Exploring the changing association between parental and adolescent fruit and vegetable intakes, from age 10 to 30 years.

BACKGROUND: Adolescence is a pivotal developmental stage, where escalating rates of overweight and obesity have raised concerns about diet quality and its association with adverse health outcomes. Parents are known to have considerable influence on childhood diet, but how this influence changes as adolescents mature is unknown. This study investigates the association between parental fruit and vegetable (FV) intake and adolescent FV consumption, exploring how this changes across adolescence and when adolescents leave home. METHODS: Adolescents aged 10-30 years (n = 12,805) from the UK Household Longitudinal Study (UKHLS), and their parents, reported FV intakes every 2 years. Multilevel linear regression models were fitted to assess associations between parental and adolescent FV intakes, investigating interactions with age and living arrangement, and adjusting for sociodemographic covariates. RESULTS: Parental FV intake was positively associated with adolescent FV intake (ß = 0.20 [95%CI:0.19,0.22] portions/day), with the strength of this association lowest during early adolescence (10-14 years) and peaking at 17-18 years (ß = 0.30 [95%CI: 0.27,0.33] portions/day). When adolescents no longer lived in the parental home, the association of parental FV intake with adolescent FV consumption decreased, but a positive association was maintained up to age 30 years. CONCLUSIONS: Our findings emphasise the enduring effect of parental FV consumption on adolescent FV consumption, highlighting the potential for interventions to promote increased FV intake, acknowledging the lasting influence of parental diet, even beyond the confines of the parental home.

Total and temporal patterning of physical activity in adolescents and associations with mental wellbeing.

BACKGROUND: There is limited understanding of the extent to which differences in physical activity across the day and week may be associated with mental wellbeing. Such an understanding is needed for better targeting of interventions. In this study, we describe total and temporal patterning of physical activity across the week in adolescents (age 13-14y) and assess their prospective associations with mental wellbeing. METHODS: 1,983 13-14-year-old adolescent participants based in Cambridgeshire and Essex, recruited between 2016 and 2017 into the Get Others Active Trial provided data at baseline and 4 months. Physical activity was measured at baseline using wrist-worn accelerometers across different time segments (whole week, weekday schooltime, weekday out of school, and weekend), and operationalized as average movement-related acceleration for each time segment. Mental Wellbeing at baseline and 4 months was measured using the Warwick Edinburgh MentalWellbeing Scale. Associations between physical activity across different time segments (whole week, weekday schooltime, weekday out of school, and weekend) and mental wellbeing at 4 months were investigated using sex-stratified multi-level regression models, adjusted for covariates, and both adjusted and unadjusted for baseline mental wellbeing. RESULTS: Our analyses found positive associations between physical activity and mental wellbeing at 4 months, unadjusted for baseline wellbeing. Among girls, positive associations were shown when considering physical activity across the whole week 0.07 (95% CI, 0.03-0.12), and across all separate time periods studied: weekday schooltime 0.07 (95% CI, 0.02-0.11), weekday out-of-school time 0.07 (95% CI, 0.03-0.12), and weekend 0.07 (95% CI, 0.02-0.11). For boys, similar associations were observed for activity across the week 0.07 (95% CI, 0.03-0.11), during weekday schooltime 0.08 (95% CI, 0.04-0.12), and weekday out-of-school time 0.07 (95% CI, 0.03-0.11), but not the weekend 0.01 (95% CI, -0.03-0.05). For both girls and boys, associations were attenuated below significance after adjusting for baseline wellbeing. CONCLUSIONS: This longitudinal analysis showed positive associations between physical activity and later mental wellbeing in both male and female adolescents across most time segments. Higher physical activity throughout the week may be associated with better mental wellbeing in the adolescent population. Further research is required to understand determinants of change in wellbeing over time. TRIAL REGISTRATION: Registration Number: ISRCTN31583496. Registered: 18/02/2014.

Shorter sleep among adolescents is associated with lower fruit and vegetable consumption the following day.

BACKGROUND: Insufficient sleep has been associated with weight gain and metabolic dysregulation, with one suggested mechanism being through reduction in diet quality. Experimental evidence supports a causal effect of sleep timings on diet but this may not be applicable to a free-living adolescent population. In this analysis we use daily measures of sleep timings and diet quality, to examine the effect of sleep duration and timing on diet quality the following day among free-living adolescents. METHODS: The ROOTS study is a prospective cohort recruited from secondary schools in Cambridgeshire and Suffolk (UK). Participants (n = 815) at mean age 15.0y (SD 0.3y) completed a diet diary and wore a combined heart rate and accelerometer device over 4 consecutive days. Sleep duration and timing (midpoint) were derived from acceleration and heart rate traces, while daily energy density and fruit and vegetable intake were calculated from dietary data. Analyses were performed at day-level (1815 person-days). Multilevel random effects models were used to test associations between sleep each night and subsequent day diet, with daily sleep and diet measures nested within individuals and schools, and adjusted for day-level and individual-level confounding variables. RESULTS: Adolescents slept a mean of 7.88 hrs (SD 1.10) per night, reporting a mean energy density of 2.12 kcal/g (SD 0.48) and median energy-adjusted daily fruit and vegetable intake of 137.3 g (IQR 130.4). One hour shorter sleep duration was associated with lower intake of fruit and vegetables (-6.42 g, 95%CI -1.84, -10.99) the following day. An association with higher dietary energy density (0.016 kcal/g, 95%CI 0.034, -0.002) the following day was observed but did not reach statistical significance. Sleep timing was not associated with either fruit and vegetable intake (-2.52 g/d, 95%CI -7.66, 2.62) or dietary energy density (-0.001 kcal/g, 95%CI -0.022, 0.020). CONCLUSIONS: Our observational findings from a free-living adolescent population support the experimental evidence for a causal role of sleep on diet, with shorter sleep duration at night leading to a small decrease in diet quality the following day. These findings support experimental evidence to suggest inclusion of sleep duration as one component of interventions designed to improve diet quality and weight status in adolescents.

Recruitment and retention into longitudinal health research from an adolescent perspective: a qualitative study.

BACKGROUND: High quality longitudinal studies investigating changes in health behaviours over the transition into early adulthood are critical. However, recruiting and retaining adolescents is challenging. This study explored adolescents' perspectives of signing up to and continuing involvement in a hypothetical longitudinal health research study. METHODS: Forty-eight individuals (15-20y) participated in nine in-person focus groups about recruitment and retention in research. Participants were (a) school students in the last year of compulsory school (Year 11, 15-16y), (b) school/college students in Sixth Form (Year 13, 17-18y), (c) Further Education students studying after secondary education, but not higher education (16-18y) and (d) young adults not in education, employment, or training (18-20y) across England. Thematic analysis resulted in seven themes. RESULTS: Driving factors for sign-up included social connection e.g., joining with peer groups, personalised feedback, and incentives, primarily financial. Key barriers were lack of interest, the perception of commitment, and timing of recruitment. Young people preferred recruitment processes via social media with messages tailored to their motivations, monthly data collection of maximally 20-30 min, and hybrid data collection with some in-person contact with a consistent, non-judgemental researcher. The provision of autonomy, choice, and financial incentives were perceived to promote retention. CONCLUSIONS: Adolescent recruitment and retention strategies need to align with contemporary interests and motivations. Studies should involve adolescents early to develop a planned, systematic approach to participant sign-up and follow-up. Effective and ineffective recruitment and retention strategies should be reported as part of study findings. Future research should trial how perceived barriers to study engagement can be overcome.

How do short-term associations between diet quality and metabolic risk vary with age?

PURPOSE: Poor diet quality is one of the key contributors to poor cardiovascular health and associated morbidity and mortality. This study aimed to assess how the short-term associations between diet quality and metabolic risk factors change with age. METHODS: This longitudinal, observational study used data from the National Diet and Nutrition Survey (2008-2016) (n = 2024). Diet quality was measured using the Dietary Approaches to Stop Hypertension (DASH) index, fruit and vegetable (F&V) intake, and a F&V biomarker score. We assessed associations between measures of diet quality and a metabolic risk z score (generated from five metabolic risk factors) among those aged 11-60 years, and then tested effect modification by age group (adolescents 11-18 years, young adults 19-35 years, mid-aged adults 36-60 years). RESULTS: Analysis across all age groups showed inverse associations between standardised DASH index and metabolic risk z score of - 0.19 (95% CI - 0.26, - 0.11). These associations were moderated by age group, with strong associations seen in mid-aged adults: - 0.27 (95% CI - 0.39, - 0.16), but associations were significantly attenuated in young adults [- 0.10 (95% CI - 0.22, 0.01)] and adolescents [0.03 (95% CI - 0.05, 0.11)]. Similar results were found for F&V intake and F&V biomarker score. CONCLUSIONS: Short-term associations between diet quality and metabolic risk are not consistent across adolescent and young adult age groups, suggesting that mechanisms by which diet impacts on metabolic risk may be acting differently in younger age groups compared to adults. Further research is warranted using longitudinal study designs and replication in different populations to understand changes in determinants of cardiometabolic health with age.

Associations of early adulthood life transitions with changes in fast food intake: a latent trajectory analysis.

BACKGROUND: Early adulthood is a period of rapid personal development when individuals experience major life transitions (e.g. leaving the parental home, leaving education, beginning employment, cohabitation and parenthood). Changes in social and physical environments associated with these transitions may influence development of health-related behaviours. Consumption of fast food is one behaviour associated with poor diet and long-term health outcomes. In this study we assess how frequency of fast food consumption changes across early adulthood, and how major life transitions are associated with changes in fast food intake. METHODS: Data were collected across four waves of the Project EAT study, from mean age 14.9 (SD = 1.6) to mean age 31.1 (SD = 1.6) years. Participants reporting data at two or more waves were included (n = 2902). Participants reported past week frequency of eating food from a fast food restaurant and responded to questions on living arrangements, education and employment participation, and having children. To assess changes in fast food we developed a latent growth model incorporating an underlying trajectory of fast food intake, five life transitions, and time-invariant covariates. RESULTS: Mean fast food intake followed an underlying quadratic trajectory, increasing through adolescence to a maximum of 1.88 (SE 0.94) times/week and then decreasing again through early adulthood to 0.76 (SE 2.06) times/week at wave 4. Beginning full-time employment and becoming a parent both contributed to increases in fast food intake, each resulting in an average increase in weekly fast food intake of 0.16 (p < 0.01) times/week. Analysis of changes between pairs of waves revealed stronger associations for these two transitions between waves 1-2 (mean age 14.9-19.4 years) than seen in later waves. Leaving the parental home and beginning cohabitation were associated with decreases in fast food intake of - 0.17 (p = 0.004) and - 0.16 (p = 0.007) times/week respectively, while leaving full-time education was not associated with any change. CONCLUSIONS: The transitions of beginning full-time employment and becoming a parent were associated with increases in fast food intake. Public health policy or interventions designed to reduce fast food intake in young adults may benefit from particular focus on populations experiencing these transitions, to ameliorate their impact.

Cohabiting and becoming a parent: associations with changes in physical activity in the 1970 British cohort study.

BACKGROUND: We examined the association between family-related life events (cohabitation/marriage and becoming a parent) and change in physical activity. METHODS: Longitudinal data (n = 8045) from the 1970 British Cohort Study (30 and 34 years) were included. Life events (beginning cohabitation/marriage and becoming a parent) were reported and coded: 0 no, 1 yes, for each event occurring between 30 and 34 years. Participants reported frequency of participation in leisure-time physical activity at 30 and 34 years (Likert scale: mean change calculated ranging between - 4 and 4). Linear regression models were used to examine the association between life events and physical activity change (comparing individuals experiencing events between 30 and 34 years versus never experiencing the event - excluding participants that experienced previous events - with a final analysis sample of n = 3833 in parenthood analysis; n = 1137 in cohabitation analysis). Interaction terms were used to analyse combined parenthood and cohabitation status. Analyses were adjusted for level of education achieved, ethnicity, country of origin and other life events. ANCOVA was used to examine associations between change in physical activity and child age. RESULTS: Compared to remaining without children, becoming a parent was associated with a greater reduction in physical activity among men [ß:-0.234(95%CI:-0.396 to - 0.072)] but not women [0.126(- 0.048;0.301)]. No associations were found between cohabitation and physical activity. Men who became fathers both while cohabitating [- 0.201(- 0.383;-0.020)] and without cohabiting [- 0.937(- 1.623;-0.250)] experienced greater physical activity declines than those remaining single and without children; the decline was greatest among non-cohabiting fathers. These associations did not differ by child age. CONCLUSIONS: Parenthood appears to differentially impact physical activity for men and women; this association also differs by cohabitation status. Parenthood appears to be most detrimental to physical activity levels among men. Interventions for physical activity could target new or soon-to-be parents, especially fathers. Further analyses with device-measured physical activity data would be valuable to advance understanding of these associations.

Change in physical activity from adolescence to early adulthood: a systematic review and meta-analysis of longitudinal cohort studies.

OBJECTIVE: To systematically review and meta-analyse how physical activity (PA) changes from adolescence to early adulthood (13-30 years). DATA SOURCES: Seven electronic databases were searched: Medline, Embase, PsycInfo, SCOPUS, ASSIA, SPORTdiscus and Web of Science. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: English-language, longitudinal studies (from 01/1980 to 01/2017) assessing PA ≥twice, with the mean age of ≥1 measurement in adolescence (13-19 years) and ≥1 in young adulthood (16-30 years) were included. Where possible, data were converted to moderate-to-vigorous physical activity (MVPA) min/day, and meta-analyses were conducted between weighted mean differences (WMDs) in adolescence and adulthood. Heterogeneity was explored using meta-regression. RESULTS: Of 67 included studies, 49 were eligible for meta-analysis. PA was lower during adulthood than adolescence WMD (95% CI) -5.2 (-7.3 to -3.1) min/day MVPA over mean (SD) 3.4 (2.6) years; heterogeneity was high (I2 >99.0%), and no predictors explained this variation (all p>0.05). When we restricted analysis to studies with data for males (n=29) and females (n=30) separately, there were slightly larger declines in WMD (-6.5 (-10.6 to -2.3) and -5.5 (-8.4 to -2.6) min/day MVPA) (both I2 >99.0%). For studies with accelerometer data (n=9), the decline was -7.4 (-11.6 to -3.1) and longer follow-up indicated more of a decline in WMD (95% CI) (-1.9 (-3.6 to -0.2) min/day MVPA), explaining 27.0% of between-study variation. Of 18 studies not eligible for meta-analysis, nine statistically tested change over time: seven showed a decline and two showed no change. CONCLUSION: PA declines modestly between adolescence and young adulthood. More objective longitudinal PA data (eg, accelerometry) over this transition would be valuable, as would investigating how PA change is associated with contemporaneous social transitions to better inform PA promotion interventions. REGISTRATION: PROSPERO ref:CRD42015030114.

Changes in diet through adolescence and early adulthood: longitudinal trajectories and association with key life transitions.

BACKGROUND: Early adulthood is a period associated with poor diet and rapid weight gain. This is also an age of transition, including environmental, social and lifestyle changes which may be associated with changes in diet. We assess longitudinal associations between four early adulthood life transitions (leaving home, leaving education, entering employment, and cohabitation) and changes in consumption of fruit, vegetables, confectionery and sugar-sweetened beverages (SSBs). METHODS: Participants (n = 1100) from the Norwegian Longitudinal Health Behaviour Study, reported data on diet and life transitions on up to eight occasions from age 14 to age 30. Diet data were self-reported in response to questions on intake of fruit, vegetables, confectionery and sugar-sweetened beverages. Growth models were developed to describe changing intake of each of the four diet indicators with age. Fixed-effects regression models assessed associations between the four life transitions and within-individual changes in diet indicators, with adjustment for the remaining transitions and parenthood. RESULTS: Diet indicators showed quadratic trajectories with age: fruit and vegetable intakes declined from age 14 to ages 23 and 21 respectively, before increasing to age 30. SSB and confectionery intakes increased to age 18, before subsequently decreasing. Leaving the parental home was associated with a decrease in fruit intake of - 0.54 times/week (95% confidence interval (95%CI): -0.87;-0.22) and vegetable intake of - 0.43 times/week (95%CI: -0.70;-0.15). Leaving education was associated with increases in confectionery (0.33 times/week (95%CI: 0.04;0.62)) and SSB intakes (0.49 times/week (95%CI: 0.10;0.87). CONCLUSIONS: Leaving home and leaving education are associated with negative changes in diet and may present opportunities for effective diet and obesity intervention. Further study of these transitions is needed to understand the mechanisms mediating associations between life transitions and changes in diet.

Diet quality and depressive symptoms in adolescence: no cross-sectional or prospective associations following adjustment for covariates.

OBJECTIVE: Adolescence is a critical period for development of depression and understanding of behavioural risk factors is needed to support appropriate preventive strategies. We examined associations between adolescent diet quality and depressive symptoms, cross-sectionally and prospectively, in a large community cohort, adjusting for behavioural and psychosocial covariates. DESIGN: Prospective community-based cohort study (ROOTS). SETTING: Secondary schools in Cambridgeshire and Suffolk, UK. SUBJECTS: Study participants (n 603) who completed 4 d diet diaries at age 14 years and reported depressive symptoms (Moods and Feelings Questionnaire (MFQ)) at 14 and 17 years of age. RESULTS: Diet data were processed to derive a Mediterranean diet score (MDS) and daily servings of fruit and vegetables, and fish. At age 14 years, a negative association between fruit and vegetable intake and MFQ score was seen in the unadjusted cross-sectional regression model (ß=-0·40; 95 % CI -0·71,-0·10), but adjustment for behavioural covariates, including smoking and alcohol consumption, attenuated this association. Fish intake and MDS were not cross-sectionally associated with MFQ score. No prospective associations were found between MDS, fruit and vegetable intake or fish intake and later MFQ score. CONCLUSIONS: Diet quality was not associated with depressive symptoms in mid-adolescence. Previously reported associations in this age range may be due to confounding. Further longitudinal studies are needed that investigate associations between adolescent diet and depression across different time frames and populations, ensuring appropriate adjustment for covariates.

Current and future cardiovascular disease risk assessment in the European Union: an international comparative study.

Background: Risk assessment is central to primary prevention of cardiovascular disease (CVD), but there remains a need to better understand the use of evidence-based interventions in practice. This study examines: (i) the policies and guidelines for risk assessment in Europe, (ii) the use of risk assessment tools in clinical practice and (iii) the barriers to, and facilitators of, risk assessment. Methods: Data were collected from academics, clinicians and policymakers in an online questionnaire targeted at experts from all European Union member states, and in 8 in-depth country case studies that were developed from a targeted literature review and 36 interviews. Results: The European Society of Cardiology (ESC) produces European guidelines for CVD risk assessment and recommends the Systematic COronary Risk Evaluation tool, which is the most widely used risk assessment tool in Europe. The use of risk assessment tools is variable. Lack of time and resources are important barriers. Integrating risk assessment tools into clinical systems and providing financial incentives to carry out risk assessments could increase implementation. Novel biomarkers would need to be supported by evidence of their clinical effectiveness and cost-effectiveness to be introduced in clinical practice. These findings were consistent across Europe. Conclusions: Efforts to improve the assessment of CVD risk in clinical practice should be carried out by or in collaboration with, the ESC. Increasing the use of existing risk assessment tools is likely to offer greater gains in primary prevention than the development of novel biomarkers.

Change in diet in the period from adolescence to early adulthood: a systematic scoping review of longitudinal studies.

BACKGROUND: Late adolescence to early adulthood is a period of lifestyle change and personal development which may influence dietary behaviour. Understanding dietary trajectories across this age range may help in targeting interventions appropriately. This scoping review aimed to assess how longitudinal change in diet is conceptualised and measured between the ages of 13 to 30. METHODS: We searched Medline, SCOPUS, Embase, PsycInfo (EBSCO), ASSIA, Sportdiscus, and Web of Science Core Collection (January 2016) using search terms combining diet outcomes, longitudinal methods and indicators of adolescent or young adult age. Titles and abstracts were screened and data extracted following published guidelines for scoping reviews. Data were analysed to summarize key data on each study and map availability of longitudinal data on macronutrients and food groups by age of study participants. RESULTS: We identified 98 papers reporting on 40 studies. Longitudinal dietary data were available on intake of energy, key macronutrients and several food groups, but this data had significant gaps and limitations. Most studies provided only two or three waves of data within the age range of interest and few studies reported data collected beyond the early twenties. A range of dietary assessment methods were used, with greater use of less comprehensive dietary assessment methods among studies reporting food group intakes. CONCLUSION: Despite limited availability of longitudinal data to aid understanding of dietary trajectories across this age range, this scoping review identified areas with scope for further evidence synthesis. We identified a paucity of longitudinal data continuing into the mid and late twenties, variability in (quality of) dietary assessment methods, and a large variety of macronutrients and food groups studied. Advances in dietary assessment methodologies as well as increased use of social media may facilitate new data collection to further understanding of changing diet across this life stage.

Changes in diet from age 10 to 14 years and prospective associations with school lunch choice.

BACKGROUND: There is limited evidence on how diet changes over the transition from primary to secondary school. In this study we investigated changes in diet from age 10 (2007) to age 14 years (2011) and the contribution of school-time consumption and school lunch choice to such changes. METHODS: The 351 participants with dietary data (4 day food record) available at baseline (age 10 years) and follow-up (age 14 years) were included. Multi-level regression models were fitted for absolute or change in food and nutrient intake, cross-classified by primary and secondary school attended as appropriate, with adjustment for covariates and mis-reporting. RESULTS: From age 10 to age 14 years, children decreased energy intake from sugars (-2.6% energy (%E)) (standard error (SE) 0.44) and from saturated fats (-0.54%E (SE 0.18)), decreased fruit (-3.13 g/MJ (SE 1.04)) and vegetables (-1.55 g/MJ (SE 0.46)) consumption and increased sugar sweetened beverage (SSB) (4.66  g/MJ (SE 1.87)) and fries (1.31  g/MJ (SE 0.39)) consumption. Intake of snack foods, SSBs, and fries, but also fruits and vegetables was higher outside school hours. Prospective change from non-school lunch to school lunch, compared to maintaining non-school lunch consumption, was associated with decreased consumption of savoury snacks (-8.32 g/day (SE 2.03)), increased consumption of fries (12.8 g/day (SE 4.01)) and decreased consumption of fruit (-25.16 g/day (SE 11.02)) during school hours. CONCLUSIONS: Changes in diet from age 10 to age 14 years differed within and outside of school hours. Consumption of a school lunch, compared to lunch obtained elsewhere, was associated with negative as well as positive changes in diet, suggesting that any efforts to encourage school lunch take-up need to be accompanied by further efforts to improve school lunch provision to meet nutritional guidelines.

The Cognitive and Behavioural Impact of Alcohol Promoting and Alcohol Warning Advertisements: An Experimental Study.

AIMS: To assess the immediate effect of alcohol promoting and alcohol warning advertisements on implicit and explicit attitudes towards alcohol and on alcohol seeking behaviour. METHODS: We conducted a between-participants online experiment in which participants were randomly assigned to view one of three sets of advertisements: (a) alcohol promoting, (b) alcohol warning, or (c) unrelated to alcohol. A total of 373 participants (59.5% female) aged 18-40 (M = 28.03) living in the UK were recruited online through a research agency. Positive and negative implicit attitudes and explicit attitudes towards alcohol were assessed before and after advertisements were viewed. Alcohol seeking behaviour was measured by participants' choice of either an alcohol-related or non-alcohol-related voucher offered ostensibly as a reward for participation. Self-reported past week alcohol consumption was also recorded. RESULTS: There were no main effects on any of the outcome measures. In heavier drinkers, viewing alcohol promoting advertisements increased positive implicit attitudes (standardized beta = 0.15, P = 0.04) and decreased negative implicit attitudes (standardized beta = -0.17, P = 0.02). In heavier drinkers, viewing alcohol warning advertisements decreased negative implicit attitudes (standardized beta = -0.19, P = 0.01). CONCLUSIONS: Viewing alcohol promoting advertisements has a cognitive impact on heavier drinkers, increasing positive and reducing negative implicit attitudes towards alcohol. Viewing alcohol warning advertisements reduces negative implicit attitudes towards alcohol in heavier drinkers, suggestive of a reactance effect.

For debate: a new wave in public health improvement.

The rising burden of chronic disease poses a challenge for all public health systems and requires innovative approaches to effectively improve population health. Persisting inequalities in health are of particular concern. Disadvantage because of education, income, or social position is associated with a larger burden of disease and, in particular, multimorbidity. Although much has been achieved to enhance population health, challenges remain, and approaches need to be revisited. In this paper, we join the debate about how a new wave of public health improvement might look. We start from the premise that population health improvement is conditional on a health-promoting societal context. It is characterised by a culture in which healthy behaviours are the norm, and in which the institutional, social, and physical environment support this mindset. Achievement of this ambition will require a positive, holistic, eclectic, and collaborative effort, involving a broad range of stakeholders. We emphasise three mechanisms: maximisation of the value of health and incentives for healthy behaviour; promotion of healthy choices as default; and minimisation of factors that create a culture and environment which promote unhealthy behaviour. We give examples of how these mechanisms might be achieved.

Exposure of children and adolescents to alcohol marketing on social media websites.

AIMS: In 2011, online marketing became the largest marketing channel in the UK, overtaking television for the first time. This study aimed to describe the exposure of children and young adults to alcohol marketing on social media websites in the UK. METHODS: We used commercially available data on the three most used social media websites among young people in the UK, from December 2010 to May 2011. We analysed by age (6-14 years; 15-24 years) and gender the reach (proportion of internet users who used the site in each month) and impressions (number of individual pages viewed on the site in each month) for Facebook, YouTube and Twitter. We further analysed case studies of five alcohol brands to assess the marketer-generated brand content available on Facebook, YouTube and Twitter in February and March 2012. RESULTS: Facebook was the social media site with the highest reach, with an average monthly reach of 89% of males and 91% of females aged 15-24. YouTube had a similar average monthly reach while Twitter had a considerably lower usage in the age groups studied. All five of the alcohol brands studied maintained a Facebook page, Twitter page and YouTube channel, with varying levels of user engagement. Facebook pages could not be accessed by an under-18 user, but in most cases YouTube content and Twitter content could be accessed by those of all ages. CONCLUSION: The rise in online marketing of alcohol and the high use of social media websites by young people suggests that this is an area requiring further monitoring and regulation.

Youth exposure to alcohol advertising on television in the UK, the Netherlands and Germany.

BACKGROUND: Exposure of young people to alcohol advertising is a risk factor for underage drinking. This study assessed youth exposure to television alcohol advertising in the UK, the Netherlands and Germany, from December 2010 to May 2011. METHODS: A negative binomial regression model predicted number of alcohol advertisements from the proportion of the television viewership in each age group. This allowed comparison of alcohol advertisement incidence for each youth age category relative to an adult reference category. RESULTS: In the UK, those aged 10-15 years were significantly more exposed to alcohol advertisements per viewing hour than adults aged ≥ 25 years [incidence rate ratio (IRR) = 1.11; 95% confidence interval (95% CI): 1.06, 1.18; P < 0.01]; in the Netherlands, those aged 13-19 years were more exposed per viewing hour than adults aged ≥ 20 years (IRR = 1.29; 95% CI: 1.19, 1.39; P < 0.01). Conversely, in Germany, those aged 10-15 years were less exposed to alcohol advertisements than adults aged ≥ 25 years (IRR = 0.79; 95% CI: 0.73, 0.85; P < 0.01). In each country, young children (aged 4-9 years in the UK and Germany, 6-12 years in the Netherlands) were less exposed than adults. CONCLUSION: Adolescents in the UK and the Netherlands, but not Germany, had higher exposure to television alcohol advertising relative to adults than would be expected from their television viewing. Further work across a wider range of countries is needed to understand the relationship between national policies and youth exposure to alcohol advertising on television.

Changes in diet quality across life transitions from adolescence to early adulthood: a latent growth analysis.

Background: Adolescence to early adulthood is a period of multiple education-, employment- and family-related life transitions. Changing resources and food environments within the context of these transitions could contribute to significant changes in diet, which persist into later adulthood. This study investigated diet quality trajectories from age 15 to 31 years and changes in diet quality associated with life transitions, by sex. Methods: Data from the Project EAT (Eating and Activity in Teens and Young Adults) study were used to examine diet quality among a longitudinal cohort (n=2,524) across four waves (mean ages of 15, 19, 25 and 31 years). Diet quality was evaluated using the DASH (Dietary Approaches to Stop Hypertension) index. Life transitions were assessed by changes in life circumstances between pairs of waves, including leaving the parental home, leaving full-time education, beginning full-time employment, cohabitating with a partner, and becoming a parent. Average within-person changes in DASH scores were analysed by sex-specific latent growth models, incorporating underlying growth trajectories, five life transitions and baseline socio-demographic characteristics. Results: Both sexes followed a quadratic trajectory of DASH scores, showing decreases in diet quality from waves 1 to 2 followed by increases until wave 4. Compared to females, males had worse diet quality at wave 1, and this sex difference widened at wave 4. Leaving the parental home between waves 1 and 2 was associated with transient decreases in diet quality at wave 2 only for males. For females, cohabitating with a partner and becoming a parent between waves 3 and 4 were respectively related to decreases and increases in diet quality at wave 4. Leaving full-time education and starting full-time employment respectively had long-term negative and positive associations with diet quality for both sexes. Conclusions: Diet quality remained suboptimal throughout adolescence but to some extent improved across early adulthood. A sex-sensitive approach in public health policy is welcome for addressing sex differences in diet quality and dietary changes associated with family-related life transitions. Targeted dietary interventions are beneficial for young people who leave their parental home early or who do not enter into a structured school or workplace environment.

A longitudinal study of lifestyle behaviours in emerging adulthood and risk for symptoms of depression, anxiety, and stress.

BACKGROUND: Little research has examined how lifestyle behaviours cluster together to contribute to mental health outcomes. The current study aimed to identify latent classes of emerging adult lifestyle behaviours (diet, physical activity, sedentary time, smoking, alcohol, cannabis, and other drug use) at age 20 years and their associations with depression, anxiety, and stress symptoms at age 22 and 27 years. METHODS: Participants were 616 emerging adults enrolled in the Raine Study. Lifestyle classes at baseline were identified using latent class analysis. Longitudinal associations between latent class membership and risk of depression, anxiety, and stress symptoms were examined using logistic regression models. RESULTS: Three lifestyle classes were identified: Class 1 (healthier pattern, n = 399 [64.8 %]), Class 2 (predominantly female, high substance-use, low physical activity pattern, n = 121 [19.6 %]), and Class 3 (predominantly male, high substance-use, poor diet pattern, n = 96 [15.6 %]). Following adjustment, Class 2 were at a higher risk of depression, anxiety, and stress symptoms at age 22 years, and a higher risk of anxiety and stress symptoms at age 27 years, compared to Class 1. LIMITATIONS: This study was limited by reliance on self-report data, lack of available indicators for parental socioeconomic status, and some measurement inconsistencies across variables. Adherence to lifestyle clusters over time was not assessed. CONCLUSIONS: Latent classes of lifestyle behaviours were identified among emerging adults, and differences in mental health outcomes were found among the classes at two prospective time points. Future research and prevention strategies for common mental disorders should target emerging adults and focus on lifestyle patterns.

Device-measured sleep onset and duration in the development of depressive symptoms in adolescence.

BACKGROUND: Sleep deprivation in adolescence is increasing in prevalence and may be linked to subsequent depression. Findings regarding associations between sleep duration, sleep onset time, and the development of depressive symptoms over time in adolescents are mixed, and rely on subjective measures of sleep. METHODS: Sleep onset and duration were assessed using a combined heart rate monitor and accelerometer and self-report in 688 participants from the ROOTS study at age 15. Participants reported depressive symptoms at ages 14.5, 16, and 17.5, using the Mood and Feelings Questionnaire. Latent growth curve modelling was used to model development of depressive symptoms and test associations with baseline sleep onset and duration. RESULTS: Cross-sectionally, falling asleep later and shorter sleep duration were both associated with higher depressive symptoms in males and females, using both device-measured and self-reported sleep. There were no longitudinal associations between baseline sleep duration and change in depressive symptoms. A later sleep onset-time was associated with a decrease in depressive symptoms over time, in females only, using device-measured sleep only. LIMITATIONS: The current sample was more economically advantaged and ethnically white than the UK average, and with lower MFQ symptoms than the original cohort, which may reduce generalisability. CONCLUSIONS: Adolescents who fall asleep later or sleep less have higher levels of depressive symptoms cross-sectionally, but do not show increases in depressive symptoms over time. Interventions targeting sleep onset and duration in adolescence may improve mental health in the short-term but the possibility of reverse causality should be explored further.