Advantageous early-life environments cushion the genetic risk for ischemic heart disease.

In one of the first papers on the impact of early-life conditions on individuals' health in older age, Barker and Osmond [Lancet, 327, 1077-1081 (1986)] show a strong positive relationship between infant mortality rates in the 1920s and ischemic heart disease in the 1970s. We merge historical data on infant mortality rates to 370,000 individual records in the UK Biobank using information on local area and year of birth. We replicate the association between the early-life infant mortality rate and later-life ischemic heart disease in our sample. We then go "beyond Barker," by showing considerable genetic heterogeneity in this association that is robust to within-area as well as within-family analyses. We find no association between the polygenic index and heart disease in areas with the lowest infant mortality rates, but a strong positive relationship in areas characterized by high infant mortality. These findings suggest that advantageous environments can cushion one's genetic disease risk.

The ultra-processed food content of school meals and packed lunches in the UK, 2008-17: a pooled cross-sectional study.

BACKGROUND: British children have the highest ultra-processed food (UPF) intake in Europe, concerning as UPF is linked to adverse health outcomes. Schools are a potential setting for intervention, yet the rate of UPFs consumed at schools is currently unknown. This study aimed to describe the UPF content of school food in the UK and to explore differences in UPF content by meal type (school meals and packed lunches [food from home]) and children's household income. METHODS: We performed a pooled cross-sectional analysis of 1895 primary school children (aged 4-11 years) and 1408 secondary school children (aged 11-18 years) using data from the UK's National Diet and Nutrition Survey (from Feb, 2008, to June, 2017). Student's meal type was recorded using food diaries. UPF intake was defined using the NOVA food classification system. Income was measured through interview. We used quantile regression models to assess the association between meal type and lunchtime UPF intake (by both the percentage of calories and weight). We stratified models by school phase (primary or secondary) and interacted meal type with income. FINDINGS: The majority of schoolchildren's lunch was defined as UPFs, with secondary school children having higher median intakes of UPFs than primary school children (78% kcal [IQR 58-95] vs 73% kcal [55-86). School meals were associated with a lower median UPF intake than packed lunches for primary school children (61% kcal [IQR 44-75] vs 81% kcal [71-91]) and for secondary school children (70% kcal [IQR 48-89] vs 84% kcal [65-99]). Results were similar when UPFs were analysed as a percentage of the total weight of lunch. Overall, income was inversely associated with UPF lunch content. However, in primary school children, there was no significant association between percentage of UPF content of school meals by weight. INTERPRETATION: In the first nationally representative study, we showed that UK school children have a high intake of UPFs at lunch. UPF intake was increased in children who consumed packed lunches, secondary school children, and children of a lower income. School meal procurement policies must be re-evaluated to protect children from high UPF intake. FUNDING: This study was funded by the National Institute for Health Research School for Public Health Research.

Dietary quality of school meals and packed lunches: a national study of primary and secondary schoolchildren in the UK.

OBJECTIVE: School lunches represent a key opportunity to improve diets and health of schoolchildren. No recent nationally representative studies have examined the nutritional differences between school meals and packed lunches in the UK. This study aimed to characterise and compare the nutritional quality of school meals and packed lunches among primary and secondary school-age children. DESIGN: A pooled cross-sectional analysis of the UK's National Diet and Nutrition Survey (2008-2017). SETTING: United Kingdom. PARTICIPANTS: 3001 children (aged 4-16 years) who completed a 3/4-d food diary which recorded meal type (school meal/packed lunch). Multivariable logistic regression models assessed associations of meeting food and nutrient recommendations by meal type. Analyses were stratified by academic key stages (KS). RESULTS: KS-1 (4-7 years) and 2 (8-11 years) children consuming school meals were more likely to meet minimum recommendations for vegetables, protein-rich foods and fibre, and not exceed maximum recommendations for salt, savoury and sweet snacks compared with pupils consuming packed lunches. However, in KS-3 (12-14 years) and 4 (14-16 years), these effects were reduced. As children aged, the median weight of fruits, vegetables, protein-rich foods and dairy products consumed typically decreased for both school meals and packed lunches, and generally an increasing proportion of school meals contained sweet and savoury snacks. CONCLUSION: These findings suggest school meals are nutritionally superior to packed lunches but are not yet optimal. Quality declined at higher KS. Actions to improve lunches of primary and secondary schoolchildren across the UK are needed, with attention to KS-3 and 4 in secondary schools.

Field validity and spatial accuracy of Food Standards Agency Food Hygiene Rating scheme data for England.

BACKGROUND: The study aimed to evaluate the validity and spatial accuracy of the Food Standards Agency Food Hygiene Rating online data through a field audit. METHODS: A field audit was conducted in five Lower Layer Super Output Areas (LSOAs) in the North East of England. LSOAs were purposively selected from the top and bottom quintiles of the Index of Multiple Deprivation and from urban and rural areas. The FHRS data validity against the field data was measured as Positive Predictive Values (PPV) and sensitivity. Spatial accuracy was evaluated via mean difference in straight line distances between the FHRS coordinates and the field coordinates. RESULTS: In all, 182 premises were present in the field, of which 162 were in the FHRS data giving a sensitivity of 89%. Eight outlets recorded in the FHRS data were absent in the field, giving a PPV of 95%.The mean difference in the geographical coordinates of the field audit compared to the FHRS was 110 m, and <100 m for 77% of outlets. CONCLUSIONS: After an evaluation of the validity and spatial accuracy of the FHRS data, the results suggest that it is a useful dataset for surveillance of the food environment and for intervention evaluation.

Is the healthy start scheme associated with increased food expenditure in low-income families with young children in the United Kingdom?

BACKGROUND: Healthy Start is a food assistance programme in the United Kingdom (UK) which aims to provide a nutritional safety-net and enable low-income families on welfare benefits to access a healthier diet through the provision of food vouchers. Healthy Start was launched in 2006 but remains under-evaluated. This study aims to determine whether participation in the Healthy Start scheme is associated with differences in food expenditure in a nationally representative sample of households in the UK. METHODS: Cross-sectional analyses of the Living Costs and Food Survey dataset (2010-2017). All households with a child (0-3 years) or pregnant woman were included in the analysis (n = 4869). Multivariable quantile regression compared the expenditure and quantity of fruit and vegetables (FV), infant formula and total food purchases. Four exposure groups were defined based on eligibility, participation and income (Healthy Start Participating, Eligible Non-participating, Nearly Eligible low-income and Ineligible high-income households). RESULTS: Of 876 eligible households, 54% participated in Healthy Start. No statistically significant differences were found in FV or total food purchases between participating and eligible non-participating households, but infant formula purchases were lower in Healthy Start participating households. Ineligible higher-income households had higher purchases of FV. CONCLUSION: This study did not find evidence of an association between Healthy Start participation and FV expenditure. Moreover, inequalities in FV purchasing persist in the UK. Higher participation and increased voucher value may help to improve programme performance and counteract the harmful effects of poverty on diet.

Protecting energy intakes against income shocks.

Whether and how changes in economic circumstances or household income affect individuals' diet and nutritional intakes is of substantial interest for policy purposes. This paper exploits a period of substantial income volatility in Russia to examine the extent to which, as well as how individuals protect their energy intakes in the face of unanticipated shocks to household income. Using rich data from the Russia Longitudinal Monitoring Survey, our results suggest that households use substitution, disproportionally cutting back spending on non-foods to protect spending on foods, change the composition of the consumption basket, and increase the consumption of 'cheaper' calories. Taken together, however, we find that total energy intakes as well as the nutritional composition of the diet are almost fully protected against income shocks. Specifically, we find that 12-16% of the effect of permanent income shocks on food expenditures is transmitted to energy intakes, with 84-88% protected through insurance mechanisms.

An analysis of the accuracy of retrospective birth location recall using sibling data.

Many surveys ask participants to retrospectively record their location of birth. This paper examines the accuracy of such data in the UK Biobank using a sample of full siblings. Comparison of reported birth locations for siblings with different age gaps allows us to estimate the probabilities of household moves and of misreported birth locations. Our first contribution is to show that there are inaccuracies in retrospective birth location data, showing a sizeable probability of misreporting, with 28% of birth coordinates, 16% of local districts and 6% of counties of birth being incorrectly reported. Our second contribution is to show that such error can lead to substantial attenuation bias when investigating the impacts of location-based exposures, especially when there is little spatial correlation and limited time variation in the exposure variable. Sibling fixed effect models are shown to be particularly vulnerable to the attenuation bias. Our third contribution is to highlight possible solutions to the attenuation bias and sensitivity analyses to the reporting error.

Do responses to news matter? Evidence from interventional cardiology.

We examine physician responses to a global information shock and how these impact their patients. We exploit international news over the safety of an innovation in healthcare, the drug-eluting stent. We use data on interventional cardiologists' use of stents to define and measure cardiologists' responsiveness to the initial positive news and link this to their patients' outcomes. We find substantial heterogeneity in responsiveness to news. Patients treated by cardiologists who respond slowly to the initial positive news have fewer adverse outcomes. This is not due to patient-physician sorting. Instead, our results suggest that the differences are partially driven by slow responders being better at deciding when (not) to use the new technology, which in turn affects their patient outcomes.

Implications of the genomic revolution for education research and policy.

Research at the intersection of social science and genomics, 'sociogenomics', is transforming our understanding of the interplay between genomics, individual outcomes and society. It has interesting and maybe unexpected implications for education research and policy. Here we review the growing sociogenomics literature and discuss its implications for educational researchers and policymakers. We cover key concepts and methods in genomic research into educational outcomes, how genomic data can be used to investigate social or environmental effects, the methodological strengths and limitations of genomic data relative to other observational social data, the role of intergenerational transmission and potential policy implications. The increasing availability of genomic data in studies can produce a wealth of new evidence for education research. This may provide opportunities for disentangling the environmental and genomic factors that influence educational outcomes and identifying potential mechanisms for intervention.

The long-term effects of early-life pollution exposure: Evidence from the London smog.

This paper uses a large UK cohort to investigate the impact of early-life pollution exposure on individuals' human capital and health outcomes in older age. We compare individuals who were exposed to the London smog in December 1952 whilst in utero or in infancy to those born after the smog and those born at the same time but in unaffected areas. We find that those exposed to the smog have substantially lower fluid intelligence and worse respiratory health, with some evidence of a reduction in years of schooling.

Rank concordance of polygenic indices.

Polygenic indices (PGIs) are increasingly used to identify individuals at risk of developing disease and are advocated as screening tools for personalized medicine and education. Here we empirically assess rank concordance between PGIs created with different construction methods and discovery samples, focusing on cardiovascular disease and educational attainment. We find Spearman rank correlations between 0.17 and 0.93 for cardiovascular disease, and 0.40 and 0.83 for educational attainment, indicating highly unstable rankings across different PGIs for the same trait. Potential consequences for personalized medicine and gene-environment (G × E) interplay are illustrated using data from the UK Biobank. Simulations show how rank discordance mainly derives from a limited discovery sample size and reveal a tight link between the explained variance of a PGI and its ranking precision. We conclude that PGI-based ranking is highly dependent on PGI choice, such that current PGIs do not have the desired precision to be used routinely for personalized intervention.

Overcoming attenuation bias in regressions using polygenic indices.

Measurement error in polygenic indices (PGIs) attenuates the estimation of their effects in regression models. We analyze and compare two approaches addressing this attenuation bias: Obviously Related Instrumental Variables (ORIV) and the PGI Repository Correction (PGI-RC). Through simulations, we show that the PGI-RC performs slightly better than ORIV, unless the prediction sample is very small (N < 1000) or when there is considerable assortative mating. Within families, ORIV is the best choice since the PGI-RC correction factor is generally not available. We verify the empirical validity of the simulations by predicting educational attainment and height in a sample of siblings from the UK Biobank. We show that applying ORIV between families increases the standardized effect of the PGI by 12% (height) and by 22% (educational attainment) compared to a meta-analysis-based PGI, yet estimates remain slightly below the PGI-RC estimates. Furthermore, within-family ORIV regression provides the tightest lower bound for the direct genetic effect, increasing the lower bound for the standardized direct genetic effect on educational attainment from 0.14 to 0.18 (+29%), and for height from 0.54 to 0.61 (+13%) compared to a meta-analysis-based PGI.

Education, Dietary Intakes and Exercise.

This paper examines the relationship between education and health behaviours, focusing on potential offsetting responses between calories in (i.e. dietary intakes) and calories out (i.e. physical activity). It exploits the 1972 British compulsory schooling law that raised the minimum school leaving age from 15 to 16 to estimate the effects of education on diet and exercise around middle age. Using a regression discontinuity design, the findings suggest that the reform led to a worsening of the quality of the diet, with increases in total calories, fats and animal proteins. However, I find that these changes are partially offset by a discontinuous increase in physical activity. Back-of-the-envelope calculations suggest little effect on the balance of calories. As such, the findings show that focusing on the two components of energy balance provides additional information that is concealed in analyses that only use a measure of obesity.

The Ultra-Processed Food Content of School Meals and Packed Lunches in the United Kingdom.

British children have the highest levels of ultra-processed food (UPF) consumption in Europe. Schools are posited as a positive setting for impacting dietary intake, but the level of UPFs consumed in schools is currently unknown. This study determined the UPF content of school food in the UK. We conducted a pooled cross-sectional analysis of primary (4-11 years, n = 1895) and secondary schoolchildren (11-18 years, n = 1408) from the UK's National Diet and Nutrition Survey (2008-2017). Multivariable quantile regression models determined the association between meal-type (school meal or packed lunch) and lunchtime UPF intake (NOVA food classification system). We showed that on average, UPF intake was high in both primary (72.6% total lunch Kcal) and secondary schoolchildren (77.8% total lunch Kcal). Higher UPF intakes were observed in packed lunch consumers, secondary schoolchildren, and those in lower income households. This study highlights the need for a renewed focus on school food. Better guidance and policies that consider levels of industrial processing in food served in schools are needed to ensure the dual benefit of encouraging school meal uptake and equitably improving children's diets.

The Impact of the Universal Infant Free School Meal Policy on Dietary Quality in English and Scottish Primary School Children: Evaluation of a Natural Experiment.

The Universal Infant Free School Meal (UIFSM) policy was introduced in September 2014 in England and January 2015 in Scotland and offered all infant schoolchildren (ages 4-7 years) a free school lunch, regardless of income. Yet, impacts of UIFSM on dietary intakes or social inequalities are not known. A difference-in-differences study using the National Diet and Nutrition Survey assessed pooled pre-UIFSM (2010-2014) and post-UIFSM (2014-2017) dietary data. English or Scottish infant schoolchildren (4-7 years; n = 458) were the intervention group, with junior schoolchildren (8-11 years; n = 401) as controls. We found that implementation of UIFSM led to an increase in infant schoolchildren having a school meal. Impacts on key food groups such as fruit and vegetables or sweetened beverages were not seen. However, there was evidence that the UIFSM policy lowered consumption of foods associated with packed lunches, such as crisps, and some nutrients, such as total fat and sodium. Policy impacts differed by income group, with larger effect sizes in low-income children. In conclusion, evaluation of UIFSM demonstrated some improvements in dietary quality but the findings suggest school meal quality needs to be improved to fully realise the benefits of UIFSM.

The impact of school exclusion zone planning guidance on the number and type of food outlets in an English local authority: A longitudinal analysis.

The use of planning policy to manage and create a healthy food environment has become a popular policy tool for local governments in England. To date there has been no evaluation of their short-term impact on the built environment. We assess if planning guidance restricting new fast food outlets within 400 m of a secondary school, influences the food environment in the local authority of Newcastle Upon Tyne, UK. We have administrative data on all food outlets in Newcastle 3 years pre-intervention 2012-2015, the intervention year 2016, and three years' post-intervention 2016-2019. We employ a difference-in-difference approach comparing postcodes within the school fast food outlet exclusion zone to those outside the fast-food exclusion zones. In the short term (3 years), planning guidance to limit the number of new fast-food outlets in a school exclusion zone did not have a statistically significant impact on the food environment when compared with a control zone.

Automatic classification of takeaway food outlet cuisine type using machine (deep) learning.

BACKGROUND AND PURPOSE: Researchers have not disaggregated neighbourhood exposure to takeaway ('fast-') food outlets by cuisine type sold, which would otherwise permit examination of differential impacts on diet, obesity and related disease. This is partly due to the substantial resource challenge of manual classification of unclassified takeaway outlets at scale. We describe the development of a new model to automatically classify takeaway food outlets, by 10 major cuisine types, based on business name alone. MATERIAL AND METHODS: We used machine (deep) learning, and specifically a Long Short Term Memory variant of a Recurrent Neural Network, to develop a predictive model trained on labelled outlets (n = 14,145), from an online takeaway food ordering platform. We validated the accuracy of predictions on unseen labelled outlets (n = 4,000) from the same source. RESULTS: Although accuracy of prediction varied by cuisine type, overall the model (or 'classifier') made a correct prediction approximately three out of four times. We demonstrated the potential of the classifier to public health researchers and for surveillance to support decision-making, through using it to characterise nearly 55,000 takeaway food outlets in England by cuisine type, for the first time. CONCLUSIONS: Although imperfect, we successfully developed a model to classify takeaway food outlets, by 10 major cuisine types, from business name alone, using innovative data science methods. We have made the model available for use elsewhere by others, including in other contexts and to characterise other types of food outlets, and for further development.

Evidence of detrimental effects of prenatal alcohol exposure on offspring birthweight and neurodevelopment from a systematic review of quasi-experimental studies.

BACKGROUND: Systematic reviews of prenatal alcohol exposure effects generally only include conventional observational studies. However, estimates from such studies are prone to confounding and other biases. OBJECTIVES: To systematically review the evidence on the effects of prenatal alcohol exposure from randomized controlled trials (RCTs) and observational designs using alternative analytical approaches to improve causal inference. SEARCH STRATEGY: Medline, Embase, Web of Science, PsychINFO from inception to 21 June 2018. Manual searches of reference lists of retrieved papers. SELECTION CRITERIA: RCTs of interventions to stop/reduce drinking in pregnancy and observational studies using alternative analytical methods (quasi-experimental studies e.g. Mendelian randomization and natural experiments, negative control comparisons) to determine the causal effects of prenatal alcohol exposure on pregnancy and longer-term offspring outcomes in human studies. DATA COLLECTION AND ANALYSIS: One reviewer extracted data and another checked extracted data. Risk of bias was assessed using customized risk of bias tools. A narrative synthesis of findings was carried out and a meta-analysis for one outcome. MAIN RESULTS: Twenty-three studies were included, representing five types of study design, including 1 RCT, 9 Mendelian randomization and 7 natural experiment studies, and reporting on over 30 outcomes. One study design-outcome combination included enough independent results to meta-analyse. Based on evidence from several studies, we found a likely causal detrimental role of prenatal alcohol exposure on cognitive outcomes, and weaker evidence for a role in low birthweight. CONCLUSION: None of the included studies was judged to be at low risk of bias in all domains, results should therefore be interpreted with caution. SYSTEMATIC REVIEW REGISTRATION: This study is registered with PROSPERO, registration number CRD42015015941.

The response to nutritional labels: Evidence from a quasi-experiment.

This paper evaluates a UK policy that aimed to improve dietary information provision by introducing nutrition labelling on retailers' store-brand products. Exploiting the differential timing of the introduction of Front-of-Pack nutrition labels as a quasi-experiment, our findings suggest that labelling led to a reduction in the quantity purchased of labelled store-brand foods, and an improvement in their nutritional composition. More specifically, we find that households reduced the total monthly calories from labelled store-brand foods by 588 kcal, saturated fats by 14 g, sugars by 7 g, and sodium by 0.8 mg.

The Use of Instrumental Variables in Peer Effects Models.

Instrumental variables are often used to identify peer effects. This paper shows that instrumenting the 'peer average outcome' with 'peer average characteristics' requires the researcher to include the instrument at the individual level as an explanatory variable. We highlight the bias that occurs when failing to do this.