Background: Influences on diet quality during the transition from adolescence to adulthood are understudied. Objective: This study examined association of 3 diet-quality indicators-Healthy Eating Index-2010 (HEI), Whole Plant Foods Density (WPF), and Empty Calories (EC; the percentage of calories from discretionary solid fat, added sugar and alcohol)-with lifestyle behaviors, baseline weight status, and sociodemographic characteristics in US emerging adults. Design: Data come from the first 4 waves (annual assessments) of the NEXT Plus Study, a population-based cohort of 10th graders enrolled in 2010 (n = 566). At each assessment, participants completed 3 nonconsecutive 24-h diet recalls, wore accelerometers for 7 d, and self-reported meal practices and sedentary behaviors. Self-reported sociodemographic characteristics were ascertained at baseline. Generalized estimating equations examined associations of time-varying diet quality with baseline weight status and sociodemographic characteristics and time-varying lifestyle behaviors.Results: Diet quality improved modestly from baseline (mean 6 SE: HEI, 44.07 6 0.53; WPF, 1.24 6 0.04; and EC, 35.66 6 0.55) to wave 4 for WPF (1.44 6 0.05, P , 0.001) and EC (33.47 6 0.52, P , 0.001), but not HEI (45.22 6 0.60). In longitudinal analyses, higher HEI and lower EC scores were observed in Hispanic compared with white participants. Better diet quality was associated with greater moderate-to-vigorous physical activity, more frequent breakfast and family meals, less frequent fast food and meals during television viewing, and shorter durations of television viewing, gaming, and online social networking. Diet-quality indicators were not consistently associated with time-varying physical inactivity, baseline weight status, or sociodemographic characteristics. Conclusions: Diet quality of emerging adults in the US remained suboptimal, but some aspects improved marginally over the 4-y study period. Meal contexts and sedentary behaviors may represent important intervention targets. There is substantial room for improvement in diet quality in all sociodemographic subgroups. This trial was registered at clinicaltrials.gov as NCT01031160.

Both overall diet quality and macronutrient distribution were associated with more optimal glycemic control. Associations were more consistent for CGM variables obtained concurrently with dietary intake than for biomarkers of longer-term glycemic control. These findings suggest that glycemic control may be improved by increasing intake of high-fiber, low glycemic-index, carbohydrate-containing foods. This trial was registered at clinicaltrials.gov as NCT00999375.

ObjectivesTo examine nine-year trends and relationships regarding misperceptions of body size and dieting for weight loss among adolescents from 24 countries, and explore the influence of country-level overweight prevalence.MethodsSocio-demographic characteristics, body size perception, and dieting for weight loss were assessed in the Health Behaviour in School-aged Children survey conducted in 24 countries cross-sectionally at three time points (2001/02, 2005/06, 2009/10). Logistic regression models examined change over time in overestimation of body size in non-overweight adolescents, underestimation of body size in overweight adolescents, dieting for weight loss in non-overweight and overweight adolescents, and relationships between body size perception and dieting. Analyses were stratified by weight status and sex. Covariates included country-level overweight prevalence, family affluence, and country level of development. Body mass index was only included in models examining dieting for weight loss.ResultsCountry-level overweight prevalence increased over time (11.6% to 14.7%). Compared to Time 1, overweight adolescents had greater odds of body size underestimation at Time 3 (OR=1.68 for girls, OR=1.10 for boys), while non-overweight adolescents had lower odds of body size overestimation at Time 3 (OR=0.87 for girls, OR=0.89 for boys). Controlling for country-level overweight prevalence attenuated these relationships. Compared to Time 1, overweight and non-overweight boys were 10% more likely to diet at Time 3, while overweight and non-overweight girls were 19% and 16%, respectively, less likely to diet at Time 3. Controlling for country-level overweight prevalence did not impact trends in dieting for weight loss. Additionally, the association of self-perceived overweight with increased odds of dieting diminished over time.ConclusionsBody size perceptions among adolescents may have changed over time concurrent with shifts in country-level body weight. However, controlling for country-level overweight prevalence did not impact trends in dieting for weight loss, suggesting a potentially stronger impact of social comparison on weight-related perceptions than on behavior.

BackgroundDiets of U.S. adolescents and adults do not meet recommendations, increasing risk of chronic disease. This study examined trajectories and predictors of eating behaviors in U.S. youth from age 16–20 years, and evaluated longitudinal associations of eating behaviors with weight outcomes.MethodsData come from the first four waves (years) of the NEXT Generation Health Study, a nationally representative cohort of U.S. students in 10th grade during the 2009–2010 school year (n = 2785). Annual surveys queried frequency of food group intake (times/day of fruit and vegetables, whole grains, sugar-sweetened soda, sweet and salty snacks), and meal practices (days/week of breakfast, family meals, fast food, and television during meals). Body mass index (BMI, kg/m2) was calculated from self-reported height and weight. Adjusted generalized estimating equations and linear mixed models with multiple imputation for missing data estimated eating behavior trajectories overall and by baseline weight status (normal weight = 5 ≤ BMI%ile < 85, overweight = 85 ≤ BMI%ile < 95, obese = BMI%ile ≥ 95), accounting for the complex sampling design. Separate GEE models estimated longitudinal associations of food group frequencies with meal practices and of BMI with eating behaviors.ResultsEating behaviors tracked strongly from wave 1–4 (residual intraclass correlation = 41 % - 51 %). Across all baseline weight categories, frequency of food group intake and meal practices decreased over time, except for fast food, which remained stable. Fruit/vegetable intake frequency was associated positively with family meals (β ± SE = 0.33 ± 0.05) and breakfast (0.18 ± 0.03), and inversely with fast food (−0.31 ± 0.04), while whole grain intake frequency was associated positively with family meals (0.07 ± 0.02), television meals (0.02 ± 0.009) and breakfast (0.04 ± 0.01). Soda and snacks were positively associated with television meals (0.08 ± 0.008 and 0.07 ± 0.009, respectively) and fast food (0.24 ± 0.02 and 0.20 ± 0.03, respectively), while soda was inversely associated with breakfast frequency (−0.05 ± 0.01). Time-varying BMI was unrelated to eating behaviors other than an inverse association with time-varying snacks (−0.33 ± 0.12).ConclusionsStrong tracking over time supports the importance of early establishment of health-promoting eating behaviors in U.S. adolescents. Findings suggest meal practices may be important intervention targets. Lack of evidence for hypothesized associations of BMI and eating behaviors indicates the need for research confirming these findings using more precise measures of dietary intake.Electronic supplementary materialThe online version of this article (doi:10.1186/s12966-015-0298-x) contains supplementary material, which is available to authorized users.

Pregnancy weight gain may lead to long-term increases in maternal BMI for some women. The objective of this study was to examine maternal body weight change 1y–2y postpartum, and to compare classifications of 2y weight retention with and without accounting for 1y–2y weight gain. Early pregnancy body weight (EPW, first trimester) was measured or imputed, and follow-up measures obtained before delivery, 1 year postpartum (1y) and 2 years postpartum (2y) in an observational cohort study of women seeking prenatal care in several counties in upstate New York (n = 413). Baseline height was measured; demographic and behavioral data were obtained from questionnaires and medical records. Associations of 1y–2y weight change (kg) and 1y–2y weight gain (≥2.25 kg) with anthropometric, socioeconomic, and behavioral variables were evaluated using linear and logistic regressions. While mean ± SE 1y–2y weight change was 0.009 ± 4.6 kg, 1y–2y weight gain (≥2.25 kg) was common (n = 108, 26%). Odds of weight gain 1y–2y were higher for overweight (ORadj = 2.63, CI95% = 1.43–4.82) and obese (ORadj = 2.93, CI95% = 1.62–5.27) women than for women with BMI <25. Two year weight retention (2y–EPW ≥2.25 kg) was misclassified in 38% (n = 37) of women when 1y–2y weight gain was ignored. One year weight retention (1YWR) (1y–EPW) was negatively related to 1y–2y weight change (βadj ± SE = −0.28 ± 0.04, P < 0.001) and weight gain (≥2.25 kg) (ORadj = 0.91, CI95% = 0.87–0.95). Relations between 1y weight retention and 1y–2y weight change were attenuated for women with higher early pregnancy BMI. Weight change 1y–2y was predicted primarily by an inverse relation with 1y weight retention. The high frequency of weight gain has important implications for classification of postpartum weight retention.