Relative validity of adolescent dietary patterns: a comparison of a FFQ and 3 d food record

Relationship between dietary intake and erythrocyte PUFA in adolescents from a Western Australian cohort

BACKGROUND

Population-based studies show that the intake of omega-3 (n-3) and omega-6 (n-6) polyunsaturated fatty acids (PUFA) are associated with a range of health conditions. Therefore, the reliability of food frequency questionnaires (FFQ) as rapid and easily accessible screening tools for PUFA intake deserve investigation.

OBJECTIVE

We aimed to assess the relationship between erythrocyte fatty acids and fatty acid intake collected using the Commonwealth Scientific and Industrial Research Organisation (CSIRO) food frequency questionnaire in an adolescent cohort.

DESIGN

A cross-sectional study using data from 1155 young adolescents participating in the 14-year follow-up of the Raine Study. Bland-Altman plots were used to determine the agreement between dietary intake and erythrocyte levels of each fatty acid.

RESULTS

The main dietary source of n-3 long-chain (LC) PUFA was 'fresh fish' (53% of total n-3 LC-PUFA). Docosahexaenoic acid (DHA) showed the strongest correlation between erythrocyte and diet assessment (r = 0.274; p < 0.001), whilst linoleic acid (LA) (r = 0.103; p < 0.001) and arachidonic acid (AA) (r = -0.06; p = 0.042) showed weaker correlations, with limits of agreement relatively narrow. Bland-Altman plots showed a dose-dependent bias between the FFQ fatty acid data and corresponding erythrocyte data.

CONCLUSIONS

For the major n-3 and n-6 PUFA, dietary intakes derived from the FFQ showed weaker correlations and poorer agreement with erythrocyte levels, and the deviation between the two increased with higher intake levels.

Prospective dietary polyunsaturated fatty acid intake is associated with trajectories of fatty liver disease: an 8 year follow-up study from adolescence to young adulthood

BACKGROUND AND AIM

Dietary fat intake has long been associated with fatty liver. Our study aimed to determine the effect of dietary fats on longitudinal fatty liver index (FLI) trajectories from adolescence to young adulthood.

METHODS

Nine hundred eighty-five participants in the Raine Study, Perth, Western Australia, Australia, had cross-sectional assessments at ages 14, 17, 20 and 22 years, during which anthropometric measurements and blood tests were obtained. FLI trajectories were derived from the longitudinal FLI results. Dietary fat intake was measured with a semi-quantitative food frequency questionnaire at 14 years and log multinominal regression analyses were used to estimate relative risks.

RESULTS

Three FLI trajectories were identified and labelled as stable-low (79.1%, N = 782), low-to-high (13.9%, N = 132), and stable-high (7%, N = 71). The low-to-high group associated with an increased intake of the long-chain polyunsaturated fatty acids EPA, DPA and DHA (RR 1.27, 95% CI 1.10-1.48) relative to the stable-low group. Compared to the stable-low group, omega-6 and the ratio of omega-6 to omega-3 in the stable-high group were associated with an increased relative risk of 1.34 (95% CI 1.02-1.76) and 1.10 (95% CI 1.03-1.16), respectively.

CONCLUSION

For those at high risk of fatty liver in early adolescence, high omega-6 fatty acid intake and a high ratio of omega-6 to omega-3 fatty acids are associated with increased risk of fatty liver. There should be caution in assuming these associations are causal due to possible undetected and underestimated confounding factors.

Dietary Patterns of 479 Indonesian Adults and Their Associations with Sodium and Potassium Intakes Estimated by Two 24-h Urine Collections

The excess sodium (Na) intake and insufficient potassium (K) intake are frequently observed all over the world, including Indonesia. This study explored the dietary patterns of Indonesian people and evaluated their associations with Na and K intakes. Na and K intakes were assessed by repeated 24-h urine collection. The dietary patterns of the previous month were extracted by factor analysis using the Indonesian Food Frequency Questionnaire. The participants were community-dwelling Indonesian men and women (n = 479) aged 20 years and over. We identified four dietary patterns in each sex. After controlling for confounding factors, the high quantile of ‘Noodle, oil, and salty sea products’ pattern was associated with the high Na intake in both men and women (p = 0.02 and <0.001, respectively). The ‘Meat, vegetable, oil, and fruit’ pattern statistically significantly contributed to the high K intake in men (p = 0.04), but not in women (p = 0.26). The ‘Vegetable, non-oil, and milk’ pattern in men and ‘Meat, vegetable, and fruit’ pattern in women were associated with low Na:K ratios (p = 0.03 and 0.01, respectively). Neither ‘bread’ nor ‘fish’ appeared as a major determinant of any dietary patterns in this population. The ‘Noodle, oil, and salty sea products’ pattern should be avoided to reduce sodium intake.

The Reproducibility and Relative Validity of a Food Frequency Questionnaire for Identifying Iron-Related Dietary Patterns in Pregnant Women

Analyzing pregnant women’s iron intake using dietary patterns would provide information that considers dietary relationships with other nutrients and their sources. The objective of this study was to evaluate the reproducibility and relative validity of a Qualitative Food Frequency Questionnaire to identify iron-related dietary patterns (FeP-FFQ) among Mexican pregnant women. A convenience sample of pregnant women (n = 110) completed two FeP-FFQ (FeP-FFQ1 and FeP-FFQ2) and a 3-day diet record (3DDR). Foods appearing in the 3DDR were classified into the same food groupings as the FeP-FFQ, and most consumed foods were identified. Exploratory factor analysis was used to determine dietary patterns. Scores were compared (FeP-FFQ for reproducibility and FeP-FFQ1 vs. 3DDR for validity) through intraclass correlation coefficients (ICC), cross-classification, Bland−Altman analysis, and weighed Cohen kappa (κw), using dietary patterns scores tertiles. Two dietary patterns were identified: “healthy” and “processed foods and dairy”. ICCs (p < 0.01) for “healthy” pattern and “processed foods and dairy” pattern were 0.76 for and 0.71 for reproducibility, and 0.36 and 0.37 for validity, respectively. Cross-classification and Bland−Altman analysis showed good agreement for reproducibility and validity; κw values showed moderate agreement for reproducibility and low agreement for validity. In conclusion, the FeP-FFQ showed good indicators of reproducibility and validity to identify dietary patterns related to iron intake among pregnant women.

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.

Identification and reproducibility of dietary patterns assessed with a FFQ among women planning pregnancy

OBJECTIVE

To identify a posteriori dietary patterns among women planning pregnancy and assess the reproducibility of these patterns in a subsample using two dietary assessment methods.

DESIGN

A semi-quantitative FFQ was administered to women enrolled in the Singapore PREconception Study of long-Term maternal and child Outcomes study. Dietary patterns from the FFQ were identified using exploratory factor analysis (EFA). In a subsample of women (n 289), 3-d food diaries (3DFD) were also completed and analysed. Reproducibility of the identified patterns was assessed using confirmatory factor analysis (CFA) in the subsample, and goodness of fit of the CFA models was examined using several fit indices. Subsequently, EFA was conducted in the subsample and dietary patterns of the FFQ and the 3DFD were compared.

SETTING

Singapore.

PARTICIPANTS

1007 women planning pregnancy (18-45 years).

RESULTS

Three dietary patterns were identified from the FFQ: the 'Fish, Poultry/Meat and Noodles' pattern was characterised by higher intakes of fish, poultry/meat and noodles in soup; 'Fast Food and Sweetened Beverages' pattern was characterised by higher intakes of fast food, sweetened beverages and fried snacks; 'Bread, Legumes and Dairy' pattern was characterised by higher intakes of buns/ethnic breads, nuts/legumes and dairy products. The comparative fit indices from the CFA models were 0·79 and 0·34 for the FFQ and 3DFD of the subsample, respectively. In the subsample, three similar patterns were identified in the FFQ while only two for the 3DFD.

CONCLUSIONS

Dietary patterns from the FFQ are reproducible within this cohort, providing a basis for future investigations on diet and health outcomes.

Dietary fibre intake and its associations with depressive symptoms in a prospective adolescent cohort

Depression is a major cause of disability in adolescents. Higher dietary fibre intake has been associated with lower depressive symptoms in adults, but there is a lack of research in adolescents. We examined the association between dietary fibre intake (Commonwealth Scientific and Industrial Research Organisation (CSIRO) FFQ) and depressive symptoms (Beck Depression Inventory for Youth) in adolescents with prospective data from the Raine Study Gen2 14- and 17-year follow-ups (n 1260 and 653). Odds of moderate/extreme (clinically relevant) depressive symptoms by quartile of fibre intake were calculated using mixed-effects logistic regression for all participants, in a paired sample without moderate/extreme depressive symptoms at 14 years and in a sub-sample of participants with available inflammatory data at the ages of 14 and 17 years (n 718 and 547). Odds of moderate/extreme depressive symptoms were lower in the fourth (highest) quartile of overall fibre intake (OR 0·273, 95 % CI 0·09, 0·81) compared with the first (lowest) quartile, adjusting for sex, age, energy intake, adiposity, and family and lifestyle factors. However, further adjustment for dietary patterns attenuated the results. Associations of depressive symptoms with cereal or fruit and vegetable fibre intake were not significant in the final model. Adjustment for inflammation had no effect on OR. The association between a higher dietary fibre intake and lower odds of clinically relevant depressive symptoms may be more reflective of a high-fibre diet with all its accompanying nutrients than of an independent effect of fibre.

Dietary pattern trajectories across adolescence and early adulthood and their associations with childhood and parental factors

BACKGROUND

Although adolescent dietary patterns tend to be of poor quality, it is unclear whether dietary patterns established in adolescence persist into adulthood.

OBJECTIVES

We examined trajectories across adolescence and early adulthood for 2 major dietary patterns and their associations with childhood and parental factors.

METHODS

Using data from the Western Australian Pregnancy Cohort (Raine Study), intakes of 38 food groups were estimated at ages 14, 17, 20 and 22 y in 1414 participants using evaluated FFQs. Using factor analysis, 2 major dietary patterns (healthy and Western) were consistently identified across follow-ups. Sex-specific group-based modeling assessed the variation in individual dietary pattern z scores to identify group trajectories for each pattern between ages 14 and 22 y and to assess their associations with childhood and parental factors.

RESULTS

Two major trajectory groups were identified for each pattern. Between ages 14 and 22 y, a majority of the cohort (70% males, 73% females) formed a trajectory group with consistently low z scores for the healthy dietary pattern. The remainder had trajectories showing either declining (27% females) or reasonably consistent healthy dietary pattern z scores (30% males). For the Western dietary pattern, the majority formed trajectories with reasonably consistent average scores (79% males, 81% females) or low scores that declined over time. However, 21% of males had a trajectory of steady, marked increases in Western dietary pattern scores over time. A lower maternal education and higher BMI (in kg/m2) were positively associated with consistently lower scores of the healthy dietary pattern. Lower family income, family functioning score, maternal age, and being in a single-parent family were positively related to higher scores of the Western dietary pattern.

CONCLUSIONS

Poor dietary patterns established in adolescence are likely to track into early adulthood, particularly in males. This study highlights the transition between adolescence and early adulthood as a critical period and the populations that could benefit from dietary interventions.

The reliability and relative validity of predefined dietary patterns were higher than that of exploratory dietary patterns in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam population

The aim of this study was to assess the ability of the FFQ to describe reliable and valid dietary pattern (DP) scores. In a total of 134 participants of the European Prospective Investigation into Cancer and Nutrition-Potsdam study aged 35–67 years, the FFQ was applied twice (baseline and after 1 year) to assess its reliability. Between November 1995 and March 1997, twelve 24-h dietary recalls (24HDR) as reference instrument were applied to assess the validity of the FFQ. Exploratory DP were derived by principal component analyses. Investigated predefined DP were the Alternative Healthy Eating Index (AHEI) and two Mediterranean diet indices. From dietary data of each FFQ, two exploratory DP were retained, but differed in highly loading food groups, resulting in moderate correlations (r 0·45–0·58). The predefined indices showed higher correlations between the FFQ (r(AHEI) 0·62, r(Mediterranean Diet Pyramid Index (MedPyr)) 0·62 and r(traditional Mediterranean Diet Score (tMDS)) 0·51). From 24HDR dietary data, one exploratory DP retained differed in composition to the first FFQ-based DP, but showed similarities to the second DP, reflected by a good correlation (r 0·70). The predefined DP correlated moderately (r 0·40–0·60). To conclude, long-term analyses on exploratory DP should be interpreted with caution, due to only moderate reliability. The validity differed extensively for the two exploratory DP. The investigated predefined DP showed a better reliability and a moderate validity, comparable to other studies. Within the two Mediterranean diet indices, the MedPyr performed better than the tMDs in this middle-aged, semi-urban German study population.

Changes in dietary patterns when females engage in a weight management programme and their ability to meet Scientific Advisory Committee on Nutrition’s fibre and sugar recommendations

Objective:

To investigate how dietary patterns (DP) change following engagement in a weight management programme. Using the DP identified, to study their relationship with weight loss achieved and ability to meet the Scientific Advisory Committee on Nutrition’s 2015 fibre and sugar recommendations.

Design:

Secondary analysis of FFQ data, which collected dietary information at two time points: retrospectively before (T0) and presently during (T1) Slimming World’s programme, was analysed. Principal component analysis derived the DP present.

Setting:

Online FFQ, hosted by Slimming World (SW) in the UK.

Participants:

Female SW members (n 325; 17–68 years old).

Results:

At T0, two DP, ‘plant based’ and ‘processed meat and sugar added by the consumer’ were identified. At T1, three DP were identified, ‘high meat’, ‘high fat salt and sugar (HFSS) products’ and ‘nuts and oils’. Participants with a diet low in ‘HFSS products’ lost significantly more weight (P for trend = 0·001), were more likely to consume breakfast (P = 0·021) and consumed less free sugar compared with high ‘HFSS product’ consumers. Those initially presenting with a low ‘plant based’ diet score lost more weight at T1 (P for trend = 0·046). With engagement, mean fibre intake increased from 24·3 to 32·4 g/d (P < 0·001) and free sugar intake decreased from 12·6 to 8·7 % total dietary energy (P < 0·001).

Conclusions:

An individual’s DP before and with engagement in a weight management programme may indicate their weight loss success. Advising reduced HFSS product intake may aid initial weight loss. SW appears to promote dietary changes towards UK fibre and sugar recommendations.

The mediating effect of dietary patterns on the association between mother's education level and the physical aggression of five-year-old children: a population-based cohort study

BACKGROUND

Relatively few studies have investigated the effects of diet on behavior problems among preschoolers, particularly, physical aggression. In addition, children raised by poorly educated mothers usually have a higher probability of developing negative outcomes. Additionally, highly educated mothers have a higher probability of providing more healthy foods for their children. Thus, mothers providing healthy foods might mitigate children's behavior problems. The study aims to examine whether preschoolers' dietary pattern, as a manipulable factor, mediates the association between maternal education level and physical aggression.

METHODS

Data came from the Taiwan Birth Cohort Study (TBCS), a nationally representative population-based cohort study, which included 18,513 five-year-old Taiwanese children. Mothers and primary caregivers reported the information on preschoolers' physical aggression and food consumption at age 5 and maternal education level at age 6 months. Two dietary patterns, namely a healthy diet and a high-fat-sugar-salt (HFSS) diet, were retrieved by exploratory factor analysis. Mediation hypotheses were tested by a series of multiple regression models conducted using the PROCESS macro of SAS 9.4. All models were adjusted for children's sex, parental marital status, household income, mental distress at age 5 and children's physical aggression at age 3.

RESULTS

Maternal education positively linked to healthy dietary patterns (B = 0.014, p = 0.002) which was negatively associated with preschoolers' physical aggression (B = -0.096, p = 0.013), and it is negatively related to the HFSS dietary pattern (B = -0.042, p = 0.002) which was directly positively associated with preschoolers' physical aggression (B = 0.123, p = 0.008). The association between maternal education and preschoolers' physical aggression was partially mediated by preschoolers' healthy (B = -0.001, p < .001) and HFSS (B = -0.005, p = <.001) dietary patterns, respectively. The R-square of the mediation model is 0.178.

CONCLUSIONS

Preschoolers' dietary patterns directly associate with their physical aggression. In addition, mothers with poor education may provide less healthy foods and more unhealthy foods to their children, which may increase the level of physical aggression. The results imply partial mediating effects of dietary patterns between maternal education and physical aggression. It is suggested that a parent-based nutritional education program focusing on healthy meal preparation for poor educated mothers might be beneficial for preschoolers' healthy development.

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.

Differences in dietary fibre intake and associated familial factors in a longitudinal study at two time points across adolescence

OBJECTIVE

Dietary fibre is essential for a healthy diet; however, intake is often inadequate. Understanding of sources of dietary fibre and familial factors associated with intake in adolescents is limited, hampering efforts to increase intake. We aimed to determine adequacy of dietary fibre intake in adolescents, examine how intake changes from mid to late adolescence, identify major food sources and explore associations with familial factors.

DESIGN

Dietary fibre intake measured with semi-quantitative FFQ and sources calculated with the AUSNUT database. Familial factors determined by questionnaire.

SETTING

Western Australian Pregnancy Cohort (Raine) Study.

PARTICIPANTS

Generation 2 adolescents from the 14- (n 1626) and 17-year (n 835) follow-ups.

RESULTS

Mean intake of dietary fibre did not meet national dietary guidelines other than for females aged 14 years. Mean intake of both sexes was lower at 17 years (23·0 (sd 10·0) g/d) than at 14 years (24·3 (sd 9·0) g/d, P < 0·001). The quantity of dietary fibre consumed per megajoule also decreased (2·6 (sd 0·7) g/MJ at 14 years, 2·5 (sd 0·9) g/MJ at 17 years, P = 0·007). The greatest source of dietary fibre was cereals and grains, followed by fruits, then vegetables. In multivariable mixed-model analysis, female sex, Caucasian race, age 14 years, good family functioning, high level of parental education and high energy intake were independently associated with higher dietary fibre intake.

CONCLUSIONS

Our study highlights an age range and characteristics of adolescents lacking in dietary fibre, thereby identifying target populations for interventions to improve dietary fibre intake across adolescence, which would lead to better health.

Development and validation of the semi-quantitative brief food frequency questionnaire to assess the magnesium intake in young women

AIM

The aim of the study was to develop and validate the semi-quantitative brief food frequency questionnaire to assess the magnesium intake (Mg-FFQ).

METHODS

The developed questionnaire consists of 39 questions and it was validated in a group of 75 women aged 20-30. The validity was assessed with reference to the 3-day dietary record and the reproducibility was assessed for a period of 6 weeks.

RESULTS

The Bland-Altman index for the assessment of validity was 6.7% and for reproducibility-8.0%, while the kappa statistic indicated a slight and substantial agreement, respectively. The high reproducibility was confirmed by a high share of respondents correctly classified into tertiles (73.3%) and correctly classified into categories of adequate/inadequate intake (85.3%).

CONCLUSION

For the developed and validated Mg-FFQ, a high reproducibility, accompanied by a satisfactory validity, was confirmed, so it may be used to assess the magnesium intake in the epidemiological studies in young Polish women aged 20-30.

Dietary patterns and hearing loss in older men enrolled in the Caerphilly Study

The association between dietary patterns (DP) and prevalence of hearing loss in men enrolled in the Caerphilly Prospective Study was investigated. During 1979-1983, the study recruited 2512 men aged 45-59 years. At baseline, dietary data were collected using a semi-quantitative FFQ, and a 7-d weighed food intake (WI) in a 30 % subsample. Five years later, pure-tone unaided audiometric threshold was assessed at 0·5, 1, 2 and 4 kHz. Principal component analysis (PCA) identified three DP and multiple logistic and ordinal logistic regression models examined the association with hearing loss (defined as pure-tone average of frequencies 0·5, 1, 2 and 4 kHz &gt;25 dB). Traditional, healthy and high-sugar/low-alcohol DP were found with both FFQ and WI data. With the FFQ data, fully adjusted models demonstrated significant inverse association between the healthy DP and hearing loss both as a dichotomous variable (OR=0·83; 95 % CI 0·77, 0·90; P&lt;0·001) and as an ordinal variable (OR=0·87; 95 % CI 0·81, 0·94; P&lt;0·001). With the WI data, fully adjusted models showed a significant and inverse association between the healthy DP and hearing loss (OR=0·85; 95 % CI 0·73, 0·99; P&lt;0·03), and a significant association between the traditional DP (per fifth increase) and hearing loss both as a dichotomous variable (OR=1·18; 95 % CI 1·02, 1·35; P=0·02) and as an ordinal variable (OR=1·17; 95 % CI 1·03, 1·33; P=0·02). A healthy DP was significantly and inversely associated with hearing loss in older men. The role of diet in age-related hearing loss warrants further investigation.

Parents' Reports of Preschoolers' Diets: Relative Validity of a Food Frequency Questionnaire and Dietary Patterns

The accurate assessment of food consumption is crucial in nutritional studies. Since modern nutrition science has become more interested in diet as a whole, studies validating food frequency questionnaires (FFQs) and exploratory dietary patterns are needed. We aimed at examining the relative validity of a 47-item FFQ against three-day food records among three- to six-year-old Finnish children, as well as investigating the consistency of the dietary patterns derived using the principal component analysis (PCA), with food record and FFQ data as inputs. We conducted the PCA without forcing the food record data to match the FFQ items. Altogether, 75% or more of the participants were classified into the same or adjacent quarter of vegetables and fruits as well as sugary food consumption. Furthermore, the intake of folate and vitamin C increased linearly in the quarters of vegetable and fruit consumption, as did the intake of sucrose in quarters of sugary food consumption. Three fairly similar dietary patterns were identified from food records and FFQ data. Concerning the patterns, more than 70% of the participants were classified into the same or adjacent quarter. However, the Spearman correlation coefficients between the respective pattern scores were low (0.25–0.33). The FFQ showed acceptable validity when ranking food group consumption compared to food records. Additionally, the FFQ-derived dietary patterns were consistent with those derived using food record data.

A healthy dietary pattern associates with a lower risk of a first clinical diagnosis of central nervous system demyelination

BACKGROUND

The evidence associating diet and risk of multiple sclerosis is inconclusive.

OBJECTIVE

We investigated associations between dietary patterns and risk of a first clinical diagnosis of central nervous system demyelination, a common precursor to multiple sclerosis.

METHODS

We used data from the 2003-2006 Ausimmune Study, a case-control study examining environmental risk factors for a first clinical diagnosis of central nervous system demyelination, with participants matched on age, sex and study region. Using data from a food frequency questionnaire, dietary patterns were identified using principal component analysis. Conditional logistic regression models (n = 698, 252 cases, 446 controls) were adjusted for history of infectious mononucleosis, serum 25-hydroxyvitamin D concentrations, smoking, race, education, body mass index and dietary misreporting.

RESULTS

We identified two major dietary patterns - healthy (high in poultry, fish, eggs, vegetables, legumes) and Western (high in meat, full-fat dairy; low in wholegrains, nuts, fresh fruit, low-fat dairy), explaining 9.3% and 7.5% of variability in diet, respectively. A one-standard deviation increase in the healthy pattern score was associated with a 25% reduced risk of a first clinical diagnosis of central nervous system demyelination (adjusted odds ratio 0.75; 95% confidence interval 0.60, 0.94; p = 0.011). There was no statistically significant association between the Western dietary pattern and risk of a first clinical diagnosis of central nervous system demyelination.

CONCLUSION

Following healthy eating guidelines may be beneficial for those at high risk of multiple sclerosis.

Exploratory dietary patterns: a systematic review of methods applied in pan-European studies and of validation studies

Besides a priori approaches, using previous knowledge about food characteristics, exploratory dietary pattern (DP) methods, using data at hand, are commonly applied. This systematic literature review aimed to identify exploratory methods on DP in pan-European studies and to inform the development of the DEterminants of DIet and Physical ACtivity (DEDIPAC) toolbox of methods suitable for use in future European studies. The search was conducted in three databases on prospective studies in healthy, free-living people across the whole life span. To identify validated DP methods, an additional search without regional restrictions was conducted. Studies including at least two European countries were retained. The search resulted in six pan-European studies applying principal component/factor analysis (PC/FA) (n 5) or cluster analysis (n 2). The criteria to retain PC/factors ranged from the application of the eigenvalue>1 criterion, the scree plot and/or the interpretability criterion. Furthermore, seven validation studies were identified: DP, derived by PC/FA (n 6) or reduced rank regression (RRR) (n 1) were compared using dietary information from FFQ (n 6) or dietary history (n 1) as study instrument and dietary records (n 6) or 24-h dietary recalls (n 1) as reference. The correlation coefficients for the derived DP ranged from modest to high. To conclude, PC/FA was predominantly applied using the eigenvalue criterion and scree plot to retain DP, but a better description of the applied criteria is highly recommended to enable a standardised application of the method. Research gaps were identified for the methods cluster analysis and RRR, as well as for validation studies on DP.

Test-Retest Reproducibility of Adult-Reported High School Diet Varies among Racially and Ethnically Diverse US Men and Women

Background

Adolescent diet is thought to play an important role in future chronic disease risk. However, few studies have examined the reproducibility of adult-reported adolescent diet, and evidence for possible differences in reproducibility by demographic characteristics is limited.

Objective

We assessed the ability of adults to consistently report past high school diet over a 1-y period and examined differences in reproducibility by selected demographic characteristics.

Methods

By using age-adjusted partial Spearman (ρ) or Pearson (r) correlations, we assessed 1-y reproducibility for 33 line items, 20 food groups, and 2 dietary patterns of high school diet reported in adulthood via a questionnaire completed by 742 participants in the Cancer Prevention Study 3 (CPS-3) Diet Substudy.

Results

Participants' median age was 53 y (range: 31-70 y), 65.2% were women, 59.8% were non-Hispanic white, 24.8% were non-Hispanic black, and 15.4% were Hispanic. The mean Spearman correlation assessing reproducibility across the 33 line items was 0.60 and ranged from 0.44 to 0.72, with no differences in mean correlations by age, sex, race/ethnicity, education, or body mass index (BMI). Reproducibility was similar across food groups (ρ = 0.62; range: 0.44-0.68), with differences by sex, ethnicity, age, or BMI observed for some food groups (e.g., sugar-sweetened beverages). Pearson correlations for the reproducibility of 2 major eating patterns, "fast food" and "whole food," were 0.73 and 0.72, respectively.

Conclusion

These results show good 1-y reproducibility of assessed high school diet, as reported from memory in adulthood, by line item, food group, and dietary pattern, with noted differences by demographic characteristics.

Dietary patterns, body mass index and inflammation: Pathways to depression and mental health problems in adolescents

BACKGROUND

Observational studies suggest that dietary patterns may impact mental health outcomes, although biologically plausible pathways are yet to be tested. We aimed to elucidate the longitudinal relationship between dietary patterns, adiposity, inflammation and mental health including depressive symptoms in a population-based cohort of adolescents.

METHODS

Data were provided from 843 adolescents participating in the Western Australian Pregnancy Cohort (Raine) Study at 14 and 17 years (y) of age. Structural equation modelling was applied to test our hypothesised models relating dietary patterns, energy intake and adiposity (body mass index) at 14 y to adiposity and the pro-inflammatory adipokine (leptin) and inflammation (high sensitivity C-reactive protein - hs-CRP) at 17 y, and these inflammatory markers to depressive symptoms (Beck Depression Inventory) and Internalising and Externalising Behavioral Problems (Child Behavior Check List Youth Self- Report) at 17 y. We further tested a reverse hypothesis model, with depression at 14 y as a predictor of dietary patterns at the same time-point.

RESULTS

The tested models provided a good fit to the data. A 'Western' dietary pattern (high intake of red meat, takeaway, refined foods, and confectionary) at 14 y was associated with higher energy intake and BMI at 14 y, and with BMI and biomarkers of inflammation at 17 y (all p < .05). A 'Healthy' dietary pattern (high in fruit, vegetables, fish, whole-grains) was inversely associated with BMI and inflammation at 17 y (p < .05). Higher BMI at 14 y was associated with higher BMI (p < .01), leptin (p < .05), hs-CRP (p < .05), depressive symptoms (p < .05) and mental health problems (p < .05), all at 17 y.

CONCLUSION

A 'Western' dietary pattern associates with an increased risk of mental health problems including depressive symptoms in adolescents, through biologically plausible pathways of adiposity and inflammation, whereas a 'Healthy' dietary pattern appears protective in these pathways. Longitudinal modelling into adulthood is indicated to confirm the complex associations of dietary patterns, adiposity, inflammation and mental health problems, including depressive symptoms.

[Dietary habits of adolescents and associated cardiovascular risk factors: a systematic review]

The scope of this study was to conduct a systematic review to establish the major dietary habits of adolescents and the corresponding association with cardiovascular risk factors. Research was performed in the LILACS, SciELO, PubMed, Scopus and Web of Science databases in addition to a manual search for original articles published between 2005 and 2014. Of the 371 entries identified; 26 fulfilled the inclusion criteria and were covered in the review. The main dietary habits observed were Western (61%) Healthy (42%) and Traditional (38%). Western dietary habits were positively associated with total cholesterol and SM, while Healthy dietary habits were inversely associated with fasting glycaemia, DBP and SM and positively with HDL-C, all of the aforementioned associations with very low (D) quality of evidence in accordance with the GRADE rating. The Traditional dietary habits were considered a risk factor for hyperglycemia, hyperinsulinemia and hypertriglyceridemia and protection for physical activity and eutrophic BMI. Although these results need to be analyzed with caution, due to the low quality of evidence, there is a clear need for actions aimed at promoting healthy dietary habits in adolescents in order to contribute to the prevention of cardiovascular risk factors.

Comparative validity and repeatability of a single question, a twenty-eight-item FFQ and estimated food records to assess takeaway meal intake

A single question (SQ) and a twenty-eight-item FFQ to measure takeaway meal intake were compared with two 7-d estimated food records (EFR; reference method). Test methods were completed after the reference period and repeated 6-8 d later for repeatability. The SQ asked about intake of high-SFA takeaway meals. FFQ items included low- and high-SFA meals. Test methods were compared with EFR for sensitivity, specificity, and positive and negative predictive values, using a goal of ≤1 high-SFA weekly takeaway meals. Bland-Altman analyses were used to check agreement between measurement approaches, the κ coefficient was used to summarise the observed level of agreement, and Spearman's correlation was used to assess the degree to which instruments ranked individuals. Young adults were recruited from two universities, and 109 participants (61 % female) completed the study. The mean age was 24·4 (sd 4·9) years, and the mean BMI was 23·5 (sd 3·7) kg/m2. The SQ and the FFQ had a sensitivity of 97 and 83 % and a specificity of 46 and 92 %, respectively. Both methods exhibited moderate correlation for measuring total and high-SFA takeaway meal intakes (r s ranging from 0·64 to 0·80). Neither instrument could measure precise, absolute intake at the group or individual level. Test methods ranged from fair (κ w =0·24) to moderate agreement (κ w =0·59). The repeatability for all was acceptable. The FFQ identified excessive high-SFA takeaway meal intake and measured individuals' category for total and high-SFA takeaway intakes. Both methods are suitable for ranking individuals for total or high-SFA takeaway meal intakes.

Evaluating the Applicability of Data-Driven Dietary Patterns to Independent Samples with a Focus on Measurement Tools for Pattern Similarity

BACKGROUND

Diet is a key modifiable risk for many chronic diseases, but it remains unclear whether dietary patterns from one study sample are generalizable to other independent populations.

OBJECTIVE

The primary objective of this study was to assess whether data-driven dietary patterns from one study sample are applicable to other populations. The secondary objective was to assess the validity of two criteria of pattern similarity.

METHODS

Six dietary patterns-Western (n=3), Mediterranean, Prudent, and Healthy- from three published studies on breast cancer were reconstructed in a case-control study of 973 breast cancer patients and 973 controls. Three more internal patterns (Western, Prudent, and Mediterranean) were derived from this case-control study's own data.

STATISTICAL ANALYSIS

Applicability was assessed by comparing the six reconstructed patterns with the three internal dietary patterns, using the congruence coefficient (CC) between pattern loadings. In cases where any pair met either of two commonly used criteria for declaring patterns similar (CC ≥0.85 or a statistically significant [P<0.05] Pearson correlation), then the true similarity of those two dietary patterns was double-checked by comparing their associations to risk for breast cancer, to assess whether those two criteria of similarity are actually reliable.

RESULTS

Five of the six reconstructed dietary patterns showed high congruence (CC >0.9) to their corresponding dietary pattern derived from the case-control study's data. Similar associations with risk for breast cancer were found in all pairs of dietary patterns that had high CC but not in all pairs of dietary patterns with statistically significant correlations.

CONCLUSIONS

Similar dietary patterns can be found in independent samples. The P value of a correlation coefficient is less reliable than the CC as a criterion for declaring two dietary patterns similar. This study shows that diet scores based on a particular study are generalizable to other populations.

Reproducibility and Relative Validity of a Short Food Frequency Questionnaire in 9-10 Year-Old Children

The aim of this study was to assess the reproducibility and validity of a non-quantitative 28-item food frequency questionnaire (FFQ). Children aged 9-10 years (n = 50) from three schools in Dunedin, New Zealand, completed the FFQ twice and a four-day estimated food diary (4DEFD) over a two-week period. Intraclass correlation coefficients (ICC) and Spearman's correlation coefficients (SCC) were used to determine reproducibility and validity of the FFQ, respectively. Weekly intakes were estimated for each food item and aggregated into 23 food items/groups. More than half of the food items/groups (52.2%) had an ICC ≥0.5. The median SCC between FFQ administrations was 0.66 (ranging from 0.40 for processed meat to 0.82 for sweets and non-dairy drinks). Cross-classification analysis between the first FFQ and 4DEFD for ranking participants into thirds showed that breakfast cereals had the highest agreement (54.0%) and pasta the lowest (34.0%). In validity analyses, 70% of food items/groups had a SCC ≥0.3. Results indicate that the FFQ is a useful tool for ranking children according to food items/groups intake. The low respondent burden and relative simplicity of the FFQ makes it suitable for use in large cohort studies of 9-10 year-old children in New Zealand.

Electronic Dietary Intake Assessment (e-DIA): relative validity of a mobile phone application to measure intake of food groups

Automation of dietary assessment can reduce limitations of established methodologies, by alleviating participant and researcher burden. Designed as a research tool, the electronic Dietary Intake Assessment (e-DIA) is a food record in mobile phone application format. The present study aimed to examine the relative validity of the e-DIA with the 24-h recall method to estimate intake of food groups. A sample of eighty university students aged 19–24 years recorded 5 d of e-DIA and 3 d of recall within this 5-d period. The three matching days of dietary data were used for analysis. Food intake data were disaggregated and apportioned to one of eight food groups. Median intakes of food groups were similar between the methods, and strong correlations were found (mean: 0·79, range: 0·69–0·88). Cross-classification by tertiles produced a high level of exact agreement (mean: 71 %, range: 65–75 %), and weightedκvalues were moderate to good (range: 0·54–0·71). Although mean differences (e-DIA–recall) were small (range: –13 to 23 g), limits of agreement (LOA) were relatively large (e.g. for vegetables, mean difference: –4 g, LOA: –159 to 151 g). The Bland–Altman plots showed robust agreement, with minimum bias. This analysis supports the use of e-DIA as an alternative to the repeated 24-h recall method for ranking individuals’ food group intake.

Dietary patterns of obese and normal-weight women of reproductive age in urban slum areas in Central Jakarta

Developing countries including Indonesia imperatively require an understanding of factors leading to the emerging problem of obesity, especially within low socio-economic groups, whose dietary pattern may contribute to obesity. In this cross-sectional study, we compared the dietary patterns and food consumption of 103 obese and 104 normal-weight women of reproductive age (19-49 years) in urban slum areas in Central Jakarta. A single 24-h food recall was used to assess energy and macronutrient intakes (carbohydrate, protein and fat) and calculate energy density. A principal component analysis was used to define the dietary patterns from the FFQ. Obese women had significantly higher intakes of energy (8436·6 (sd 2358·1) v. 7504·4 (sd 1887·8) kJ (2016·4 (sd 563·6) v. 1793·6 (sd 451·2) kcal)), carbohydrate (263·9 (sd 77·0) v. 237·6 (sd 63·0) g) and fat (83·11 (sd 31·3) v. 70·2 (sd 26·1) g) compared with normal-weight women; however, their protein intake (59·4 (sd 19·1) v. 55·9 (sd 18·5) g) and energy density (8·911 (sd 2·30) v. 8·58 (sd 1·88) kJ/g (2·13 (sd 0·55) v. 2·05 (sd 0·45) kcal/g)) did not differ significantly. Two dietary patterns were revealed and subjectively named 'more healthy' and 'less healthy'. The 'less healthy' pattern was characterised by the consumption of fried foods (snacks, soyabean and roots and tubers) and meat and poultry products, whereas the more healthy pattern was characterised by the consumption of seafood, vegetables, eggs, milk and milk products and non-fried snacks. Subjects with a high score for the more healthy pattern had a lower obesity risk compared with those with a low score. Thus, obesity is associated with high energy intake and unhealthy dietary patterns characterised by consumption of oils and fats through fried foods and snacks.

Dietary quality varies according to data collection instrument: a comparison between a food frequency questionnaire and 24-hour recall

The objective of this study was to assess the agreement between the Brazilian Healthy Eating Index - Revised (BHEI-R), estimated by a food frequency questionnaire (FFQ) and multiple 24-hour recalls (24h-R). The Wilcoxon paired test, partial correlations (PC), intraclass correlation coefficient (ICC), and Bland-Altman method were used. The total BHEI-R scores and its components ("total fruits", "whole fruits", "total vegetables", "integral cereals", "saturated fat", "sodium", and "energy intake derived from solid fat, added sugar, and alcoholic beverages") were statistically different, with the ICC and PC indicating poor concordance and correlation. The mean concordance estimated for the total BHEI-R and its components varied from 68% for "integral cereals" to 147% for "whole fruits". The suitable concordance limits were violated for most of the components of the BHEI-R. Poor concordance was observed between the BHEI-R estimated by the FFQ and by multiple 24h-R, which indicated a strong reliability of the BHEI-R on the instrument used to collect information on food consumption.

Reproducibility and Validity of a Food Frequency Questionnaire for Assessing Dietary Consumption via the Dietary Pattern Method in a Chinese Rural Population

Objective

This study was conducted to assess the reproducibility and validity of a food frequency questionnaire (FFQ) that was developed to assess the overall dietary consumption via dietary pattern method in a rural population in southwest China.

Methods

A total of 179 participants aged between 40 and 70 years old were included in this study. Participants administered FFQ at baseline (FFQ1) and one year later (FFQ2) to assess the reproducibility. Six 3-day 24-hour recalls (24HRs) were completed between the administrations of two FFQs to determine the validity. Dietary patterns from three separate dietary sources were derived by using principle component factor analysis. Comparisons between dietary pattern scores were made by using Pearson or intraclass correlation coefficient, cross-classification analysis, weighted kappa (κ) statistic and Bland-Altman analysis. The de-attenuated method was adopted to correct the monthly and seasonally variation and the partial correlation analysis was used correct the influence by total energy intake.

Results

Two major dietary factors, labeled as prudent pattern and processed food pattern, were identified. The prudent pattern was characterized by higher factor loadings of wheat, rice, fresh vegetables, bean products, nuts, red meat, white meat and fresh eggs; and the processed food pattern was characterized by higher factor loadings of pickled vegetables, preserved vegetables and salted meat. Between Two FFQs, intraclass correlation coefficients were 0.57 for prudent pattern and 0.55 for processed food pattern, partial Pearson correlation coefficients were 0.51 for the prudent pattern and 0.56 for the processed food pattern; weighted κ statistic ranged from 0.45 (for the prudent pattern) to 0.56 (for the processed food pattern). Between FFQs and 24HRs, de-attenuated correlation coefficients ranged from 0.54 to 0.78 for the prudent pattern and from 0.55 to 0.61 for the processed food pattern; partial Pearson correlation coefficients ranged from 0.41 to 0.56 for the prudent pattern and from 0.42 to 0.44 for the processed food pattern; weighted κ statistic ranged from 0.42 to 0.46 for prudent pattern and from 0.43 to 0.60 for processed food pattern. The Bland-Altman plots and limits of agreement indicated that the deviation/divergence was not obvious for both of the patterns between FFQ1 and FFQ2 and between FFQs and 24HRs.

Conclusion

The study suggests that the FFQ is reasonably reproducible and valid to assess the overall dietary consumption via dietary pattern methods in the Chinese rural population.

[Dietary patterns of children and socioeconomical, behavioral and maternal determinants]

Objective:

To identify dietary patterns of children and to verify their association with socio-economical, behavioral and maternal determinants.

Methods:

A cross-sectional study with a random sample of 328 children aged 8 and 9 years. Dietary intake was assessed by food records in three nonconsecutive days and measured in grams of food groups and nutrients. Factor analysis and subsequent orthogonal rotation (varimax) were used to determine dietary patterns. Ordinal logistic regression was used to assess associations between dietary patterns and the studied determinants.

Results:

Five dietary patterns were observed: “Traditional,” “Sweetened beverages and snacks,” “Monotonous,” “Healthy” and “Egg-dairy.” A higher maternal level of education was directly associated with “Sweetened beverages and snacks” and “Egg-dairy' standards. Low income children who were submitted to greater food restriction by parents/guardians followed the more “Traditional” standard, represented by the consumption of rice, beans, vegetables, cooked roots and tubers and red meat. The “Monotonous” pattern, represented by a high consumption of milk and chocolate powder, was most followed by children from the middle class. Children living in rural areas consumed more foods from the “Egg-dairy” pattern, when compared to those from the urban area.

Conclusions:

Dietary patterns of children were associated with family socioeconomic status, maternal level of education, practice of food restriction by parents/guardians and location of residence in urban or rural area. Better socioeconomic conditions contributed to a more nutritionally inadequate dietary pattern.

Glycemic modulation in neuro-oncology: experience and future directions using a modified Atkins diet for high-grade brain tumors

Dietary glycemic modulation through high-fat, low-carbohydrate diets, which induce a state of systemic ketosis and alter systemic metabolic signaling, have been incorporated into the clinical management of patients with neurological disease for more than a century. Mounting preclinical evidence supports the antitumor, proapoptotic, and antiangiogenic effects of disrupting glycolytic metabolism through dietary intervention. In recent years, interest in incorporating such novel therapeutic strategies in neuro-oncology has increased. To date, 3 published studies incorporating novel dietary therapies in oncology have been reported, including one phase I study in neuro-oncology, and have set the stage for further study in this field. In this article, we review the biochemical pathways, preclinical data, and early clinical translation of dietary interventions that modulate systemic glycolytic metabolism in the management of primary malignant brain tumors. We introduce the modified Atkins diet (MAD), a novel dietary alternative to the classic ketogenic diet, and discuss the critical issues facing future study.

A Western dietary pattern is associated with poor academic performance in Australian adolescents

The aim of this study was to investigate cross-sectional associations between dietary patterns and academic performance among 14-year-old adolescents. Study participants were from the Western Australian Pregnancy Cohort (Raine) Study. A food frequency questionnaire was administered when the adolescents were 14 years old, and from the dietary data, a 'Healthy' and a 'Western' dietary pattern were identified by factor analysis. The Western Australian Literacy and Numeracy Assessment (WALNA) results from grade nine (age 14) were linked to the Raine Study data by The Western Australian Data Linkage Branch. Associations between the dietary patterns and the WALNA (mathematics, reading and writing scores) were assessed using multivariate linear regression models adjusting for family and socioeconomic characteristics. Complete data on dietary patterns, academic performance and covariates were available for individuals across the different analyses as follows: n = 779 for mathematics, n = 741 for reading and n = 470 for writing. Following adjustment, significant negative associations between the 'Western' dietary pattern and test scores for mathematics (β = -13.14; 95% CI: -24.57; -1.76); p = 0.024) and reading (β = -19.16; 95% CI: -29.85; -8.47; p ≤ 0.001) were observed. A similar trend was found with respect to writing (β = -17.28; 95% CI: -35.74; 1.18; p = 0.066). ANOVA showed significant trends in estimated means of academic scores across quartiles for both the Western and Healthy patterns. Higher scores for the 'Western' dietary pattern are associated with poorer academic performance in adolescence.

Relative validity and reproducibility of a food frequency questionnaire for identifying the dietary patterns of toddlers in New Zealand

BACKGROUND

Dietary patterns provide insight into relationships between diet and disease. Food frequency questionnaires (FFQs) can identify dietary patterns in adults, but similar analyses have not been performed for toddlers.

OBJECTIVE

The aim of the Eating Assessment in Toddlers study was to evaluate the relative validity and reproducibility of dietary patterns from an FFQ developed for toddlers aged 12 to 24 months.

DESIGN/SETTING

Participants were 160 toddlers aged 12 to 24 months and their primary caregiver who completed an FFQ twice, approximately 5 weeks apart (FFQ1 and FFQ2). A 5-day weighed food record was collected on nonconsecutive days between FFQ administrations.

STATISTICAL ANALYSIS

Principal component analysis identified three major dietary patterns similar across FFQ1, FFQ2, and the 5-day weighted food record.

RESULTS

The sweet foods and fries pattern was characterized by high intakes of sweet foods, fries and roast potato and kumara (sweet potato), butter and margarines, processed meat, sweet drinks, and fruit or milk drinks. The vegetables and meat pattern was characterized by high intakes of vegetables, meat, eggs and beans, and fruit. The milk and fruit pattern was characterized by high intakes of milk and milk products and fruit, and low intakes of breastmilk and infant and follow-up formula. The FFQ (FFQ1) correctly classified 43.1% to 51.0% of toddlers into the same quartile of pattern score as the 5-day weighted food record, and Pearson correlations ranged from 0.56 to 0.68 for the three patterns. Reliability coefficients ranged from 0.71 to 0.72 for all three dietary patterns.

CONCLUSIONS

the Eating Assessment in Toddlers study FFQ shows acceptable relative validity and high reproducibility for identifying dietary patterns in toddlers.

The reliability of an adolescent dietary pattern identified using reduced-rank regression: comparison of a FFQ and 3 d food record

Despite the increasing use of dietary patterns (DP) to study diet and health outcomes, relatively few studies have examined the reliability of DP using different dietary assessment methods. Reduced-rank regression (RRR) is an emerging statistical method that incorporates a priori information to characterise DP related to specific outcomes of interest. The aim of the present study was to compare DP identified using the RRR method in a FFQ with those in a 3 d food record (FR). Participants were 783 adolescents from the Western Australian Pregnancy (Raine) Cohort Study who completed both a FFQ and FR at 14 years of age. A similar 'energy-dense, high-fat and low-fibre' DP was identified in the FFQ and FR that was characterised by high intakes of processed meat and sugar-sweetened beverages, and low intakes of vegetables and fresh fruit. Nutrient profiles for this DP were consistent in the FFQ and FR. Pearson's correlation coefficient between participants' z-scores for the DP identified in the FFQ and FR was 0·35 for girls and 0·49 for boys (P< 0·05). The mean difference between DP z-scores derived from the FFQ and FR was -0·08 (95 % CI -0·21, 0·04) for girls and -0·05 (95 % CI -0·17, 0·07) for boys. The 95 % limits of agreement were -2·55 to 2·39 for girls and -2·52 to 2·41 for boys. These findings suggest that very similar DP may be identified and their z-scores show modest agreement when applying the RRR method to dietary intake data collected from adolescents using a FFQ or FR.

Dairy product consumption, dietary nutrient and energy density and associations with obesity in Australian adolescents

BACKGROUND

Dairy intake is likely to influence dietary energy density (ED) and nutrient density (ND), which are factors representing aspects of dietary quality. Although evidence suggests dairy intake is unlikely to contribute to obesity, intake tends to decrease over adolescence, potentially as a result of concerns around weight gain. We examined associations between dairy intake, ED and ND, and investigated relationships with obesity in adolescents.

METHODS

The present study comprised a cross-sectional study of 1613 14-year-olds in the Western Australian Pregnancy Cohort (Raine) Study. Adolescents completed a 212-item food frequency questionnaire. Nutrient Rich Food index 9.3 (NRF9.3) was used to estimate ND. Age-specific body mass index (BMI) and waist-height cut-offs were used to categorise obesity risk.

RESULTS

Mean (SD) dairy intake was: 2.62 (1.51) servings daily; ED was 4.53 (0.83) (food and beverage) and 6.28 (1.33) (food only); ND was 373 (109). Dairy intake was inversely associated with ED and positively associated with ND. The odds of being overweight (as assessed by BMI) increased by 1.24 (95% confidence interval = 1.09-1.42) with each 100-point increase in ND, after adjustment for potential confounders and energy intake. ED measures and dairy intake were inversely associated with obesity after adjustment for confounders; associations became nonsignificant after energy adjustment.

CONCLUSIONS

The NRF9.3 was originally designed to assess foods, not diets. Further research in other cohorts to determine whether similar findings exist, or investigations into alternate measures of dietary ND, may prove useful. Our findings may be the result of factors such as an excess consumption of refined but fortified foods. Although higher dairy intakes were associated with higher ND, intakes were not associated with higher obesity risk.

Dietary patterns in UK adolescents obtained from a dual-source FFQ and their associations with socio-economic position, nutrient intake and modes of eating

OBJECTIVE

To derive dietary patterns using principal components analysis from separate FFQ completed by mothers and their teenagers and to assess associations with nutrient intakes and sociodemographic variables.

DESIGN

Two distinct FFQ were completed by 13-year-olds and their mothers, with some overlap in the foods covered. A combined data set was obtained.

SETTING

Avon Longitudinal Study of Parents and Children (ALSPAC), Bristol, UK.

SUBJECTS

Teenagers (n 5334) with adequate dietary data.

RESULTS

Four patterns were obtained using principal components analysis: a 'Traditional/health-conscious' pattern, a 'Processed' pattern, a 'Snacks/sugared drinks' pattern and a 'Vegetarian' pattern. The 'Traditional/health-conscious' pattern was the most nutrient-rich, having high positive correlations with many nutrients. The 'Processed' and 'Snacks/sugared drinks' patterns showed little association with important nutrients but were positively associated with energy, fats and sugars. There were clear gender and sociodemographic differences across the patterns. Lower scores were seen on the 'Traditional/health conscious' and 'Vegetarian' patterns in males and in those with younger and less educated mothers. Higher scores were seen on the 'Traditional/health-conscious' and 'Vegetarian' patterns in girls and in those whose mothers had higher levels of education.

CONCLUSIONS

It is important to establish healthy eating patterns by the teenage years. However, this is a time when it is difficult to accurately establish dietary intake from a single source, since teenagers consume increasing amounts of foods outside the home. Further dietary pattern studies should focus on teenagers and the source of dietary data collection merits consideration.

Dietary patterns within a population are more reproducible than those of individuals

Insight into the stability of dietary behavior over time is important, because only a single measurement of diet is often available to study the association between eating behavior and the occurrence of chronic diseases many years after baseline data collection. Little is known about changes in dietary patterns over time. The current study examined the (internal) stability and reproducibility of dietary patterns and the transition of individuals between patterns over time from 3 surveys within one study population by using cluster analysis. The dietary intake of participants in the Doetinchem Cohort Study in 6113, 4916, and 4520 adults in 1993-1997, 1998-2002, and 2003-2007, respectively, was measured using a validated food-frequency questionnaire. Stability and reproducibility of dietary patterns were studied by examining the optimal number of clusters per survey by comparing the contribution of food groups to total energy intake within the clusters over time and by studying transitions of individuals between clusters over time. A low-fiber bread pattern and a high-fiber bread pattern were identified in all 3 surveys. Over time, dietary patterns were comparable in terms of foods contributing most to total energy intake, suggesting good reproducibility. Nevertheless, only 41.8% of the participants were consistently assigned to the same dietary pattern for all 3 surveys. This implies that, over time, similar dietary patterns were found at the group level, but that ignoring individual transitions between dietary patterns during follow-up may lead to misclassification of a large proportion of the study population.

Eating patterns and mental health problems in early adolescence--a cross-sectional study of 12-13-year-old Norwegian schoolchildren

OBJECTIVE

To investigate the association between eating patterns and mental health problems in young Norwegian adolescents (12-13 years of age).

DESIGN

Cross-sectional study. Dietary information was reported by parents using a retrospective FFQ. Eating patterns were identified using principal component analysis. The Strengths and Difficulties Questionnaire was used to measure mental health problems. The association between eating patterns and mental health problems was examined using multiple logistic regression analysis.

SETTING

Primary schools, Telemark County, Norway.

SUBJECTS

Children (n 1095) aged 12-13 years and their parents.

RESULTS

Children with high scores on a 'varied Norwegian' eating pattern were less likely to have indications of any psychiatric disorders (adjusted OR = 0·5; 95 % CI 0·3, 1·0) and hyperactivity-inattention disorders (adjusted OR = 0·4; 95 % CI 0·2, 0·8) than children with low scores on this pattern. Children with high scores on a 'junk/convenient' eating pattern were more likely to have indications of hyperactivity-inattention disorders (adjusted OR = 3·4; 95 % CI 1·3, 8·6) than children with low scores on this pattern. Children with high scores on a 'snacking' eating pattern were more likely to have indications of conduct/oppositional disorders (adjusted OR = 3·8; 95 % CI 1·2, 11·5) than those with low scores on this eating pattern.

CONCLUSIONS

We identified a significant association between eating patterns and mental health problems in young adolescents, independently of physical activity, sedentary activity and background variables. A diverse diet rich in unrefined plant foods, fish and regular meals was associated with better mental health, while energy-dense, nutrient-poor diets and irregular meals were associated with poorer mental health.

The Western dietary pattern is prospectively associated with nonalcoholic fatty liver disease in adolescence

OBJECTIVES

Poor dietary habits have been implicated in the development of nonalcoholic fatty liver disease (NAFLD); however, little is known about the role of specific dietary patterns in the development of NAFLD. We examined prospective associations between dietary patterns and NAFLD in a population-based cohort of adolescents.

METHODS

Participants in the Western Australian Pregnancy Cohort (Raine) Study completed a food frequency questionnaire at 14 years and had liver ultrasound at 17 years (n=995). Healthy and Western dietary patterns were identified using factor analysis and all participants received a z-score for these patterns. Prospective associations between the dietary pattern scores and risk of NAFLD were analyzed using multiple logistic regression.

RESULTS

NAFLD was present in 15.2% of adolescents. A higher Western dietary pattern score at 14 years was associated with a greater risk of NAFLD at 17 years (odds ratio (OR) 1.59; 95% confidence interval (CI) 1.17-2.14; P<0.005), although these associations were no longer significant after adjusting for body mass index at 14 years. However, a healthy dietary pattern at 14 years appeared protective against NAFLD at 17 years in centrally obese adolescents (OR 0.63; 95% CI 0.41-0.96; P=0.033), whereas a Western dietary pattern was associated with an increased risk of NAFLD.

CONCLUSIONS

A Western dietary pattern at 14 years in a general population sample was associated with an increased risk of NAFLD at 17 years, particularly in obese adolescents. In centrally obese adolescents with NAFLD, a healthy dietary pattern may be protective, whereas a Western dietary pattern may increase the risk.

Relative validity of dietary patterns during pregnancy assessed with a food frequency questionnaire

This study aimed to assess the relative validity of maternal dietary patterns derived from a semi-quantitative food frequency questionnaire (FFQ). A total of 162 pregnant women aged 19-40-years-old were enrolled from the Universiti Sains Malaysia (USM) Birth Cohort Study in year 2010 and 2011. The FFQ was compared with three 24-h dietary recalls (DRs). Two major dietary patterns were derived from the principle component analysis which are labeled as Healthy and Less-Healthy patterns. The Pearson correlation coefficients between FFQ and DRs for Healthy and Less-Healthy patterns were 0.59 and 0.63, respectively. At least 45% of the participants were correctly classified into the same third from the FFQ and DR for both dietary patterns. The weighted kappa showed moderate agreement for Healthy pattern while good agreement for Less-Healthy pattern between these two dietary assessment methods. Our results indicate reasonable validity of the dietary patterns identified from the FFQ in pregnant women.

Changes in dairy food and nutrient intakes in Australian adolescents

Dairy nutrients, such as calcium, are particularly important in adolescence, a critical time for growth and development. There are limited Australian data following individuals through adolescence, evaluating changes in dairy nutrient and dairy product consumption. We used a validated food frequency questionnaire to investigate consumption in adolescents participating in both the 14 and 17 year follow-ups of the Western Australian Pregnancy Cohort (Raine) Study. Most adolescents did not reach age and gender specific recommended daily intakes for calcium or magnesium at 14 years, and this decreased as they aged to 17 years (from 33.0% to 29.2% meeting for calcium, P < 0.05, and from 33.6% to 20.5% meeting for magnesium, P < 0.01). Mean intakes of calcium, potassium, riboflavin and vitamin A also decreased with age (P < 0.01). Mean dairy intake decreased from 536 ± 343 g/day to 464 ± 339 g/day (P < 0.01), due mostly to a decrease in regular milk, although flavoured milk consumption increased in boys. Cheese and butter were the only products to show a significantly increased consumption over the period. Girls decreased from 2.2 to 1.9 serves/day of dairy, while boys remained relatively steady at 2.9 to 2.8 serves/day. Our findings suggest that dairy product consumption decreases over adolescence. This may have implications for bone mass, development and later health.

The relative validity and reproducibility of an iron food frequency questionnaire for identifying iron-related dietary patterns in young women

BACKGROUND

Using food frequency data to identify dietary patterns is a newly emerging approach to assessing the relationship between dietary intake and iron status. Food frequency questionnaires should be assessed for validity and reproducibility before use.

OBJECTIVE

We aimed to investigate the relative validity and reproducibility of an iron food frequency questionnaire (FeFFQ) specifically designed to identify iron-related dietary patterns.

DESIGN

Participants completed the FeFFQ at baseline (FeFFQ1) and 1 month later (FeFFQ2) to assess reproducibility. A 4-day weighed diet record (4DDR) was completed between these assessments to determine validity. Foods appearing in the 4DDR were classified into the same 144 food groupings as the FeFFQ. Factor analysis was used to determine dietary patterns from FeFFQ1, FeFFQ2, and the 4DDR.

PARTICIPANTS/SETTING

A convenience sample of women (n=115) aged 18 to 44 years living in Auckland, New Zealand, during 2009.

STATISTICAL ANALYSES PERFORMED

Agreement between diet pattern scores was compared using correlation coefficients, Bland-Altman analysis, cross-classification, and the weighted κ statistic.

RESULTS

A "healthy" and a "sandwich and drinks" dietary pattern were identified from all three dietary assessments. Correlation coefficients between FeFFQ1 and the 4DDR diet pattern scores (validity) were 0.34 for the healthy, and 0.62 for the sandwich and drinks pattern (both Ps<0.001). Correlation coefficients between the two FeFFQs (reproducibility) were 0.76 for both the healthy and sandwich and drinks pattern (P<0.001). The FeFFQ1 correctly classified >50% of participants into the correct tertile and <10% into the opposite tertile for both the healthy and sandwich and drinks diet pattern scores when compared with the 4DDR and FeFFQ2.

CONCLUSIONS

The FeFFQ appears to be a reproducible and relatively valid method for identifying dietary patterns, and could be used to investigate the relationship between dietary patterns and iron status.

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.

Reliability, comparative validity and stability of dietary patterns derived from an FFQ in the Tehran Lipid and Glucose Study

The aim of the present study was to assess the reliability, comparative validity and stability of dietary patterns defined by factor analysis for participants of the Tehran Lipid and Glucose Study. A total of 132 subjects, aged ≥ 20 years, completed a 168-item FFQ (FFQ1, FFQ2) twice, with a 14-month interval. Over this duration, twelve dietary recalls (DR) were collected each month. To assess the stability of the FFQ, participants completed the third FFQ (FFQ3) after 8 years. Following these, two dietary patterns--the 'Iranian Traditional' and the 'Western'--were derived from FFQ1 and FFQ2 and the mean of DR (mDR); and three dietary patterns were identified from FFQ3: the 'Iranian Traditional', the 'Western' and the 'Combined'. The reliability correlations between factor scores of the two FFQ were 0·72 for the Iranian Traditional and 0·80 for the Western pattern; corrected month-to-month variations of DR correlations between the FFQ2 and mDR were 0·48 for the first and 0·75 for the second pattern. The 95 % limits of agreement for the difference between factor scores obtained from FFQ2 and mDR lay between -1·58 and +1·58 for the Iranian Traditional and between -1·33 and +1·33 for the Western pattern. The intra-class correlations between FFQ2 and FFQ3 were -0·09 (P = 0·653) and 0·49 (P <0·001) for the 'Iranian Traditional' and the 'Western', respectively. These data indicate reasonable reliability and validity of the dietary patterns defined by factor analysis. Although the Western pattern was found to be fairly stable, the Iranian Traditional pattern was mostly unstable over the 8 years of the study period.

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.

Efficacy of a compulsory homework programme for increasing physical activity and healthy eating in children: the healthy homework pilot study

BACKGROUND

Most physical activity and nutrition interventions in children focus on the school setting; however, evidence suggests that children are less active and have greater access to unhealthy food at home. The aim of this pilot study was to examine the efficacy of a compulsory homework programme for increasing physical activity and healthy eating in children.

METHODS

The six-week 'Healthy Homework' programme and complementary teaching resource was developed under the guidance of an intersectoral steering group. Eight senior classes (year levels 5-6) from two diverse Auckland primary schools were randomly assigned into intervention and control groups. A total of 97 children (57 intervention, 40 control) aged 9-11 years participated in the evaluation of the intervention. Daily step counts were monitored immediately before and after the intervention using sealed multiday memory pedometers. Screen time, sports participation, active transport to and from school, and the consumption of fruits, vegetables, unhealthy foods and drinks were recorded concurrently in a 4-day food and activity diary.

RESULTS

Healthy Homework resulted in a significant intervention effect of 2,830 steps.day-1 (95% CI: 560, 5,300, P = 0.013). This effect was consistent between sexes, schools, and day types (weekdays and weekend days). In addition, significant intervention effects were observed for vegetable consumption (0.83 servings.day-1, 95% CI: 0.24, 1.43, P = 0.007) and unhealthy food consumption (-0.56 servings.day-1, 95% CI: -1.05, -0.07, P = 0.027) on weekends but not weekdays, with no interactions with sex or school. Effects for all other variables were not statistically significant regardless of day type.

CONCLUSIONS

Compulsory health-related homework appears to be an effective approach for increasing physical activity and improving vegetable and unhealthy food consumption in children. Further research in a larger study is required to confirm these initial results.

Omega-3 Index correlates with healthier food consumption in adolescents and with reduced cardiovascular disease risk factors in adolescent boys

The Omega-3 Index, a measure of long-chain omega-3 fats in red blood cell membranes, predicts heart disease mortality in adults, but its association with cardiovascular risk factors in younger populations is unknown. We determined the Omega-3 Index in adolescents participating in the Western Australian Pregnancy (Raine) Cohort, assessed associations with diet, lifestyle and socioeconomic factors, and investigated independent associations with cardiovascular and metabolic risk factors. Red blood cell fatty acid analysis was determined for 1,301 adolescents aged 13-15 years. Risk factors examined were blood pressure, fasting blood insulin and glucose concentrations, and fasting blood lipids including ratios. The mean Omega-3 Index was 4.90 ± 1.04% (range 1.41-8.42%). When compared with categories identified in adults, 15.6% of adolescents were in the high risk category (Index < 4%). Age (P < 0.01), maternal education (P < 0.01) and BMI (P = 0.05) were positively associated with the Omega-3 Index. The Index was positively associated with dietary intakes of eicosapentaenoic and docosahexaenoic acid (P < 0.01), protein (P < 0.01), omega-3 fats (P < 0.04), and food groups of fish and wholegrains (both P < 0.01), and negatively associated with intakes of soft drinks and crisps (both P < 0.01). In boys, the Omega-3 Index was independently associated with total (β = 0.06, P = 0.01) and HDL-cholesterol (β = 0.03, P = 0.01), and diastolic blood pressure (β = -0.68, P = 0.04). The predictability of the Index for the risk of cardiovascular disease later in life warrants further investigation in the adolescent population.