=0.54; P<0.05), but the other comparisons did not differ significantly. Findings from this preliminary study with overweight adults indicate the need for additional enhancements to the CD-ROM assessment and more extensive validation studies.

Food sources of nutrients among 13-year-old Portuguese adolescents

Objective

To identify food sources of nutrients in adolescents’ diets and to identify differences in food sources according to individual characteristics.

Design

A cross-sectional evaluation was carried out in the 2003/2004 school year. Self-administered questionnaires were used and a physical examination was performed. Diet was evaluated using an FFQ.

Setting

Public and private schools in Porto, Portugal.

Subjects

Adolescents aged 13 years (n 1522) enrolled at school.

Results

The main sources of energy were starchy foods (26·5 %), dairy (12·5 %) and meat (12·0 %). The major contributors to carbohydrate intake were starchy foods (38·2 %) and fruit (13·8 %) and to protein intake were meat (28·0 %), dairy products (20·3 %), starchy foods (15·3 %) and seafood (13·6 %). The main sources of total fat were meat (22·0 %), starchy foods (13·4 %) and dairy products (12·7 %). Sweets and pastries presented important contributions to energy (11·1 %), carbohydrate (12·4 %), total fat (13·3 %) and saturated fat (16·6 %) intakes. Parental education was inversely associated with the contribution of sweets and pastries to energy, carbohydrate and fat intakes and it was positively associated with the seafood contribution to protein intake.

Conclusions

The major sources of carbohydrates were starchy foods, which also accounted for a quarter of energy intake. Dairy products plus meat accounted for another quarter of energy. Meat was a major source of protein and fats. Sweets and pastries contributed more than 10 % to energy, carbohydrates, total and saturated fat. Parental education was the strongest determinant of food sources and was positively associated with a healthier contribution of food groups.

A prospective cohort study of dietary patterns of non-western migrants in the Netherlands in relation to risk factors for cardiovascular diseases: HELIUS-Dietary Patterns

Background

In Western countries the prevalence of cardiovascular disease (CVD) is often higher in non-Western migrants as compared to the host population. Diet is an important modifiable determinant of CVD. Increasingly, dietary patterns rather than single nutrients are the focus of research in an attempt to account for the complexity of nutrient interactions in foods. Research on dietary patterns in non-Western migrants is limited and may be hampered by a lack of validated instruments that can be used to assess the habitual diet of non-western migrants in large scale epidemiological studies. The ultimate aims of this study are to (1) understand whether differences in dietary patterns explain differences in CVD risk between ethnic groups, by developing and validating ethnic-specific Food Frequency Questionnaires (FFQs), and (2) to investigate the determinants of these dietary patterns. This paper outlines the design and methods used in the HELIUS-Dietary Patterns study and describes a systematic approach to overcome difficulties in the assessment and analysis of dietary intake data in ethnically diverse populations.

Methods/Design

The HELIUS-Dietary Patterns study is embedded in the HELIUS study, a Dutch multi-ethnic cohort study. After developing ethnic-specific FFQs, we will gather data on the habitual intake of 5000 participants (18-70 years old) of ethnic Dutch, Surinamese of African and of South Asian origin, Turkish or Moroccan origin. Dietary patterns will be derived using factor analysis, but we will also evaluate diet quality using hypothesis-driven approaches. The relation between dietary patterns and CVD risk factors will be analysed using multiple linear regression analysis. Potential underlying determinants of dietary patterns like migration history, acculturation, socio-economic factors and lifestyle, will be considered.

Discussion

This study will allow us to investigate the contribution of the dietary patterns on CVD risk factors in a multi-ethnic population. Inclusion of five ethnic groups residing in one setting makes this study highly innovative as confounding by local environment characteristics is limited. Heterogeneity in the study population will provide variance in dietary patterns which is a great advantage when studying the link between diet and disease.