Rebecca M. Leech

Characterizing eating patterns: a comparison of eating occasion definitions

BACKGROUND To date, many approaches have been used to define eating occasions (EOs). A standard definition for EOs is required to facilitate further research. OBJECTIVE In this study, we examined the influence of differing definitions of EOs on the characterization of eating patterns. DESIGN Cross-sectional dietary data from two 24-h recalls collected during the 2011-12 Australian National Nutrition and Physical Activity Survey (n = 5242 adults, aged ≥19 y) were analyzed. Eight definitions were applied: participant-identified, time-of-day, and 6 neutral definitions (individual EOs separated by different time intervals and/or an additional energy criterion of 210 kJ). Frequency of and total energy intake from meals, snacks, and all EOs were estimated, as appropriate. Differences were tested by using F tests, stratified by sex and age group. Agreement between different definitions of meal and snack frequencies was assessed by using intraclass correlation coefficients (ICCs). For each definition, linear regression was used to estimate the proportion of variance in total energy intake (kJ) and amount of food intake (g) predicted by frequency of EOs and meals and snacks. RESULTS Among both sexes and across all age groups, mean frequencies of meals differed between the participant-identified and time-of-day definitions (mean difference range = 0.1-0.3; P < 0.001). There were statistically significant differences between mean frequencies of EOs across the 6 neutral definitions (P < 0.001). There was good agreement for snacks (men: ICC = 0.89; women: ICC = 0.87) but not meal frequencies (men: ICC = 0.38; women: ICC = 0.36) between the participant-identified and time-of-day definitions. The neutral definition (15-min time interval plus energy criterion) best predicted variance in total energy intake (R(2) range = 19.3-27.8). CONCLUSIONS Different approaches to the definition of EOs affect how eating patterns are characterized, with the neutral definition best predicting variance in total energy intake. Further research that examines how different EO definitions affect associations with health outcomes is needed to develop consensus on a standard EO definition.

Is the relationship between sedentary behaviour and cardiometabolic health in adolescents independent of dietary intake? A systematic review

Screen time, but not overall sedentary behaviour, is consistently related to cardiometabolic health in adolescents. Because of the associations screen time has with dietary intake, diet may be an important factor in the screen time and health relationship; however, evidence has not previously been synthesized. Thus, the aim of this systematic review was to explore whether the associations between various sedentary behaviours and cardiometabolic risk markers are independent of dietary intake in adolescents. Online databases and personal libraries were searched for peer‐reviewed original research articles published in English before March 2014. Included studies assessed associations between sedentary behaviour and cardiometabolic markers in 12‐ to 18‐year‐olds and adjusted for dietary intake. Twenty‐five studies met the inclusion criteria. From the 21 studies examining sedentary behaviour and adiposity, the majority found significant positive associations between television viewing, screen time and self‐reported overall sedentary behaviour with markers of adiposity, independent of dietary intake. No significant associations between screen time with blood pressure and cholesterol were reported. Sedentary behaviour appears to be associated with adiposity in adolescents, irrespective of dietary intake. However, the variability of dietary variables between studies suggests further work is needed to understand the role of dietary intake when examining these associations in youth.

Family food involvement and frequency of family dinner meals among Australian children aged 10-12years. Cross-sectional and longitudinal associations with dietary patterns.

Involvement in meal preparation and eating meals with the family are associated with better dietary patterns in adolescents, however little research has included older children or longitudinal study designs. This 3-year longitudinal study examines cross-sectional and longitudinal associations between family food involvement, family dinner meal frequency and dietary patterns during late childhood. Questionnaires were completed by parents of 188 children from Greater Melbourne, Australia at baseline in 2002 (mean age=11.25years) and at follow-up in 2006 (mean age=14.16years). Principal components analysis (PCA) was used to identify dietary patterns. Factor analysis (FA) was used to determine the principal factors from six indicators of family food involvement. Multiple linear regression models were used to predict the dietary patterns of children and adolescents at baseline and at follow-up, 3years later, from baseline indicators of family food involvement and frequency of family dinner meals. PCA revealed two dietary patterns, labeled a healthful pattern and an energy-dense pattern. FA revealed one factor for family food involvement. Cross-sectionally among boys, family food involvement score (β=0.55, 95% CI: 0.02, 1.07) and eating family dinner meals daily (β=1.11, 95% CI: 0.27, 1.96) during late childhood were positively associated with the healthful pattern. Eating family dinner meals daily was inversely associated with the energy-dense pattern, cross-sectionally among boys (β=-0.56, 95% CI: -1.06, -0.06). No significant cross-sectional associations were found among girls and no significant longitudinal associations were found for either gender. Involvement in family food and eating dinner with the family during late childhood may have a positive influence on dietary patterns of boys. No evidence was found to suggest the effects on dietary patterns persist into adolescence.

Clustering of children’s obesity-related behaviours: associations with sociodemographic indicators

Background/objectives:Research suggests obesity-related behaviours cluster together in children and adolescents, but how these cluster patterns differ by sociodemographic indicators remains unclear. Furthermore, few studies examining clustering of behaviours have included younger children or an objective measure of physical activity (PA) and sedentary behaviour. Therefore, the aim of this study was to examine clustering patterns of diet, PA and sedentary behaviour in 5- to 6- and 10- to 12-year-old children, and their cross-sectional associations with sociodemographic indicators.Subjects/methods:In this cross-sectional study, data from the baseline wave (2002/2003) of the Health Eating and Play study (HEAPS) were used. Questionnaires were completed by parents of Australian children aged 5–6 (n=362) and 10–12 years (n=610). Children wore accelerometers for up to 7 days. K-medians cluster analysis identified groups of children with similar diet, PA and sedentary behaviours. Chi-square tests assessed cluster differences by gender, maternal education and marital status.Results:For each age group, three reliable and meaningful clusters were identified and labelled ‘most healthy’, ‘energy-dense (ED) consumers who watch TV’ and ‘high sedentary behaviour/low moderate-to-vigorous PA (MVPA)’. Clusters varied by sociodemographic indicators. For example, a higher proportion of older girls comprised the ‘high sedentary behaviour/low MVPA’ cluster (χ2=22.4, P<0.001). Among both age groups, the ‘ED consumers who watch TV’ cluster comprised more children with lower educated mothers (younger children: χ2=34.9, P<0.001; older children: χ2=27.3, P<0.001).Conclusions:Identification of cluster patterns of obesity-related risk factors in children, and across sociodemographic groups may assist the targeting of public health initiatives, to those most in need.

Clustering of diet, physical activity and sedentary behaviour among Australian children: cross-sectional and longitudinal associations with overweight and obesity

Background/Objectives:Evidence suggests diet, physical activity (PA) and sedentary behaviour cluster together in children, but research supporting an association with overweight/obesity is equivocal. Furthermore, the stability of clusters over time is unknown. The aim of this study was to examine the clustering of diet, PA and sedentary behaviour in Australian children and cross-sectional and longitudinal associations with overweight/obesity. Stability of obesity-related clusters over 3 years was also examined.Subjects/Methods:Data were drawn from the baseline (T1: 2002/2003) and follow-up waves (T2: 2005/2006) of the Health Eating and Play Study. Parents of Australian children aged 5–6 (n=87) and 10–12 years (n=123) completed questionnaires. Children wore accelerometers and height and weight were measured. Obesity-related clusters were determined using K-medians cluster analysis. Multivariate regression models assessed cross-sectional and longitudinal associations between cluster membership, and body mass index (BMI) Z-score and weight status. Kappa statistics assessed cluster stability over time.Results:Three clusters, labelled ‘most healthy’, ‘energy-dense (ED) consumers who watch TV’ and ‘high sedentary behaviour/low moderate-to-vigorous PA’ were identified at baseline and at follow-up. No cross-sectional associations were found between cluster membership, and BMI Z-score or weight status at baseline. Longitudinally, children in the ‘ED consumers who watch TV’ cluster had a higher odds of being overweight/obese at follow-up (odds ratio=2.8; 95% confidence interval: 1.1, 6.9; P<0.05). Tracking of cluster membership was fair to moderate in younger (K=0.24; P=0.0001) and older children (K=0.46; P<0.0001).Conclusions:This study identified an unhealthy cluster of TV viewing with ED food/drink consumption, which predicted overweight/obesity in a small longitudinal sample of Australian children. Cluster stability was fair to moderate over 3 years and is a novel finding. Prospective research in larger samples is needed to examine how obesity-related clusters track over time and influence the development of overweight and obesity.

The role of energy intake and energy misreporting in the associations between eating patterns and adiposity

Background/Objectives:Research examining associations between eating occasion (EO) frequency and adiposity is inconclusive; studies examining the impact of energy misreporting are rare. This study examined associations between eating patterns and adiposity, with adjustment for energy misreporting, in a nationally representative sample of Australian adults.Subjects/Methods:Dietary intake was assessed via two 24-h recalls collected during the 2011–12 National Nutrition and Physical Activity Survey (n=4050 adults, aged ⩾19 years). Frequencies of all EOs, meals and snacks were calculated. Height, weight and waist circumference (WC) were measured. Energy misreporting was assessed as the ratio of energy intake to predicted energy expenditure (EI:EE). Energy misreporters were identified by EI:EE ratios, <0.68 or >1.32. Multivariate regression models assessed associations between eating patterns and body mass index (BMI), WC, overweight/obesity (BMI ⩾25 kg m−2) and central overweight/obesity (WC ⩾94 cm in men and ⩾80 cm in women).Results:After adjustment for covariates and EI:EE, frequency of all EOs, meals (women only) and snacks was positively associated with WC and BMI (all P<0.01). Snack, but not meal frequency, was also associated with overweight/obesity (men: OR=1.22, 95% CI 1.07–1.39; women: OR=1.26, 95% CI 1.10–1.43) and central overweight/obesity (men: OR=1.17, 95% CI 1.04–1.32; women: OR=1.21, 95% CI 1.06–1.37). Multivariate analysis that excluded energy misreporters and adjusted for EI yielded either null or inverse associations (P<0.05).Conclusions:These findings suggest that the associations between eating patterns and adiposity are complicated by the role of EI and energy misreporting. Longitudinal research that considers the impact of EI and energy misreporting is needed to better understand the relationship between eating patterns and obesity.

Socioeconomic Inequities in Diet Quality and Nutrient Intakes among Australian Adults: Findings from a Nationally Representative Cross-Sectional Study

Poor diet may represent one pathway through which lower socioeconomic position (SEP) leads to adverse health outcomes. This study examined the associations between SEP and diet quality, its components, energy, and nutrients in a nationally representative sample of Australians. Dietary data from two 24-h recalls collected during the cross-sectional Australian Health Survey 2011-13 (n = 4875; aged ≥ 19 years) were analysed. Diet quality was evaluated using the Dietary Guidelines Index (DGI). SEP was assessed by index of area-level socioeconomic disadvantage, education level, and household income. Linear regression analyses investigated the associations between measures of SEP and dietary intakes. Across all of the SEP indicators, compared with the least disadvantaged group, the most disadvantaged group had 2.5–4.5 units lower DGI. A greater area-level disadvantage was associated with higher carbohydrate and total sugars intake. Lower education was associated with higher trans fat, carbohydrate, and total sugars intake and lower poly-unsaturated fat and fibre intake. Lower income was associated with lower total energy and protein intake and higher carbohydrate and trans fat intake. Lower SEP was generally associated with poorer diet quality and nutrient intakes, highlighting dietary inequities among Australian adults, and a need to develop policy that addresses these inequities.

Are dietary inequalities among Australian adults changing? a nationally representative analysis of dietary change according to socioeconomic position between 1995 and 2011–13

BackgroundIncreasing inequalities in rates of obesity and chronic disease may be partly fuelled by increasing dietary inequalities, however very few nationally representative analyses of socioeconomic trends in dietary inequalities exist. The release of the 2011–13 Australian National Nutrition and Physical Activity Survey data allows investigation of change in dietary intake according to socioeconomic position (SEP) in Australia using a large, nationally representative sample, compared to the previous national survey in 1995. This study examined change in dietary intakes of energy, macronutrients, fiber, fruits and vegetables among Australian adults between 1995 and 2011–13, according to SEP.MethodsCross-sectional data were obtained from the 1995 National Nutrition Survey, and the 2011–13 National Nutrition and Physical Activity Survey. Dietary intake data were collected via a 24-h dietary recall (n = 17,484 adults) and a dietary questionnaire (n = 15,287 adults). SEP was assessed according to educational level, equivalized household income, and area-level disadvantage. Survey-weighted linear and logistic regression models, adjusted for age, sex/gender and smoking status, examined change in dietary intakes over time.ResultsDietary intakes remained poor across the SEP spectrum in both surveys, as evidenced by high consumption of saturated fat and total sugars, and low fiber, fruit and vegetable intakes. There was consistent evidence (i.e. according to ≥2 SEP measures) of more favorable changes in dietary intakes of carbohydrate, polyunsaturated and monounsaturated fat in higher, relative to lower SEP groups, particularly in women. Intakes of energy, total fat, saturated fat and fruit differed over time according to a single SEP measure (i.e. educational level, household income, or area-level disadvantage). There were no changes in intake of total sugars, protein, fiber or vegetables according to any SEP measures.ConclusionsThere were few changes in dietary intakes of energy, most macronutrients, fiber, fruits and vegetables in Australian adults between 1995 and 2011–13 according to SEP. For carbohydrate, polyunsaturated and monounsaturated fat, more favorable changes in intakes occurred in higher SEP groups. Despite the persistence of suboptimal dietary intakes, limited evidence of widening dietary inequalities is positive from a public health perspective.Trial registrationClinical trials registration: ACTRN12617001045303.

Novel online or mobile methods to assess eating patterns

Purpose of ReviewRecent developments in technology-based dietary assessment allow real-time data collection of eating occasions, yet their application to assessing eating pattern constructs has not been evaluated. The purpose of this review was to examine existing electronic and mobile food diary methods in relation to their ability to assess eating patterns constructs (e.g. patterning, format and context of eating occasions).Recent FindingsA systematic search of electronic databases identified 18 dietary assessment methods. Multiple methods with diverse technological capabilities have been developed, yet few studies report on their ability to assess all eating pattern constructs, particularly eating occasion context. Validity of the methods to assess overall dietary intake was found to be similar to traditional dietary assessment methods.SummaryA diverse range of methods are available for examining the patterning and format/content, but not context, of eating occasions. Further consideration of eating pattern constructs is required when developing dietary assessment methods.