Energy density of the diet and change in body fatness from childhood to adolescence; is there a relation?

Dietary Energy Density Is Associated with Biomarkers of Chronic Diseases-A Cross-Sectional Study of School-Aged Children in Rural Mexico

Background

Dietary energy density (DED) is associated with chronic disease markers in adults. However, results in children are still controversial.

Objective

To evaluate the DED of children and its association with obesity and biomarkers of chronic disease.

Methods

In this cross-sectional study, we recruited 284 children (6-10 y) from rural Mexico. Dietary intake was assessed using three 24-h recalls. DED was calculated for "foods only" (DEDfo) and for "foods and beverages" (DEDfb). Weight, height, and body fat percent (dual-energy X-ray absorptiometry) were measured. Inflammatory cytokines, lipid profile, leptin, and insulin resistance were determined from a fasting blood sample.

Results

DEDfo was 1.91 ± 0.36 kcal/g and DEDfb was 1.36 ± 0.31 kcal/g. Higher DEDfo and DEDfb were associated with higher risk to have insulin resistance [odds ratio (OR) = 3.92, 95% confidence interval (CI): 1.66, 9.22, P < 0.01; OR = 3.51, 95% CI: 1.25, 9.87, P = 0.02, respectively]. Higher DEDfo was associated with higher risk of higher leptin levels (OR = 3.17, 95% CI: 1.01, 10.23). Also, DEDfo and DEDfb were associated with higher concentrations of cholesterol (β = 11.67, 95% CI: 1.81, 19.53, P = 0.03; and β = 11.74, 95% CI: 2.69, 20.74 P = 0.01, respectively) and higher odds of having high insulin concentrations (OR = 2.52, 95% CI: 1.26, 5.06, P = 0.01; and OR = 2.95, 95% CI: 1.30, 6.70, P = 0.01). DEDfo and DEDfb were not associated with any measure of obesity and inflammatory cytokines in the adjusted models.

Conclusions

DED was associated with higher leptin and cholesterol concentrations, and having insulin resistance, but not with any measure of obesity or inflammation. Reducing DED may reduce risk of cardiovascular disease and improve insulin sensitivity in school-aged children.

Ultraprocessed Foods and Obesity Risk: A Critical Review of Reported Mechanisms

Epidemiologic evidence supports a positive association between ultraprocessed food (UPF) consumption and body mass index. This has led to recommendations to avoid UPFs despite very limited evidence establishing causality. Many mechanisms have been proposed, and this review critically aimed to evaluate selected possibilities for specificity, clarity, and consistency related to food choice (i.e., low cost, shelf-life, food packaging, hyperpalatability, and stimulation of hunger/suppression of fullness); food composition (i.e., macronutrients, food texture, added sugar, fat and salt, energy density, low-calorie sweeteners, and additives); and digestive processes (i.e., oral processing/eating rate, gastric emptying time, gastrointestinal transit time, and microbiome). For some purported mechanisms (e.g., fiber content, texture, gastric emptying, and intestinal transit time), data directly contrasting the effects of UPF and non-UPF intake on the indices of appetite, food intake, and adiposity are available and do not support a unique contribution of UPFs. In other instances, data are not available (e.g., microbiome and food additives) or are insufficient (e.g., packaging, food cost, shelf-life, macronutrient intake, and appetite stimulation) to judge the benefits versus the risks of UPF avoidance. There are yet other evoked mechanisms in which the preponderance of evidence indicates ingredients in UPFs actually moderate body weight (e.g., low-calorie sweetener use for weight management; beverage consumption as it dilutes energy density; and higher fat content because it reduces glycemic responses). Because avoidance of UPFs holds potential adverse effects (e.g., reduced diet quality, increased risk of food poisoning, and food wastage), it is imprudent to make recommendations regarding their role in diets before causality and plausible mechanisms have been verified.

Childhood obesity in Mexico: Influencing factors and prevention strategies

Background

Overweight and obesity in school-age children, in Mexico as in other countries around the world, is a rapidly increasing public health problem within recent years, with important consequences for the future health of the population. Various national strategies at the individual and community level have been established to prevent these conditions, but none have yet succeeded.

Objective

To describe factors which influence overweight and obesity in school-age children five to 11 years old in Mexico, and national strategies for the prevention and management of these conditions.

Methods

The data herein is derived from six National Health and Nutrition Surveys in Mexico: 2006, 2012, 2016, 2018, 2020, and 2021. They include a total of 45,216 school-age children with complete anthropometric data (weight/height) distributed over 84 pseudo-panels defined by age, wellbeing condition class (WCC), gender, and type of locality of residence. The indicators calculated were overweight and obesity by body mass index according to World Health Organization guidelines. Predictors are food consumption indicators in five groups.

Results

The prevalence of overweight and obesity showed a positive linear trend (p < 0.001), with average annual increases of 0.41%. Increases in fruit consumption reduced the prevalence of these conditions by 6.6% (p = 0.01) and vegetable consumption reduced this by 8.3%.

Conclusions

Overweight and obesity in school-age children is a growing problem with serious repercussions for future life. New strategies are needed which focus on involving food systems, which translates to healthy and sustainable diets.

Evaluation of the impact of gastric bypass surgery on eating behaviour using objective methodologies under residential conditions: Rationale and study protocol

Gastric bypass surgery leads to significant and sustained weight loss and a reduction in associated health risks in individuals with severe obesity. While reduced energy intake (EI) is the primary driver of weight loss following surgery, the underlying mechanisms accounting for this energy deficit are not well understood. The evidence base has been constrained by a lack of fit-for-purpose methodology in assessing food intake coupled with follow-up studies that are relatively short-term. This paper describes the underlying rationale and protocol for an observational, fully residential study using covert, objective methodology to evaluate changes in 24-hr food intake in patients (n = 31) at 1-month pre-surgery and 3-, 12- and 24-months post-surgery, compared to weight-stable controls (n = 32). The main study endpoints included change in EI, macronutrient intake, food preferences, and eating behaviours (speed, frequency, and duration of eating). Other physiological changes that may influence EI and weight regulation including changes in body composition, circulating appetite hormones, resting metabolic rate, total energy expenditure and gastrointestinal symptoms were also evaluated. Understanding which mechanisms contribute to a reduction in EI and weight loss post-surgery could potentially help to identify those individuals who are most likely to benefit from gastric bypass surgery as well as those that may need more targeted intervention to optimise their weight loss post-surgery. Furthermore, clarification of these mechanisms may also inform targeted approaches for non-surgical treatments of obesity.

The association of dietary energy density and the risk of obesity, type 2 diabetes and metabolic syndrome: A systematic review and meta-analysis of observational studies

OBJECTIVES

There is a growing body of evidence linking dietary energy density (DED) with metabolic disorders like obesity, type 2 diabetes (T2D) and metabolic syndrome (MetS). However, according to our knowledge, there has been no systematic review and mate-analysis on T2D and MetS with DED. Therefore, this study aimed to investigate the association between DED with the risk of obesity, T2D and MetS in a systematic review and meta-analysis of observational studies.

METHODS

We searched all published studies according to the defined keywords up to march 2020 in the PubMed/Medline and Scopus databases. We excluded those that did not calculate DED for total intake, no observed association between obesity, T2D, MetS as the primary or one of the outcomes with DED, no reported odds ratio (OR), relative risk (RR) or hazard ratio (HR) estimates with 95% confidence intervals (CIs), studies in children under 2 years old, patients with cancer and pregnant women.

RESULTS

From 2282, after deleting the duplicates and irrelevant studies, we entered 58 articles ( 47 systematic reviews and 11 meta-analyse). We indicated an increased risk of T2D in relation to DED (OR: 1.25, 95% CI: 1.18-1.33, P < .001). But studies reviewed were inconsistent. All studies which examined the relationship between DED and MetS showed a positive relationship with an increased significant risk (OR: 1.59, 95% CI: 1.22-2.07, P < .001). Most articles reported a direct association between DED and obesity but the relationship between DED and risk of obesity was not significant (OR: 1.04, 95% CI: 0.92-1.17, P = .543).

CONCLUSION

In this systematic review and meta-analysis of observational studies, we found that the DED increased the risk of T2D and MetS but was not significant with the risk of obesity.

Dietary inflammatory index and dietary energy density are associated with menopausal symptoms in postmenopausal women: a cross-sectional study

OBJECTIVES

No previous study has evaluated the association of the dietary inflammatory index (DII) and dietary energy density (DED) with menopausal symptoms and its subclasses in postmenopausal women. The aim of this study was to evaluate the association of DII score and DED with menopausal symptoms and its subtypes in Iranian postmenopausal women.

METHODS

This cross-sectional study was conducted on 393 postmenopausal women who attended health centers in the south of Tehran, Iran. The DII score was calculated using dietary factors obtained by a validated food frequency questionnaire. DED was defined as average daily energy intake (kcal) per gram of food. The Menopause Rating Scale questionnaire was used to evaluate the menopausal symptoms. The total Menopause Rating Scale score (TMRSS) was the sum of the somatic score (SS), psychological score (PS), and urogenital score. Linear regression analysis was used to assess the association of the DII score and DED with menopausal symptoms.

RESULTS

After adjusting for covariates, participants in the highest tertile of DII score had greater SS compared to those in the lowest tertile (βDIIt3vs1= 0.032, 95% confidence interval (CI): 0.004-0.068, P = 0.04). No significant relationship was found between DII score and PS, urogenital score or TMRSS. Furthermore, higher DED was associated with greater SS (βDIIt3vs1 = 0.071, 95% CI: 0.028-0.115, P = 0.001), PS (βDIIt3vs1 = 0.065, 95% CI: 0.012-0.121, P = 0.01) and TMRSS (βDIIt3vs1 = 0.053, 95% CI: 0.017-0.088, P = 0.004).

CONCLUSION

A proinflammatory diet was associated with higher menopause-specific somatic symptoms and higher DED was positively associated with menopausal symptoms.

Cardiometabolic Risk is Positively Associated with Underreporting and Inversely Associated with Overreporting of Energy Intake Among European Adolescents: The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Study

BACKGROUND

Dietary misreporting is the main limitation of dietary assessments and has been associated with BMI during youth. However there are no prior studies assessing misreporting and cardiometabolic risks (CMRs) in adolescence.

OBJECTIVES

To examine the associations between dietary misreporting and CMR factors in adolescents and to assess the potential bias in the association between CMR and energy intake (EI) driven by dietary misreporting.

METHODS

Two 24-hour dietary recalls were obtained from 1512 European adolescents (54.8% girls) aged 12.5-17.5 years. Physical activity was measured by accelerometry. Cut-offs suggested by Huang were applied to identify misreporters. Height, waist circumference (WC), the sum of 4 skinfold thicknesses, diastolic blood pressure (DBP), systolic blood pressure (SBP), and cardiorespiratory fitness (CRF) measurements were taken and serum triglycerides and total-/high-density lipoprotein cholesterol ratio were analyzed. A sex- and age-specific clustered CMR score (n = 364) was computed. Associations were investigated by multilevel regression analyses adjusting for age, sex, center, socioeconomic status, and physical activity.

RESULTS

Underreporting (24.8% adolescents) was significantly (P < 0.05) associated with a higher WC, waist-to-height ratio (WHeR), and sum of skinfold thickness, whereas overreporting (23.4% adolescents) was significantly associated with a lower WC, WHeR, sum of skinfold thickness, and SBP. Associations between CMR factors and EI were significantly affected by misreporting, considering various approaches. Significant, positive associations became inverse after adjusting for misreporting for WC and WHeR. The opposite was true for the sum of skinfold thickness, SBP, and CMR score. The associations between EI and DBP and CRF did not remain significant after adjusting for misreporting.

CONCLUSIONS

CMR factors differed among misreporting groups, and both abdominal and total fat mass indicators were more strongly associated with all forms of misreporting than was BMI. Moreover, misreporting seems to bias EI and CMR associations in adolescents. Therefore, energy misreporting should be taken into account when examining diet-CMR associations.

Dietary energy density is associated with body mass index-for-age in Mexican adolescents

Dietary energy density (DED) has been widely considered a risk factor for weight gain. In adolescents, however, the evidence is inconclusive, and in Mexico, the ways in which DED is associated with overweight and obesity are unknown. Our study analysed the association of DED with overweight or obesity (OW-O) in Mexican adolescents included in the National Health and Nutrition Survey 2012 (ENSANUT 2012). We analysed the data from a 7-day Food Frequency Questionnaire administered to 2,203 Mexican adolescents aged 12-19 years. DED was calculated excluding all beverages. Plausible and implausible reporters were identified based on the relationship between the reported energy intake and the estimated energy requirement. The association of DED with body mass index (BMI)-for-age and OW-O was analysed using multivariate statistical models restricted to plausible reporters. The combined prevalence of overweight and obesity was 35.4% in the complete sample and 27.8% in the sample of plausible reporters. Mean DED was 177 kcal/100 g, with higher DED in the north of the country. The proportion of plausible reporters was 38.5%. We found a positive association between high DED and the BMI-for-age z-score (β = 0.347; 95% CI [0.101, 0.594]; P = 0.006), controlling for sociodemographic and dietary variables, but no significant association with OW-O. It is necessary to consider the DED in the design and implementation of strategies to reduce energy density in the diets of young Mexicans.

Associations of dietary energy density with body composition and cardiometabolic risk in children with overweight and obesity: role of energy density calculations, under-reporting energy intake and physical activity

This study examined (1) the association of dietary energy density from solid (EDS) and solid plus liquids (EDSL) with adiposity and cardiometabolic risk factors (CRF) in children with overweight and obesity, (2) the effect of under-reporting on the mentioned associations and (3) whether the association between ED and body composition and CRF is influenced by levels of physical activity. In a cross-sectional design, 208 overweight and obese children (8–12-year-old; 111 boys) completed two non-consecutive 24 h recalls. ED was calculated using two different approaches: EDS and EDSL. Under-reporters were determined with the Goldberg method. Body composition, anthropometry and fasting blood sample measurements were performed. Moderate to vigorous physical activity (MVPA) was registered with accelerometers (7-d-register). Linear regressions were performed to evaluate the association of ED with the previously mentioned variables. Neither EDS nor EDSL were associated with body composition or CRF. However, when under-reporters were excluded, EDS was positively associated with BMI (P=0·019), body fat percentage (P=0·005), abdominal fat (P=0·008) and fat mass index (P=0·018), while EDSL was positively associated with body fat percentage (P=0·008) and fat mass index (P=0·026). When stratifying the group according to physical activity recommendations, the aforementioned associations were only maintained for non-compliers. Cluster analysis showed that the low-ED and high-MVPA group presented the healthiest profile for all adiposity and CRF. These findings could partly explain inconsistencies in literature, as we found that different ED calculations entail distinct results. Physical activity levels and excluding under-reporters greatly influence the associations between ED and adiposity in children with overweight and obesity.

Dietary Energy Density and Its Association with Overweight or Obesity in Adolescents: A Systematic Review of Observational Studies

Dietary energy density (DED) has been identified as a crucial dietary factor in body weight control, in that higher DED has been associated with weight gain. To our knowledge, no review studies have explained this association specifically in adolescents. The aim of this study was to describe the association of DED with overweight or obesity (OW/O) in adolescents, as derived from observational studies. We conducted a systematic search of the MEDLINE/PubMed and Science Direct databases, including studies published between January 2000 and December 2017. We selected the studies that included adolescents (aged 10⁻19 years) and contained DED-related information and anthropometric measurements of OW/O. From 1149 candidate studies, 30 were selected, though only 12 met all the inclusion criteria. Of these, only four found a positive association between DED and certain OW/O indicators, six found no association and two showed an inverse association with weight gain. These studies differed in several aspects such as design, DED calculation method and dietary assessment tool, leading to inconsistent results. Methodological differences found among the examined studies did not allow us to establish a clear conclusion of this association. Evidence in adolescents was also poor. New, standardized methodological approaches should be considered in future studies.

The fight against overweight and obesity in school children: Public policy in Mexico

Excess weight in schoolchildren is a serious health problem in Mexico. In 2010, the government established General Guidelines for Dispensing or Distribution of Foods and Beverages at School Food Establishments (SFEs) in Elementary Schools with the objective of stopping the epidemic of overweight and obesity. This study aimed to evaluate compliance with the Guidelines during two academic years. With a sample of 39 schools already randomly selected, we carried out a follow-up study. The research team recorded foods and beverages available at schools in two academic years, and compared their nutritional characteristics to those established in the Guidelines. At the schools in both stages of the study, we found broad availability of energy-dense foods not allowed in the SFEs. Vegetables, fruits, and plain water accounted for less than 7 per cent of the foods and drinks. We observed no changes between stages in the compliance the Guidelines.

Predictors of Dietary Energy Density among Preschool Aged Children

Childhood obesity is a global problem with many contributing factors including dietary energy density (DED). This paper aims to investigate potential predictors of DED among preschool aged children in Victoria, Australia. Secondary analysis of longitudinal data for 209 mother–child pairs from the Melbourne Infant Feeding, Activity and Nutrition Trial was conducted. Data for predictors (maternal child feeding and nutrition knowledge, maternal dietary intake, home food availability, socioeconomic status) were obtained through questionnaires completed by first-time mothers when children were aged 4 or 18 months. Three 24-h dietary recalls were completed when children were aged ~3.5 years. DED was calculated utilizing three methods: “food only”, “food and dairy beverages”, and “food and all beverages”. Linear regression analyses were conducted to identify associations between predictors and these three measures of children’s DED. Home availability of fruits (β: −0.82; 95% CI: −1.35, −0.29, p = 0.002 for DED_food; β: −0.42; 95% CI: −0.82, −0.02, p = 0.041 for DED_{food+dairy beverages}) and non-core snacks (β: 0.11; 95% CI: 0.02, 0.20, p = 0.016 for DED_food; β: 0.09; 95% CI: 0.02, 0.15, p = 0.010 for DED_{food+dairy beverages}) were significantly associated with two of the three DED measures. Providing fruit at home early in a child’s life may encourage the establishment of healthful eating behaviors that could promote a diet that is lower in energy density later in life. Home availability of non-core snacks is likely to increase the energy density of preschool children’s diets, supporting the proposition that non-core snack availability at home should be limited.

Associations between energy density of meals and snacks and overall diet quality and adiposity measures in British children and adolescents: the National Diet and Nutrition Survey

This cross-sectional study examined how energy density (ED) of meals and snacks are associated with overall diet quality and adiposity measures in 1617 British children aged 4-18 years from the 1997 National Diet and Nutrition Survey. On the basis of data from 7-d weighed dietary record, all eating occasions were divided into meals or snacks on the basis of time (meals: 06.00-09.00, 12.00-14.00 and 17.00-20.00 hours; snacks: all others) or contribution to energy intake (EI) (meals: ≥15 %; snacks: <15 %). ED of meals and snacks was calculated on the basis of food only. Overall diet quality was assessed using the Mediterranean diet score (range 0-8). Irrespective of the definition of meals and snacks, ≥67 % of EI was derived from meals, whereas ED of meals was lower than ED of snacks (mean: 8·50-8·75 v. 9·69-10·52 kJ/g). Both ED of meals and ED of snacks were inversely associated with total intakes of vegetables, fruits, dietary fibre and overall diet quality and positively associated with total intakes of fat. However, the associations were stronger for ED of meals. The change in the Mediterranean diet score with a 1-unit increase of ED (kJ/g) was -0·35 to -0·30 for ED of meals and -0·09 to -0·06 for ED of snacks (all P<0·0001). After adjustment for potential confounders, all measures of ED of meals and snacks did not show positive associations with adiposity measures. In conclusion, although both ED of meals and ED of snacks were associated with adverse profiles of overall diet quality (but not adiposity measures), stronger associations were observed for ED of meals.

Influences on Dietary Choices during Day versus Night Shift in Shift Workers: A Mixed Methods Study

Shift work is associated with diet-related chronic conditions such as obesity and cardiovascular disease. This study aimed to explore factors influencing food choice and dietary intake in shift workers. A fixed mixed method study design was undertaken on a convenience sample of firefighters who continually work a rotating roster. Six focus groups (n = 41) were conducted to establish factors affecting dietary intake whilst at work. Dietary intake was assessed using repeated 24 h dietary recalls (n = 19). Interviews were audio recorded, transcribed verbatim, and interpreted using thematic analysis. Dietary data were entered into FoodWorks and analysed using Wilcoxon signed-rank test; p < 0.05 was considered significant. Thematic analysis highlighted four key themes influencing dietary intake: shift schedule; attitudes and decisions of co-workers; time and accessibility; and knowledge of the relationship between food and health. Participants reported consuming more discretionary foods and limited availability of healthy food choices on night shift. Energy intakes (kJ/day) did not differ between days that included a day or night shift but greater energy density (ED_energy, kJ/g/day) of the diet was observed on night shift compared with day shift. This study has identified a number of dietary-specific shift-related factors that may contribute to an increase in unhealthy behaviours in a shift-working population. Given the increased risk of developing chronic diseases, organisational change to support workers in this environment is warranted.

Associations between dietary energy density and obesity: A systematic review and meta-analysis of observational studies

OBJECTIVE

Although many studies have shown an association between dietary energy density (DED) and obesity, there has been no systematic review and meta-analysis on this topic. Therefore, the objective of this study was to qualitatively and quantitatively review and summarize the literature on association between DED and obesity.

METHODS

We searched titles, abstracts, and keywords of articles indexed in ScienceDirect, ProQuest, MEDLINE, and Google Scholar databases until January 2015 to identify eligible studies. We excluded studies that did not examine DED for whole diet and studies that included patients with cancer, pregnant women, the elderly (>60 y old), and children (<2 y old). There were no language or publication date restrictions.

RESULTS

Of the 37 studies included in this review, most articles reported a direct association between DED and obesity. We performed a meta-analysis on 23 of these studies. In comparison with the lowest NTILE of DED, subjects in the highest NTILE of DED had significant weight gain (2.26 kg, 95% confidence interval [CI]: 1.00-3.53), greater adjusted mean body mass index (BMI) (0.50 kg/m(2), 95% CI: 0.02-0.98 for males and 0.85 kg/m(2), 95% CI: 0.51-1.19 for females), and risk of excess adiposity (odds ratio [OR]: 1.27, 95% CI: 1.04-1.55). We did not observe significant associations between DED and risk of elevated BMI (OR: 1.13, 95% CI: 1.00-1.27) and abdominal obesity (OR: 1.17, 95% CI: 0.19-7.38). We found no evidence of publication bias.

CONCLUSION

The present review showed that DED was directly associated with risk of excess adiposity, higher weight change, and BMI. Lower DED should be considered a prevention strategy for obesity.

Decreasing the number of small eating occasions (<15 % of total energy intake) regardless of the time of day may be important to improve diet quality but not adiposity: a cross-sectional study in British children and adolescents

Evidence of associations between meal frequency (MF) and snack frequency (SF) and diet and obesity in young populations is limited. This cross-sectional study examined MF and SF in relation to dietary intake and adiposity measures in British children aged 4-10 years (n 818) and adolescents aged 11-18 years (n 818). Based on data from a 7-d weighed dietary record, all eating occasions were divided into meals or snacks on the basis of contribution to energy intake (≥15 or <15 %) or time (06.00-10.00, 12.00-15.00 and 18.00-21.00 hours or others). All measures of MF and SF showed positive associations with energy intake, except for MF based on energy contribution in children. Irrespective of the definition of snacks, SF was associated with higher intakes of soft drinks, confectionery and total sugar, lower intakes of cereals, fish, meat, protein, PUFA, starch and dietary fibre, and a lower diet quality (assessed by the Mediterranean diet score, except for SF based on energy contribution in adolescents). MF based on time, but not based on energy contribution, was associated with higher intakes of confectionery and total sugar, lower intakes of fish, protein, PUFA and starch, and, only in children, a lower diet quality. All measures of MF and SF showed no association with adiposity measures. In conclusion, this cross-sectional study in British children and adolescents suggests that decreasing the number of small eating occasions (<15 % of total energy intake) regardless of the time of day may be important to improve diet quality but not adiposity.

Associations between meal and snack frequency and diet quality and adiposity measures in British adults: findings from the National Diet and Nutrition Survey

Objective

To examine how different definitions of meals and snacks can affect the associations of meal frequency (MF) and snack frequency (SF) with dietary intake and adiposity measures.

Design

Based on 7 d weighed dietary record data, all eating occasions providing ≥210 kJ of energy were divided into meals or snacks based on contribution to energy intake (≥15 % or <15 %) or time (06.00–10.00, 12.00–15.00 and 18.00–21.00 hours; other). Diet quality was assessed using the Healthy Diet Indicator (HDI) and Mediterranean Diet Score (MDS).

Setting

Great Britain.

Subjects

British adults aged 19–64 years (n 1487).

Results

MF based on energy contribution was associated with higher intake of dietary fibre, lower intakes of non-milk extrinsic sugars and alcohol, and higher HDI (only men) and MDS. MF based on time was associated with higher HDI and MDS in women only. Conversely, irrespective of the definition of snacks, SF was associated with higher intakes of confectionery and alcohol, lower intakes of cereals, protein, fat and dietary fibre, and lower HDI (except for SF based on energy contribution in women) and MDS. After adjustment for potential confounders, MF based on time, but not MF based on energy contribution, was positively associated with BMI and waist circumference in men only. SF was positively associated with BMI and waist circumference, irrespective of the definition of snacks.

Conclusions

Higher SF was consistently associated with lower diet quality and higher adiposity measures, while associations with MF varied depending on the definition of meals and sex.

The Cross-Sectional Association of Energy Intake and Dietary Energy Density with Body Composition of Children in Southwest China

OBJECTIVE

We examined whether dietary energy intake (EI) and dietary energy density (ED) were cross-sectionally associated with body composition of children living in Southwest China.

DESIGN AND METHODS

Multivariate regression analyses were performed on three day, 24 h dietary recall data and information on potential confounders from 1207 participants aged 8-14 years. EI was calculated from all foods and drinks and ED was classified into five categories. Body mass index (BMI) z-scores, percentage of body fat (%BF), fat mass index (FMI), fat-free mass index (FFMI) and ratio of waist to hip circumference (WHR) were used to describe body composition.

RESULTS

Boys with higher total EI had higher BMI z-scores, %BF, and FMI than boys with lower total EI both before and after measurements were adjusted for confounders (age, fiber intake, physical activity, the timing of adding complementary foods, paternal education level and maternal BMI) (p ≤ 0.04). However, EI was not associated with body composition in girls. Dietary ED, in any category, was not associated with body composition in either gender.

CONCLUSIONS

Dietary ED was not associated with body composition of children in Southwest China, while dietary EI in boys, not girls, was positively associated with body composition. Reducing dietary energy intake may help to prevent obesity and related diseases in later life among boys living in Southwest China.

Usual Dietary Energy Density Distribution Is Positively Associated with Excess Body Weight in Mexican Children

BACKGROUND

Studies suggest a positive association between dietary energy density (DED) and body weight in adults, but evidence in children is inconclusive.

OBJECTIVE

The objective of this study was to compare usual DED distributions of nonoverweight vs. overweight or obese (OW/O) Mexican children.

METHODS

The study used 24-h recall (24HR) data from 2367 children aged 5-11 y from the 2012 Mexican National Health and Nutrition Survey (ENSANUT 2012). Repeated 24HR measures were obtained in a random sample (∼10%) to estimate usual intake distributions by using the Iowa State University (PC-Side) method. Implausible dietary reports were identified. Multivariate linear regression models were used to evaluate the relation between DED and body mass index status and to compare results with and without PC-Side adjustment and restriction to plausible reporters.

RESULTS

A total of 35.1% of the children in the sample were OW/O. The usual DED mean was ∼175 kcal/100 g in both the complete sample and the plausible reporters subsample. Regression models adjusted by PC-Side and for potential confounders showed higher DED in OW/O relative to nonoverweight children for both plausible reporters (9.7 kcal/100 g; n = 1452, P < 0.0001) and the complete sample (7.9 kcal/100 g; n = 2367, P < 0.0001). The DED difference in plausible reporters translates into 88 additional kilocalories in daily energy intake of OW/O children. In the absence of PC-side adjustment, the difference was significant for plausible reporters (P < 0.05) but not for the complete sample (P > 0.10).

CONCLUSIONS

A positive association between usual DED and OW/O was found in Mexican children. The association was stronger when only plausible reporters were considered. This suggests that there is a need for strategies to reduce energy density in the diet of Mexican children.

Dietary energy density in young children across Europe

OBJECTIVES

To describe energy density (ED; kcal g(-1)) of dietary intake of European children.

METHODS

From 16, 228 children who participated in the IDEFICS (Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS) baseline examination, 8551 children with 24-h dietary recalls (24-HDR), with plausible reported energy intakes and complete covariate information were included in the present analysis. ED was calculated using two methods: (1) ED including solid foods (EDF) and (2) ED including solid foods and energy-containing beverages (EDF&B). Beverage energy was calculated in kcal per day. Dietary characteristics and body mass index (BMI) z-score of children aged 2 to <6 years and 6 to <10 years were compared between children with an overall EDF below the <25th percentile, between the 25th and 75th percentile as well as above the >75th percentile. Standardised regression coefficients were estimated to assess the association between dietary characteristics, BMI z-score and ED of the diet.

RESULTS

Children with low EDF and EDF&B diets consumed less energy but higher quantity of food and beverages than children with high EDF and EDF&B diets. Consumption of caloric beverages decreased with increasing EDF&B of the diet owing to the relatively low ED of the beverages, in relation to solid foods. Generally, children with low EDF and EDF&B diets showed healthier food choices than peers with higher EDF and EDF&B diets. In this sample, EDF and EDF&B were not associated with BMI z-score.

CONCLUSION

Health promotion strategies should proclaim lower ED diets by means of foods with high water and low fat content and mainly fruit and vegetable components. Excluding caloric beverages from EDF calculation is a useful method to avoid misinterpretation of true exposure to a high energy dense diet. We recommend excluding caloric beverages from EDF calculation when investigating the effect of ED on a certain (health) outcome.

Dietary energy density: estimates, trends and dietary determinants for a nationally representative sample of the Irish population (aged 5–90 years)

Higher dietary energy density (DED) has been reported to be associated with weight gain, obesity and poorer dietary quality, yet nationally representative estimates that would allow tracking of secular trends and inter-country comparisons are limited. The aims of the present study were to calculate DED estimates for the Irish population and to identify dietary determinants of DED. Weighed/semi-weighed food records from three cross-sectional surveys (the National Children's Food Survey, the National Teens’ Food Survey and the National Adult Nutrition Survey) were collated to estimate habitual dietary intakes for a nationally representative sample of the Irish population, aged 5–90 years (n2535). DED estimates, calculated using the total diet method, the food only method and a novel method, including foods and solids in beverages, were 3·70 (sd1·09), 7·58 (sd1·72) and 8·40 (sd1·88) kJ/g, respectively. Determinants of DED did not vary by the calculation method used. Variation in the intakes of fruit, vegetables and sugar-sweetened beverages (SSB) across consumer groups contributed to the largest variance in DED estimates, followed by variation in the intakes of potatoes, fresh meat, bread, chips, ready-to-eat breakfast cereals, and confectionery. DED estimates were inversely associated with age group and consistently lower for females than for males. The inverse association of DED with age group was explained by higher intakes of vegetables, fruit, fish, potatoes, fresh meat and brown bread and lower intakes of SSB, chocolate confectionery, ready-to-eat breakfast cereals and savoury snacks in older age groups. Females consumed, on average, 1·5 times more fruit and vegetables combined when compared with males, largely explaining the sex differences in DED estimates. Current DED estimates for adults were similar to those calculated in a previous survey, carried out 10 years earlier. These estimates and determinants serve as a baseline for comparison for other works and public health campaigns.

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.

Influencing and modifying children's energy intake: the role of portion size and energy density

Childhood obesity is of concern worldwide. The portion size (PS) and energy density (ED) of food are two major determinants of children's energy intake (EI). Trends towards increasing PS are most apparent and best documented in the USA, where PS of numerous food products have increased in the marketplace over the past three decades, particularly high-energy dense foods. Analyses of population-level dietary surveys have confirmed this trend in children for both in- and out-of-home eating, and a plethora of observational evidence positively associates PS, ED and adiposity in children. A limited number of intervention studies provide clear evidence that children, even as young as 2 years, respond acutely to increasing PS, with some studies also demonstrating the additive effects of increased ED in promoting excessive EI. However, most of the evidence is based on children aged 3-6 years and there is a paucity of data in older children and adolescents. It is unclear whether decreasing PS can have the opposite effect on children's EI but recent acute studies have demonstrated that the incorporation of lower energy dense foods, such as fruit and vegetables, into children's meals down-regulates EI. Although a direct causal link between PS and obesity remains to be established, the regular consumption of larger PS of energy dense foods do favour obesity-promoting eating behaviours in children. Further research is required to establish the most feasible and effective interventions and policies to counteract the deleterious impact of PS and ED on children's EI.

Energy density of the Scottish diet estimated from food purchase data: relationship with socio-economic position and dietary targets

Frequent consumption of energy-dense foods has been strongly implicated in the global increase of obesity. The World Cancer Research Fund suggests a population-level energy density (ED) goal for diets of 523 kJ/100 g (125 kcal/100 g) as desirable for reducing weight gain and related co-morbidities. However, there is limited information about the ED of diets of contemporary populations. The aims of the present study were to (1) estimate the mean ED of the Scottish diet, (2) assess differences in ED over time by socio-economic position, by household (HH) composition and for HH meeting dietary targets for fat and fruit and vegetables, and (3) assess the relationship between ED and the consumption of foods and nutrients, which are indicative of diet quality. ED of the diet was estimated from food (including milk) from UK food purchase survey data. The average ED of the Scottish diet was estimated as 718 kJ/100 g with no change between the survey periods 2001 and 2009. Individuals living in the most deprived areas had a higher mean ED than those living in the least deprived areas (737 v. 696 kJ/100 g). Single-parent HH had the highest mean ED (765 kJ/100 g) of all the HH surveyed. The mean ED of HH achieving dietary targets for fat and fruit and vegetables was 576 kJ/100 g compared with 731 kJ/100 g for non-achievers. HH within the lowest quintile of ED were, on average, closest to meeting most dietary guidelines. Food purchase data can be used to monitor the quality of the diet in terms of dietary ED of the population and subgroups defined by an area-based measure of socio-economic status.

Individualized tailor-made dietetic intervention program at schools enhances eating behaviors and dietary habits in obese Hispanic children of low socioeconomic status

Hispanic children and those from low-socioeconomic status are predisposed to unhealthy eating habits and obesity.

AIM

to implement an individualized, face-to-face, parent supported, and school-partnership dietetic intervention to promote healthy eating habits and decrease body mass index. Prospective school year dietetic intervention of 101 obese, Hispanic, low-socioeconomic school-age children representative of Monterrey, Mexico, consisted of anthropometrics, dietetic assessment, energy-restriction tailor-made daily menus, and parental education every three weeks. Student's t-test was used for means comparison. A significant decrease was found in body mass index percentile (96.43 ± 3.32 to 93.42 ± 8.12/P = 0.00) and energy intake/day of -755.7 kcal/day (P = 0.00). Among other energy dense foods with significant decline in servings/day and servings/week were processed meats (3.13 ± 1.43 to 2.19 ± 1.04/P = 0.00 and 5.60 ± 1.75 to 4.37 ± 2.10/P = 0.00, resp.), saturated fat (1.47 ± 1.08 to 0.78 ± 0.79/P = 0.00 and 2.19 ± 2.18 to 1.1 ± 1.36/P = 0.00), sweetened beverages (2.79 ± 1.99 to 1.42 ± 1.21 and 6.21 ± 1.72 to 3.89 ± 2.80/P = 0.00), and desserts and refined-grain bakery (1.99 ± 1.54 to 1.32 ± 1.59 and 2.85 ± 2.54 to 1.57 ± 2.20/P = 0.00). There was a significant increase in servings/day and servings/week of water (2.98 ± 2.02 to 4.91 ± 2.37 and 6.62 ± 2.03 to 6.87 ± 0.91/P = 0.00, resp.) and nutrient dense foods such as fruits (1.31 ± 0.89 to 1.66 ± 0.96 and 3.34 ± 2.24 to 4.28 ± 2.43/P = 0.00) and fish and poultry (3.76 ± 2.15 to 4.54 ± 2.25/P = 0.00). This intervention created healthy eating habits and decreased body mass index in a high risk population.

TRIAL REGISTRATION NUMBER

NCT01925976.

Factors associated with development of excessive fatness in children and adolescents: a review of prospective studies

The purpose of this review was to examine the factors that predict the development of excessive fatness in children and adolescents. Medline, Web of Science and PubMed were searched to identify prospective cohort studies that evaluated the association between several variables (e.g. physical activity, sedentary behaviour, dietary intake and genetic, physiological, social cognitive, family and peer, school and community factors) and the development of excessive fatness in children and adolescents (5-18 years). Sixty-one studies met the eligibility criteria and were included. There is evidence to support the association between genetic factors and low physical activity with excessive fatness in children and adolescents. Current studies yielded mixed evidence for the contribution of sedentary behaviour, dietary intake, physiological biomarkers, family factors and the community physical activity environment. No conclusions could be drawn about social cognitive factors, peer factors, school nutrition and physical activity environments, and the community nutrition environment. There is a dearth of longitudinal evidence that examines specific factors contributing to the development of excessive fatness in childhood and adolescence. Given that childhood obesity is a worldwide public health concern, the field can benefit from large-scale, long-term prospective studies that use state-of-the-art measures in a diverse sample of children and adolescents.

Determinants of Attrition to Follow-Up in a Multicentre Cohort Study in Children-Results from the IDEFICS Study

Cohort participant retention is a crucial element and may depend on several factors. Based on data from a multicentre cohort of European children, the effect of baseline participation on attrition and the association with and the impact of single determinants in relation to the extent of attrition were investigated. Data was available for 16,225 children from the IDEFICS baseline survey (2007/2008). Attrition was defined as nonparticipation in the first follow-up examination (2009/2010). Determinants of attrition were analysed by logistic regression. The statistical significance level was set at α=0.01 to account for the large sample size. The strongest associations were seen for baseline item non-response, especially when information on migration background (odds ratio (OR) = 1.55; 99% confidence interval (CI): 1.04, 2.31), single parenthood (OR = 1.37; 99% CI: 1.12, 1.67), or well-being (OR = 1.46; 99% CI: 1.19, 1.79) was lacking. Drop-out proportion rose with the number of missing items. Overweight, low education, single parenthood and low well-being scores were independent determinants of attrition. Baseline participation, and the individual determinant effects seemed unrelated to the variation of the extent of attrition between study centres. A high level of item nonresponse as well as overweight and disadvantageous sociodemographic conditions were identified as main attrition determinants, suggesting the consideration of these aspects in conduct and analysis of cohort studies in childhood obesity research.

Using the Theory of Planned Behavior to Predict Two Types of Snack Food Consumption among Midwestern Upper Elementary Children: Implications for Practice

This study examined the extent to which constructs of the theory of planned behavior (TPB) can predict the consumption of two types of snack foods among elementary school children. A 15-item instrument tested for validity and reliability measuring TPB constructs was developed and administered to 167 children. Snack foods were evaluated using a modified 24-hour recall method. On average, children consumed 302 calories from snack foods per day. Stepwise multiple regression found that attitudes, subjective norms, and perceived control accounted for 44.7% of the variance for intentions. Concurrently, intentions accounted for 11.3% of the variance for caloricallydense snack food consumption and 8.9% of the variance for fruit and vegetable snack consumption. Results suggest that the theory of planned behavior is an efficacious theory for these two behaviors. Future interventions should consider using this theoretical framework and aim to enhance children's attitudes, perceived control, and subjective norms towards snack food consumption.

Dietary energy density and body weight in adults and children: a systematic review

Energy density is a relatively new concept that has been identified as an important factor in body weight control in adults and in children and adolescents. The Dietary Guidelines for Americans 2010 encourages consumption of an eating pattern low in energy density to manage body weight. This article describes the systematic evidence-based review conducted by the 2010 Dietary Guidelines Advisory Committee (DGAC), with support from the US Department of Agriculture's Nutrition Evidence Library, which resulted in this recommendation. An update to the committee's review was prepared for this article. PubMed was searched for English-language publications from January 1980 to May 2011. The literature review included 17 studies (seven randomized controlled trials, one nonrandomized controlled trial, and nine cohort studies) in adults and six cohort studies in children and adolescents. Based on this evidence, the 2010 Dietary Guidelines Advisory Committee concluded that strong and consistent evidence in adults indicates that dietary patterns relatively low in energy density improve weight loss and weight maintenance. In addition, the committee concluded that there was moderately strong evidence from methodologically rigorous longitudinal cohort studies in children and adolescents to suggest that there is a positive association between dietary energy density and increased adiposity. This review supports a relationship between energy density and body weight in adults and in children and adolescents such that consuming diets lower in energy density may be an effective strategy for managing body weight.

Association of dietary energy density in childhood with age and body fatness at the onset of the pubertal growth spurt

The aim of the present study was to examine the association of pre-pubertal dietary energy density (ED) with both age and body fatness at the start of the pubertal growth spurt (age at take-off, ATO). Analyses included 219 DOrtmund Nutritional and Anthropometric Longitudinally Designed Study participants with sufficient height measurements to estimate ATO who provided 3 d weighed dietary records at baseline, i.e. 2 and 3 years before ATO (mean age 6·9 (sd 1·2) years). Mean energy intakes and amounts of foods/drinks consumed at baseline were derived from the records. ED (kJ/g) was calculated based on (1) all foods and drinks (ED_all), (2) foods and energy-containing drinks (ED_energy), (3) foods and milk as a drink, but no other beverages (ED_milk) and (4) foods only, solid or liquid (ED_food). Using multiple regression analyses, the association between the ED variables and ATO was investigated. Furthermore, Z-scores of BMI and fat mass index (FMI) at ATO were considered as outcomes to reflect body fatness at puberty onset. The results showed that ED at baseline was not associated with ATO, regardless of the ED method used. For example, mean ATO in the lowest v. highest tertile of ED_food was 9·3 (95 % CI 9·0, 9·5) v. 9·4 (95 % CI 9·1, 9·7) years, Ptrend = 0·8 (adjusted for sex, maternal age, birth weight, dietary protein, dietary fibre, baseline BMI Z-score). Similarly, ED was not independently associated with BMI or FMI Z-score at ATO (Ptrend = 0·3–0·9). In conclusion, dietary ED in childhood did not influence timing or body fatness at ATO in this cohort of healthy, free-living children.

Diet quality is independently associated with weight status in children aged 9-10 years

Although energy imbalance is key to the development of childhood obesity, the association between different dietary components, reflected in diet quality scores, and children's weight status has not been extensively studied. The current study determined if diet quality, characterized according to 3 predefined scores, was associated with weight status in a population-based sample of 9- to 10-y-old British children, independently of factors previously associated with weight status. In a cross-sectional study of 1700 children (56% girls), data from 4-d food diaries were used to calculate 3 diet quality scores modified to be reflective of children's diets: the Diet Quality Index (DQI), Healthy Diet Indicator (HDI), and Mediterranean Diet Score (MDS). Physical activity was measured with 7-d accelerometery, and height, weight, waist, and bio-impedance were objectively measured and used to calculate weight status variables. After multiple adjustments, including physical activity and overall energy density, higher DQI and HDI scores were significantly associated with improved weight status. Comparing extreme quintiles of the scores revealed the DQI and HDI were associated with lower waist circumference (-3.0%, P = 0.005 and -2.5%, P = 0.033, respectively), and lower body fat (-5.1%, P = 0.023 and -4.9%, P = 0.026, respectively). The DQI was also associated with lower weight (-5.9%; P = 0.002) and BMI (-4.2%; P = 0.004). No significant associations were observed with the MDS. These findings suggest that diet quality is independently associated with children's weight status. Future work should consider if diet quality scores could be key components of interventions designed to reduce obesity in children.

Dietary energy density and adiposity: employing bias adjustments in a meta-analysis of prospective studies

BACKGROUND

Dietary studies differ in design and quality making it difficult to compare results. This study quantifies the prospective association between dietary energy density (DED) and adiposity in children using a meta-analysis method that adjusts for differences in design and quality through eliciting and incorporating expert opinion on the biases and their uncertainty.

METHOD

Six prospective studies identified by a previous systematic literature search were included. Differences in study quality and design were considered respectively as internal and external biases and captured in bias checklists. Study results were converted to correlation coefficients; biases were considered either additive or proportional on this scale. The extent and uncertainty of the internal and external biases in each study were elicited in a formal process by five quantitatively-trained assessors and five subject-matter specialists. Biases for each study were combined across assessors using median pooling and results combined across studies by random-effects meta-analysis.

RESULTS

The unadjusted combined correlation between DED and adiposity change was 0.06 (95%CI 0.01, 0.11; p = 0.013), but with considerable heterogeneity (I² = 52%). After bias-adjustment the pooled correlation was 0.17 (95%CI - 0.11, 0.45; p = 0.24), and the studies were apparently compatible (I² = 0%).

CONCLUSIONS

This method allowed quantitative synthesis of the prospective association between DED and adiposity change in children, which is important for the development of evidence-informed policy. Bias adjustment increased the magnitude of the positive association but the widening confidence interval reflects the uncertainty of the assessed biases and implies that higher quality studies are required.

[Diet and eating habits in relation to the development of obesity in children and adolescents]

Diet is of major interest in research on the etiology of obesity. Research in this field comprises investigation of the role of individual nutrients and foods, nutrient composition, as well as dietary patterns and habits. Longitudinal data on the association between dietary factors and the development of obesity in childhood and adolescence are sparse; therefore, conclusions on the impact of energy density, consumption of carbohydrates and proteins, snack foods and fast food, meal patterns and speed of eating cannot be drawn. More data exist with respect to the role of energy intake and consumption of fat and sugar-sweetened beverages; however, findings are inconsistent. This could be due to methodological shortcomings that mark dietary assessment in children and adolescents. However, as a direct modulator of energy balance, diet still needs to be part of a comprehensive strategy to combat overweight and obesity in children and adolescents.

Relationship of physical activity and dietary habits with body mass index in the transition from childhood to adolescence: a 4-year longitudinal study

Objective

To explore the relationship between several physical activity (PA) and dietary behaviours and BMI Z-score and to investigate the relationship between changes in these variables and in the BMI Z-score over a 4-year period from childhood to adolescence.

Design

Longitudinal study in which children were included in the fifth grade and measured for four consecutive years. Dietary and PA behaviours as well as height and weight were measured by means of self-reported validated questionnaires.

Setting

Fifty-nine Flemish elementary schools.

Subjects

The baseline sample consisted of 51·9 % boys and the mean age was 10 (sd 0·4) years. During the first measurement year (2002), data on 1670 fifth graders were gathered. These measurements were repeated after 1 (n 1557), 2 (n 1151) and 3 (n 807) years.

Results

Significant inverse relationships with BMI Z-score were observed for frequency of breakfast consumption (β = −0·033, se = 0·012) and frequency of sports participation (β = −0·011, se = 0·004) across four time points. Significant inverse relationships between changes in BMI Z-score and changes in frequency of sports participation (β = −0·011, se = 0·006) and hours of physical education (PE; β = −0·052, se = 0·023) were observed, meaning that decreases in sports participation and hours spent in PE were associated with increases in BMI Z-score.

Conclusions

The present study provides an important insight into different dietary and PA behaviours related to (changes in) BMI Z-score during the transition from childhood to adolescence.

Eating behaviors of children in the context of their family environment

Both a family history of obesity and early childhood obesity have been identified as strong predictors of adult obesity risk. The finding that parental obesity, maternal obesity in particular, increases a child's risk for developing obesity suggests that either shared genes, or environment, or likely a combination of both may promote overeating and excessive weight gain in children. Parents not only create food environments for children's early experiences with food and eating, but they also influence their children's eating by modeling their own eating behaviors, taste preferences, and food choices. Thus, it is important to identify intermediary behavioral eating traits which promote overeating and obesity in children and to determine the extent to which associations between eating traits and excessive weight gain in children may be influenced by genetic factors, environmental factors, or both. Behavioral genetic methods can be used to help partition genetic and environmental sources of variability in behavioral traits. The focus of this paper is to review and discuss findings from both short-term experimental and prospective cohort studies on eating behaviors of children at various stages in their lives. Select child eating traits and parent-child resemblances in eating will be further examined in the context of children's home environment and their familial predisposition to obesity. The paper represents an invited review by a symposium, award winner or keynote speaker at the Society for the Study of Ingestive Behavior [SSIB] Annual Meeting in Portland, July 2009.

Parental influence on children's early eating environments and obesity risk: implications for prevention

Most childhood obesity prevention efforts have focused on school-age children and adolescents and have had limited success. We argue that the first years of life, including the prenatal period, the postnatal suckling period and the transition to the modified adult diet, may provide opportunities for preventive interventions. These early periods are characterized by high plasticity and rapid transitions, and parents have a high degree of control over children's environments and experiences. Observational and experimental evidence reveal persistent effects of early environments on eating behavior and obesity risk, suggesting that interventions should be tested during these early periods. The central task parents have in early development points to their potential as key targets and agents of change in early preventive interventions. In this paper, we review evidence of early environmental effects on children's eating and obesity risk, highlighting ways that parental feeding practices and parents' own behaviors impact these outcomes and calling for further experimental research to elucidate whether these factors are indeed promising targets for childhood obesity preventive interventions.

Change in dietary energy density after implementation of the Texas Public School Nutrition Policy

Consumption of energy-dense foods has been associated with rising obesity rates and the metabolic syndrome. Reducing dietary energy density is an important strategy to address obesity, but few studies have examined the effect of nutrition policies on children's energy density. The study's objective was to assess the impact of the Texas Public School Nutrition Policy on children's energy density by using a pre- and post-policy evaluation. Analysis of variance/covariance and nonparametric tests compared energy density after the Texas policy change to intakes at baseline. Two years of lunch food records were collected from middle school students in Southeast Texas at three public middle schools: baseline (2001-2002) and 1 year after implementation of the Texas Policy (2005-2006). Students recorded the amount and source of foods consumed. The Texas Public School Nutrition Policy was designed to promote a healthy school environment by restricting portion sizes of high-fat and high-sugar snacks and sweetened beverages, fat content of foods, and serving of high-fat vegetables like french fries. Energy density (kcal/g): energy density-1 was the energy of foods only (no beverages) divided by the gram weight and has been previously associated with obesity and insulin resistance; energy density-2 included all food and beverages to give a complete assessment of all sources of calories. Following implementation of the Texas policy, students' energy density-1 significantly decreased from 2.80+/-1.08 kcal/g to 2.17+/-0.78 kcal/g (P<0.0001). Similarly, energy density-2 significantly decreased from 1.38+/-0.76 kcal/g to 1.29+/-0.53 kcal/g (P<0.0001). In conclusion, the Texas Public School Nutrition Policy was associated with desirable reductions in energy density, which suggests improved nutrient intake as a result of student school lunch consumption.

Dietary energy density as a marker of dietary quality in Swedish children and adolescents: the European Youth Heart Study

OBJECTIVE

To investigate if dietary energy density is associated with measures of dietary quality (food group, micronutrient and macronutrient intakes) in children and adolescents.

SUBJECTS/METHODS

In all, 551 children (mean age 9.6 years, 52% girls) and 569 adolescents (15.5 years, 55% girls), sampled from schools in Sweden, completed a single 24-h dietary recall. Dietary energy density (kJ/g) was calculated as the energy from all food consumed divided by the weight of all food consumed. Beverages were excluded from the calculation. Food and micronutrient intakes were adjusted for energy intake. A one-way analysis of variance (ANOVA) was used to test for differences in food group and nutrient intakes across age- and gender-specific tertiles of energy density. Discriminant analysis was used to confirm the groupings formed by tertiles.

RESULTS

Subjects with low-energy-density diets were significantly more likely to consume fruits, vegetables, pasta, rice, potatoes and cereals and less likely to consume sweetened drinks, sweets and chocolate. After energy adjustment, their intakes of many foods recommended in the Swedish food-based dietary guidelines were higher and intakes of nutrient-poor foods were lower. The macronutrient energy profile (% energy) of low-energy-density diets was closest to the recommended level. Low-energy-density diets contained greater amounts of most micronutrients. Discriminant analysis confirmed the existence of heterogeneous dietary patterns and the likelihood of correct classification by energy density in 65% of cases.

CONCLUSIONS

Lower dietary energy density is associated with better dietary quality in children and adolescents. Energy density has advantages over other whole diet analysis methods and may be suitable as a simple proxy of diet quality.

Plenary Lecture 1: Dietary strategies for the prevention and treatment of obesity

Obesity is a rapidly-growing public health problem that is related in part to the foods available in the eating environment. Properties of foods such as portion size and energy density (kJ/g) have robust effects on energy intake; large portions of energy-dense foods promote excess consumption and this effect starts in early childhood. Studies show, however, that in both adults and children these food characteristics can also be used strategically to moderate energy intake, as well as to improve diet quality. Dietary energy density can be reduced by increasing intake of water-rich foods such as vegetables and fruits. Their high water content allows individuals to eat satisfying portions of food while decreasing energy intake. Filling up at the start of a meal with vegetables or fruit and increasing the proportion of vegetables in a main course have been found to control hunger and moderate energy intake. Data from several clinical trials have also demonstrated that reducing dietary energy density by the addition of water-rich foods is associated with substantial weight loss even though participants eat greater amounts of food. Population-based assessments indicate that beginning in childhood there is a relationship between consuming large portions of energy-dense foods and obesity. These data suggest that the promotion of diets that are reduced in energy density should be an important component of future efforts to both prevent and treat obesity.

Reflections from a systematic review of dietary energy density and weight gain: is the inclusion of drinks valid?

The association between dietary energy density, increased energy intake and weight gain is supported by experimental evidence, but confirmation of an effect in free-living humans is limited. Experimental evidence supports a role of energy density in obesity through changes in food composition, not drinks consumption. The inclusion of drinks in the calculation creates a variable of questionable validity and has a substantive impact on the estimated energy density of the diet. We posit, based on the experimental evidence, that calculating the energy density of diets by excluding drinks and including calories from drinks as a covariate in the analysis is the most valid and reliable method of testing the relationship between energy density and weight gain in free-living humans. We demonstrate, by systematically reviewing existing observational studies of dietary energy density and weight gain in free-living humans, how current variation in the method for calculating energy density hampers the interpretation of these data. Reaching an a priori decision on the appropriate methodology will reduce the error caused by multiple comparisons and facilitate meaningful interpretation of epidemiological evidence to inform the development of effective obesity prevention strategies.

Dietary energy density in relation to subsequent changes of weight and waist circumference in European men and women

Background

Experimental studies show that a reduction in dietary energy density (ED) is associated with reduced energy intake and body weight. However, few observational studies have investigated the role of ED on long-term weight and waist circumference change.

Methods and Principal Findings

This population-based prospective cohort study included 89,432 participants from five European countries with mean age 53 years (range: 20–78 years) at baseline and were followed for an average of 6.5 years (range: 1.9–12.5 years). Participants were free of cancer, cardiovascular diseases and diabetes at baseline. ED was calculated as the energy intake (kcal) from foods divided by the weight (g) of foods. Multiple linear regression analyses were performed to investigate the associations of ED with annual weight and waist circumference change.

Mean ED was 1.7 kcal/g and differed across study centers. After adjusting for baseline anthropometrics, demographic and lifestyle factors, follow-up duration and energy from beverages, ED was not associated with weight change, but significantly associated with waist circumference change overall. For 1 kcal/g ED, the annual weight change was −42 g/year [95% confidence interval (CI): −112, 28] and annual waist circumference change was 0.09 cm/year [95% CI: 0.01, 0.18]. In participants with baseline BMI<25 kg/m², 1 kcal/g ED was associated with a waist circumference change of 0.17 cm/year [95% CI: 0.09, 0.25].

Conclusion

Our results suggest that lower ED diets do not prevent weight gain but have a weak yet potentially beneficial effect on the prevention of abdominal obesity as measured by waist circumference.

The relationship between dietary energy density and energy intake

Much of the research in ingestive behavior has focused on the macronutrient composition of foods; however, these studies are incomplete, or could be misleading, if they do not consider the energy density (ED) of the diet under investigation. Lowering the ED (kcal/g) by increasing the volume of preloads without changing macronutrient content can enhance satiety and reduce subsequent energy intake at a meal. Ad libitum intake or satiation has also been shown to be influenced by ED when the proportions of macronutrients are constant. Since people tend to eat a consistent weight of food, when the ED of the available foods is reduced, energy intake is reduced. The effects of ED have been seen in adults of different weight status, sex, and behavioral characteristics, as well as in 3- to 5-year-old children. The mechanisms underlying the response to variations in ED are not yet well understood and data from controlled studies lasting more than several days are limited. However, both population-based studies and long-term clinical trials indicate that the effects of dietary ED can be persistent. Several clinical trials have shown that reducing the ED of the diet by the addition of water-rich foods such as fruits and vegetables was associated with substantial weight loss even when patients were not told to restrict calories. Since lowering dietary energy density could provide effective strategies for the prevention and treatment of obesity, there is a need for more studies of mechanisms underlying the effect and ways to apply these findings.

Dietary energy density affects fat mass in early adolescence and is not modified by FTO variants

Background

Dietary energy density (DED) does not have a simple linear relationship to fat mass in children, which suggests that some children are more susceptible than others to the effects of DED. Children with the FTO (rs9939609) variant that increases the risk of obesity may have a higher susceptibility to the effects of DED because their internal appetite control system is compromised. We tested the relationship between DED and fat mass in early adolescence and its interaction with FTO variants.

Methods and Findings

We carried out a prospective analysis on 2,275 children enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC). Diet was assessed at age 10 y using 3-day diet diaries. DED (kJ/g) was calculated excluding drinks. Children were genotyped for the FTO (rs9939609) variant. Fat mass was estimated at age 13 y using the Lunar Prodigy Dual-energy X-ray Absorptiometry scanner. There was no evidence of interaction between DED at age 10 y and the high risk A allele of the FTO gene in relation to fat mass at age 13 y (β = 0.005, p = 0.51), suggesting that the FTO gene has no effect on the relation between DED at 10 y and fat mass at 13 y. When DED at 10 y and the A allele of FTO were in the same model they were independently related to fat mass at 13 y. Each A allele of FTO was associated with 0.35±0.13 kg more fat mass at 13 y and each 1 kJ/g DED at 10 y was associated with 0.16±0.06 kg more fat mass at age 13 y, after controlling for misreporting of energy intake, gender, puberty, overweight status at 10 y, maternal education, TV watching, and physical activity.

Conclusions

This study reveals the multi-factorial origin of obesity and indicates that although FTO may put some children at greater risk of obesity, encouraging a low dietary energy density may be an effective strategy to help all children avoid excessive fat gain.

Dietary energy density predicts the risk of incident type 2 diabetes: the European Prospective Investigation of Cancer (EPIC)-Norfolk Study

OBJECTIVE

Accumulating evidence suggests that energy-dense foods predispose to obesity and that such foods may also be associated with an increased risk of type 2 diabetes, but there is limited evidence. Our aim was to investigate whether there is an independent association between dietary energy density and incidence of diabetes.

RESEARCH DESIGN AND METHODS

The European Prospective Investigation of Cancer (EPIC)-Norfolk Cohort Study was a population-based prospective study of individuals aged 40-79 years at baseline. We calculated energy density for overall diet (all solids and drinks) using food frequency questionnaires. During 12 years of follow-up, we documented 725 new-onset cases of diabetes among 21,919 participants without diabetes, cancer, or cardiovascular disease at baseline.

RESULTS

Baseline energy density (adjusted for age, sex, and baseline BMI) was higher in those who developed type 2 diabetes (mean 3.08 kJ/g [95% CI 3.03-3.13]) than in those who remained nondiabetic (3.01 kJ/g [3.00-3.02]) (P = 0.012). Energy density was positively associated with incident diabetes (odds ratio 1.21 per unit increase [95% CI 1.06-1.38]) adjusted for known risk factors. There was a 60% higher risk of diabetes (1.60 [1.19-2.16]) in the highest quintile of energy density (range 3.55-7.97 kJ/g) compared with the lowest quintile (1.04-2.43 kJ/g) in adjusted analysis.

CONCLUSIONS

This is the first large population-based prospective study to report that an energy-dense diet may be associated with increased risk of development of diabetes, independent of baseline obesity. The potential public health impact of a low-energy-dense diet on reducing the risk of diabetes deserves further study.

Fiber intake, not dietary energy density, is associated with subsequent change in BMI z-score among sub-groups of children

OBJECTIVE

Results from short-term studies demonstrate that energy density influences energy intake, but in children and adolescents the long-term effects of energy density and obesity development are sparse. We examined the longitudinal relationship between dietary energy density, fiber intake, and body weight change over 3 years among Danish children.

METHODS

Multiple regression analyses were performed using anthropometric and dietary data of 398 boys and girls (8-10 years) who were enrolled in 1997/1998 and followed up in 2000/2001. Validated 24-hour recall interviews were conducted in order to collect dietary energy intake. Overweight was defined as 1.05 SD, equivalent to the 85th percentile, of age- and sex-specific BMI z-score reference values.

RESULTS

An inverse association between fiber intake and subsequent excess weight gain was observed among the normal weight boys. In overweight boys, there was a direct association with excess weight gain. A high energy intake was associated with a higher weight gain among overweight than among normal-weight boys. No significant association between dietary energy density and subsequent excess weight change was seen. The prevalence of overweight increased from 27.1 to 29.9%. Mean Deltaz-score was +0.1 and +0.4 for boys and girls, respectively.

CONCLUSION

Dietary energy density was not associated with 3-year weight gain in boys and girls. Only energy and fiber intakes were related to weight gain, but in different ways for subgroups of normal-weight and overweight boys.