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Population Health Innovation Lab (PHI-lab)

Improving health by tackling the socio-economic, environmental and system drivers of population health and health inequalities

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We are an interdisciplinary group of researchers with particular expertise in food systems, environmental factors and policy as drivers of health. We use insights from epidemiology, economics, data science and geography to understand and change the social, economic and environmental system drivers of population health. To achieve this we work collaboratively with leading researchers, policymakers and practitioners locally, nationally and internationally.


We work across two core themes:

  • Environmental and system drivers of health
  • Food systems, economics and health
About PHILAB 2 columns
About PHILAB 2 columns left paragraph

The Population Health Innovation Lab (PHI-Lab) was established in 2018. PHI-Lab is hosted within the Department of Public Health, Environments and Society at the London School of Hygiene & Tropical Medicine. PHI-Lab is dedicated to using expertise in epidemiology, economics, data science and geography to understand and change the economic and environmental system drivers of population health. In PHI-Lab we use findings from our research to test and evaluate policies and interventions that have the potential to improve health and reduce health inequalities at the population level.

We are a dynamic and social research group committed to supporting and developing the careers of talented researchers. The team currently consists of more than 15 academic staff and PhD students, making it one of the largest groups of researchers in this area in the UK. Current research is organised in two broad research themes:

  • Environmental and system drivers of health, including the role of built and natural environment on diet and physical activity; complex systems thinking and the use of agent-based models in population health; evaluation of the impact of population-level interventions on health and health inequalities
  • Food systems, economics and health, including economic drives of food choice using big data and understanding the impact of  health related food policies on diet and health

A range of funders including MRC, UKPRP, HDRUK, NIHR, BBSRC, NIA, UKRI supports our work. PHI-Lab is also affiliated with the NIHR School of Public Health Research and the Mandala Consortium.

Who we are
Team Block


Associate Professor

Laura is an Associate Professor in Public Health Economics and co-director of the PHI|Lab. She is interested in understanding linkages between public health and food systems changes, including the role of food prices as well as health-related food policies and interventions in influencing health outcomes. Laura has a MSc degree in Health Economics from University of York and a PhD degree in Economics from Trinity College Dublin. She has held two MRC Fellowships (Early Career Fellowship in Economics of Health (2014-2017) and Career Development Award (2017-2023).

Her work focuses on analysing changes in the dietary patterns in the UK in the past five years using large, disaggregated household food and beverage expenditure data and looking at whether food system changes (e.g., industry actions, regulation, policy drivers) have had an impact on what types of foods and beverages people buy and whether these could affect dietary health. Laura also has an interest in choice experiment methods for the prospective analysis of policy and intervention effects.

Google scholar

Orcid: 0000-0003-3769-8740

AT LSHTM, I am Professor Population Health, Head of the Department of Public Health, Environments & Society, Co-Director of the Population Health Innovation Lab with Dr Laura Cornelsen and Lead/PI of LSHTM's membership of the NIHR School for Public Health Research. I am also a NIHR Senior Investigator. Originally trained in Geography (BSc CGCHE), I undertook further training in Epidemiology (MSc) at LSHTM and Public Health (PhD) at the MRC Social & Public Health Sciences Unit in Glasgow. Geographical thinking still informs much of the work that I do.

My research interests include the social and environmental determinants of population health and health inequalities; evaluation of complex population health interventions, complex systems thinking, use of natural experiments in evidence-based policy, and the research-policy interface. Much of my current work is focused on food retail system transformation and population diet, particularly the impact of technology-driven changes (delivery, advertising, retail, sustainability) and the evaluation of diet-related population-level interventions. Other interests include green infrastructure and health, the environmental determinants of children’s health and the physical activity and environmental benefits of active transportation. The team is increasingly collating, linking and exploiting large-scale consumer and public secondary data, and exploring machine-learning and agent-based modelling approaches to better understand and intervene in food and transport systems. We also have extensive experience in the use of mixed-methods in evaluations of public health interventions.

You can follow me on Twitter here: @stevencjcummins

You can read a bit more about me.

Google scholar

Orcid: 0000-0002-3957-4357

Judith Eling

Judith Eling

Honorary Research Fellow

Judith is an Honorary Research Fellow at LSHTM and a Specialist Registrar in Public Health on the LKSS training scheme. Judith’s research interest is in the health and wellbeing impact of green and blue spaces. Her current work is a rapid review of impact of green space interventions for children and young people. Formerly a GP in refugee health, Judith is also qualified as a landscape architect (MLA Greenwich 2012) and starting working in Public Health in 2013, most recently at PHE’s Healthy Places Team and Surrey County Council.


Research Degree Student

Robert is a PhD candidate in Public Health. His PhD seeks to use agent-based modelling, an artificial intelligence approach, to explore how different beliefs in populations cause the convention of commuting by car, and by changing these beliefs how we may change levels of active commuting. He has a wider interest in Bayesian statistics, as well as the application of artificial intelligence techniques (including machine learning) to public health problems. He has an undergraduate degree in Computer Science (Artificial Intelligence) from King’s College London, and a master's degree in Medical Statistics from LSHTM.

Google scholar

Orcid: 0000-0003-2118-2360


Research Fellow

Suzan is a Research Fellow in Public Health. She is a mixed methods researcher, with a keen interest in qualitative research methods. Her research interests include behaviour change, implementation science, health promotion and physical and mental health comorbidities. She is currently working on the evaluation of planning policy to regulate takeaway food outlets for improved health in England in collaboration with the University of Cambridge. She is working on the qualitative components of this project, where she is exploring the implementation and acceptability of this intervention from the perspectives of local authority officials and members of the public. She is also working on producing guidance on ways to better implement the policy in collaboration with local authority officials. She completed her PhD at University College London which focused on health promotion in people with severe mental illnesses, tying together her interests and experience in both mental health and health psychology. She also holds a Masters in Psychiatric Research and a Bachelors degree in Psychology.


Research Degree Student

I am a research degree student in social epidemiology. My research uses quasi-experimental methods to investigate the impact of changes to maternity, paternity and parental leave policies on mental health and wellbeing outcomes for parents. I also work part-time in public health practice.

Google scholar

Orcid: 0000-0002-4385-9822


Research Fellow

I am a Research Fellow at LSHTM, Faculty of Public Health and Policy, department of Public Health, Environments and Society. My research interests lie in the environmental determinants of health, especially concerning dietary behaviours using epidemiological methods and spatial analysis techniques. I am an epidemiologist by training and am currently completing my PhD at LSHTM which focuses on the relationship between the neighbourhood food environment and food and drink purchasing in England, and how the COVID-19 pandemic impacted on this relationship. I hold a BSc and MSc in Health Sciences.

Orcid: 0000-0002-7388-7074


Research Degree Student

Amanda is a young researcher pursuing her PhD at the London School of Hygiene and Tropical Medicine, where she focuses on the complex relationships between food systems and health outcomes. Her work involves using systems methodologies to simulate the impact of interventions on the food environment, with critical implications for policy makers and public health practitioners. Despite her background in finance, Amanda's training in system dynamics and business administration has enabled her to tackle real-world health issues creatively. Amanda's research interest in health policy and systems research, commercial determinants of health, and use of systems thinking showcases her holistic approach to tackling complex public health issues and developing comprehensive policy solutions that account for the interconnectedness of various health determinants.

Google scholar

Orcid: 0000-0001-9447-9814


Research Assistant

Bea is a Research Assistant in the department of Public Health, Environments and Society (PHES) in the Faculty of Public Health and Policy. She recently completed a Masters in Anthropology of Food at SOAS and previously worked in an academic and pastoral support role in a London Sixth Form. She is interested in developing her qualitative research experience, particularly in youth settings, and has recently been interviewing young people about their relationships with their local food environment, with specific reference to Takeaway Exclusion Zones around their schools. As part of the ESRC-funded SALIENT project she will be conducting rapid reviews to develop an evidence base of effective interventions to encourage healthier and more sustainable food behaviours.


Research Fellow

Oana works as a Research Fellow in Public Health Economics. Oana’s background is in agricultural and food economics and her research interests lie at the nexus between food policy, health, and economics. From a methodological point of view, she uses statistical modelling techniques, experimental methods, and Big Data analysis to better understand food and health behaviours more broadly. Other skills include primary data collection, survey design & analysis and econometrical and programming skills. Her current research projects examine the impacts of calorie labelling policies on takeaway food choices and the dietary impacts of industry-led product reformulations of sugar-sweetened beverages. Past research includes examining the potential of mouse-tracking data for economic analysis, modelling the role of food supply chain initiatives in driving consumer trust and social media analyses using Twitter data. Oana holds a PhD in Agricultural and Food Economics and an MSc in Agricultural Economics from the University of Reading. Prior to her academic career, Oana worked for the World Bank, the European Commission and UK’s Department for Environment, Food and Rural Affairs (DEFRA).

Google scholar

Orcid: 0009-0009-2635-2139


Research Fellow


Research Degree Student

Toby is a PhD candidate in the department of Public Health, Environments and Society (PHES) in the Faculty of Public Health and Policy. His PhD topic is on the role of price promotions on consumer behaviour and public health. Focussing on discounts and multi-buy offers on take home purchases from food and drink retailers (such as supermarkets and convenience stores), his research looks to quantify the effect of price promotions on consumer behaviour.

Toby is also the Lead Economist for Health and Care Demand at the Health Foundation’s REAL Centre. He leads the centre’s research on multimorbidity, health and care service use and inequality. One major programme of research is a microsimulation modelling partnership with the Public Health, Policy & Systems unit at the University of Liverpool. He has completed a MSc in Economics from University College London, with distinction and a BSc in Economics from the University of Bristol.

Google scholar

Orcid: 0000-0002-0217-0228


Assistant Professor

Amy is a Research Fellow in Epidemiology and Population Health. Her main research interests are in population diet and health inequalities. She is currently working on the Mandala project, which aims to transform urban food systems to improve diet and sustainability. In her previous work at LSHTM, Amy has used household-level food and drink purchase data to evaluate changes in food and drink purchases following the introduction of advertising restrictions on products high in fat, salt and sugar on the Transport for London network and to explore associations between online delivery service use and purchasing behaviour. Amy completed her PhD at the University of Cambridge, where her work explored social inequalities in diet, focusing on food insecurity in the UK and dietary differences by ethnicity and socioeconomic position.

Google scholar

Orcid: 0000-0001-8889-523X



Honorary Assistant Professor

Nico is an Honorary Assistant Professor at LSHTM. His research interests are in the contextual and socio-environmental determinants of health, particularly diet and physical activity, and in the application of novel statistical methods. In his current project, Nico uses large disaggregated household food and beverage expenditure data to analyse the influence of policy and industry-led changes in food systems on household food and beverage consumption. He received his PhD in social epidemiology from LSHTM in 2018. Since May 2020, Nico works for the Belgian Scientific Institute of Public Health (Sciensano), where he co-leads the Nutrition and Health Unit. He is the Principal Investigator of the Belgian Food Consumption Survey.

Google scholar

Orcid: 0000-0002-4213-6040

Cherry is an Honorary Assistant Professor at LSHTM and a Lecturer in Applied Economics at University of Reading. Her research interests lie in the fields of agricultural, health and development economics. Most of her work focuses on understanding how government policies may drive changes in household food purchases and thus promote healthier diets through analysing large disaggregated purchase data and national expenditure surveys. Her current research agenda includes designing and analysing innovative policies to promote healthy and sustainable diets as well as investigating the trade-off between food and energy faced by households under difficult circumstances. She holds a PhD in Economics from University of Kent and a MSc in Applied Economics from University of Nottingham. She is also an Honorary Lecturer at the University of Exeter Medical School.

Google scholar

Orcid: 0000-0003-0686-1998


Research Degree Student

I am an AfN Registered Associate Nutritionist having obtained a BSc (Hons) in Human Nutrition at London Metropolitan University and MSc in Nutrition for Global Health at the London School of Hygiene and Tropical Medicine. I have worked in public health settings delivering weight management services as well as academic settings, conducting qualitative research. I currently work at UCL as a Research Fellow on a childhood obesity and local authority systems project. Alongside this, I am conducting my PhD, funded by the NIHR School for Public Health Research, at LSHTM. My PhD explores the impact of using emergency food parcels on household dietary practices. My interests include nutrition, qualitative research, health inequalities, food systems, social policy, food security and sociology. Orcid: 0000-0001-5517-8728

Claire Thompson

Claire Thompson

Senior Research Fellow

Claire is a Reader in Food, Inequality and Health at the University of Hertfordshire.  Her research interests focus on place-based inequalities, particularly in relation to food, health and wellbeing.  Before joining the University of Hertfordshire, Claire was based at the London School of Hygiene and Tropical Medicine working on a variety of projects including Olympic regeneration, alcohol licensing, and a Wellcome Trust Society and Ethics fellowship investigating the health and wellbeing challenges of foodbanking. She completed a PhD in Human Geography at Queen Mary University of London. Google scholar. Orcid: 0000-0002-0864-9811

Research PHILAB 2 columns
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Environmental system drivers of health


Theme: Environmental and system drivers of health

Mandala aims to transform the urban food system for population and planetary health.

The food system is not currently conducive to supporting population or planetary health. Poor diet and related diseases are a major burden on population health and healthcare resources, whilst food production practices and food waste have consequences for the sustainability of diets and for the environment. Poor diet is also strongly socioeconomically patterned and many households in the UK struggle to afford sufficient nutritious food, making this an important health inequalities issue.

The COVID-19 pandemic has highlighted the fragility of urban food systems and exacerbated food insecurity and existing dietary inequalities. Changes to the food system need to be made in order to make it healthier, more sustainable and more equitable while preserving economic viability. Changes that improve population and planetary health could be well-aligned as healthier foods such as wholegrains, fruits, vegetables, nuts and seeds have lower environmental impacts than less healthy foods, such as red and processed meats.

The Mandala project aims to use Birmingham, a large and diverse English city, as a case study to identify leverage points within the food system with the greatest potential to improve population and planetary health. This project is led by Prof Martin White, Professor of Population Health Research at the University of Cambridge, and brings together an interdisciplinary team of researchers from the Universities of Cambridge, Birmingham, Warwick, Exeter, Liverpool, UCL and LSHTM. As part of this large consortium, LSHTM will lead on curating data resources to inform and facilitate food system transformation, evaluations and modelling studies.

Funder: UK Research and Innovation (UKRI) Strategic Priorities Fund (SPF) as part of the Transforming the UK Food System for Healthy People and a Healthy Environment programme.

Dates: Mar 2021- Mar 2026

Team members: Amy Yau, Steven Cummins


Mandala logo
The impact of ‘emergency’ food parcels on the dietary practices of low-income households in the South of England: A multi-method qualitative study (PhD)


  • Environmental and system drivers of health
  • Food systems, economics and health
  • Social policy and health

This research project aims to explore the extent to which food bank practices intersect with household dietary practices in Portsmouth and the London Borough of Brent.

Food insecurity in the UK has become a public health emergency. This has led to an increase in the use and demand of emergency food aid, commonly in form of food banks. Currently over 2,000 food banks are estimated to operate in an official capacity in the UK. Although emerging, little is known on the use of food banks at a household level and the extent to which food banks consider dietary needs and preferences. Those who use food banks have limited choice as the food available is pre-determined by donations, which has the potential to increase their nutritional vulnerability. The overall aim of this thesis was to therefore determine the extent to which food banks meet household dietary needs and preferences by exploring the intersection between emergency food parcels and household dietary practices. This project utilises a multi-method qualitative approach. Firstly, a critical discourse analysis of twelve government and third-sector publications from 2013 was conducted to determine how the role of food banks have been framed in the discourses of food poverty and hunger. Secondly, an ethnographic study of food banks in Portsmouth and the London Borough of Brent was conducted. Remote and in-person interviews were conducted with a sample of 47 participants including food bank staff and volunteers (n = 23), long-term food bank users (n = 21) and public health practitioners (n = 3). These were supplemented by participant observations in seven food banks.

Team members:

  • Denise Ndlovu
  • Steven Cummins
  • Claire Thompson

Twitter: @NdlovuDenise

The impact of ‘emergency’ food parcels on the dietary practices of low-income households in the South of England

Food purchasing, food environments and the COVID-19 pandemic in England: Exploration of associations using large-scale secondary data (PhD)

Theme: Environmental and system drivers of health

This project explores how the neighbourhood food environment influences household food and drink purchasing in England, and how this relationship changes during the COVID-19 pandemic.

The neighbourhood food environment comprises the food retail, e.g. supermarkets, corner shops, restaurants and takeaways outlets, around the home. Inequalities in the neighbourhood food environment are thought to relate to inequalities in dietary behaviours and health. However, the evidence on the relationship between the food environment and individual dietary health outcomes in the UK is inconclusive, which may be due to the great variety of methodological approaches in the field, including poor quality nutritional outcome data. Moreover, there is a lack of evidence on how this relationship changed during the COVID-19 pandemic, which restricted both individual movement and food retail. The present project addresses these knowledge gaps through a quantitative lens. Its aim is to explore the relationship between exposure to the local food environment and household food and drink purchasing in England, and how this relationship changed during the COVID-19 pandemic. It does so by pursuing the following 4 objectives:

  1. To ascertain changes in food and drink purchasing patterns during the COVID-19 pandemic, and whether they varied with region, sociodemographic characteristics, and usual purchasing
  2. To explore associations between the neighbourhood food environment and purchases before the COVID-19 pandemic, and whether they varied by region
  3. To explore associations between the neighbourhood food environment and purchases during the COVID-19 pandemic and compare them to the non-pandemic period, and examine whether observed effects vary with region
  4. To explore associations between area deprivation and exposure to online food delivery services during the COVID-19 pandemic and whether this varied by region

In doing so, the project utilises large-scale food and drink consumer purchasing data which were available for London and the North of England between January 2019 and June 2020, which are analysed using chiefly spatial and epidemiological methods.

In brief, the project finds that on a population level, there is no consistent association between exposure to the neighbourhood food environment and household food and drink purchasing. However, there is geographical variation, indicating that neighbourhood measures matter more for some people in some places. During the first national lockdown, there was also no evidence of a relationship between the neighbourhood food environment and household food and drink purchasing, and no geographical heterogeneity was found. In its final objective, the project established that digital food environment changed considerably during the first year of the COVID-19 pandemic, in that exposure to online food delivery increased by an average of 132% between April 2020 and May 2021. Exposure to online food delivery services was patterned across area deprivation, with the relationship depending on the geographical context, but existing inequalities did not widen during the first year of the pandemic.

This PhD project is funded by the Bloomsbury Colleges and supervised by Prof Steven Cummins and Dr Laura Cornelsen, both PHI|lab members, and Dr Andrea Ballatore at King’s College London. It started in September 2019 and is expected to be submitted in April 2023.

Team members:

Alexandra Kalbus, supervised by Steven Cummins and Laura Cornelsen

Simulating the effect of urban food system interventions on dietary behaviour: a qualitative system dynamics and spatial agent-based modelling approach (PhD)

Theme: Food systems, economics and health

Examine interventions to reduce exposure to food retail environments and decrease out-of-home consumption of high-fat, high-salt, or high-sugar (HFSS) foods through simulation.

Obesity is a complex public health issue, and studying the impact of exposure to the food retail environment is crucial in understanding the drivers of poor dietary habits and developing effective interventions. The local retail environment, including restaurants, convenience stores, and fast-food outlets are known to offer high-calorie, low-nutrient meals at low prices, while frequent out-of-home eating has been associated with poorer nutrient intake.

The overconsumption of energy-dense and nutrient-poor food, particularly from fast food outlets, contributes significantly to weight gain. The increasing consumption of food outside the home, coupled with the availability of low-cost unhealthy food, is a major factor driving the obesity pandemic. In the UK, two-thirds of adults are overweight or obese, and the trend towards eating out is growing.

The complexity of the obesity epidemic requires a deeper understanding of the factors that drive unhealthy eating habits, as traditional statistical models often struggle to incorporate intricate dynamics. Systems science methods, such as agent-based modelling and system dynamics modelling, are considered promising tools for investigating these intricate processes.

To better understand how individual interaction with the food retail system produces unequal patterns of consumption in the population, this study uses systems dynamics and agent-based modelling, with a focus on reducing consumption of high-fat, high-salt, or high-sugar (HFSS) food consumed out of home.

This study aims to accomplish three goals. Firstly, to understand the mechanisms involved in the food retail system by creating a Causal Loop Diagram (CLD). The CLD will help identify the system drivers that influence the decision to purchase HFSS food. Secondly, to develop a spatial agent-based model that simulates how individuals interact with their environment and how this affects their consumption of HFSS food. The model will identify the factors that are most effective in reducing inequalities in exposure to the food retail environment. Thirdly, using the developed ABM, the thesis will simulate the impact of up to three policies aimed at modifying these identified targets for intervention to explore if they influence the food retail environment and out of home food consumption.

This study was supported by the National Institute for Health Research (NIHR) School for Public Health Research (SPHR), Grant Reference Number PD-SPH-2015.

Team members: Amanda Karapici, Steven Cummins 

Twitter: @amik89

How do beliefs influence the decision to undertake active travel in complex social networks: an agent-based modelling approach (PhD)

Theme: Environmental and system drivers of health

This project uses agent-based modelling, an artificial intelligence approach, to explore how individuals make their decision about how to commute based upon what they believe.

Active travel, which is travel by more active modes, such as walking and cycling as opposed to driving, reduces the risk of a wide range of diseases, including obesity and cancer, as well as improving mental health. It also has benefits for climate change and air pollution. However, how we best intervene to increase levels of active travel is unknown, and the evidence is mixed. This may be because our ‘transport-relevant beliefs’ – which influence, but may not directly be about, transport behaviour – both cause transport behaviour and arise by observing the behaviours of others. This results in a complex spread of beliefs and behaviour around social networks; those not directly to interventions may still change their behaviour because of observing behaviour and adopting beliefs from those who were exposed to the intervention. A better understanding of the role beliefs plays in transport behaviour, the role transport behaviour plays in informing our beliefs, and the spread of beliefs around social networks may help us design more effective interventions.

The belief–desire–intention (BDI) model of an individual’s decision to perform behaviour, states that an individual’s beliefs impact their desires – behaviours an individual would like to perform. The individual then chooses between their desires to obtain intentions – behaviours an individual is actively planning to perform. If we wish to change our behaviour, which, according to the BDI model, stems from our intentions, we must target policies and interventions earlier in the chain, by targeting beliefs.

The aims of the project are: (i) to understand how transport-relevant beliefs influence travel behaviour; (ii) to assess whether active travel influences the spread of transport-relevant beliefs and how this spread affects the success of interventions seeking to increase active travel; and (iii) to investigate whether active travel interventions can be designed in a way that exploits the spread of transport-relevant beliefs around a social network. To achieve this, this project will: build upon existing models of beliefs to develop a mathematical model for belief–behaviour interaction which considers the spread of beliefs; conduct a systematic review to understand how beliefs impact travel behaviour; design and implement an agent-based simulation platform and use this to investigate a range of active travel interventions.

An agent-based simulation platform is a model-based artificial intelligence approach to modelling a complex system where agents, in this case individuals, are given simple rules for how they interact with one-another and with the environment. For example, if I believe that cycling is good for the planet, then I will be more likely to cycle. Through these simple rules, emergent behaviour may occur. This is behaviour which was not anticipated and arises due to the combination of simple rules.

This PhD studentship is funded by the Medical Research Council (as part of the MRC-LID scheme), from September 2020 to December 2023.

Team members: Robert Greener, supervised by Steven Cummins

Twitter: 0x_r0bert

Evaluating the effects of maternity, paternity and parental leave policy changes on parental mental health using quasi-experimental methods (PhD)

Theme: Environmental and system drivers of health

This project will look into the effects of a series of UK policy reforms to maternity, paternity and parental leave on the mental health of parents.

Early parenthood might be an important time for future mental health and wellbeing. New parents can lose sleep and have demands on their time, money and emotional resources. Social policies supporting paid maternity, paternity or parental leave might influence the mental health of parents in the short term by supporting them at this time, and in the long term by affecting their future working life.

Leave policies vary around the world, with different lengths of leave, levels of payment and amounts of time allocated to mothers and fathers. Although there is growing evidence that taking maternity leave is linked to maternal mental health, it is unknown what leave policies would lead to the best outcomes.

The UK is an interesting case study. It has unusual maternity and paternity leave policies, with a comparatively short period of statutory entitlement to high-rate maternity pay, and limited leave rights reserved for fathers.

This project will investigate what happened to mental health for parents after three different changes to their leave rights.

Funder: MRC-LID

Team members: Emily Humphreys

Start date: September 2021

SALIENT: food System triALs for Impact on Environment, Nutrition and healTh


  • Environmental and system drivers of health
  • Food systems, economics and health
  • Social policy and health

The SALIENT project aims to design and trial 10 innovative food system interventions within England to improve public and planetary health.  

Unhealthy, less sustainable foods that are cheaper to produce and consume are contributing to some of the biggest challenges for public health and the environment facing society today. In response to the urgent need for healthier and more sustainable food systems, the SALIENT project aims to take an ambitious and innovative approach to designing and trialling 10 food system interventions. Working across 10 institutions, the SALIENT team consists of over 20 interdisciplinary experts specialising in behavioural science, public health, systems and environmental science and health economics. The project has been funded by the UKRI Economic, Social and Research Council (ESRC) and will be co-led by experts in food systems research Professor Martin White and Professor Peter Scarborough.

In the first phase of the project (January-May 2023), we will identify which interventions to study in phase two. Alongside working with two public panels and policymakers from relevant government departments, researchers in PHI|Lab will conduct a review of the evidence to develop a list of possible interventions. Our analysis will inform meetings with potential food system partners, which consist of both large and small organisations working in the retail, catering and community support sectors. To transition into the delivery phase, the team will decide which interventions are likely to have the best chance of having large, equitable, and long-term effects on healthy, sustainable food purchasing.

If our application is approved, in the second phase (June 2023 - March 2025) we will deliver these interventions in real-life food purchasing settings to try and understand what works best and why. Our interventions will focus on five mechanisms that have been shown to affect behaviour: availability, size, promotions, price and provision of information. We will prioritise interventions that are equitable, effective and scalable, whilst recognising that they must also be deliverable and cost-effective for partners.

Team members: Professor Steven Cummins, Dr Laura Cornelsen, Dr Claire Thompson, Bea Savory

Food system trials to encourage healthy, sustainable diets

Associations between residential greenspace exposure and premature mortality in London, UK: a data-linkage study

Theme: Environmental and system drivers of health

Does access to greenspace influence mortality in London?

This project had a focus on creating population-wide spatially referenced environmental exposure data linked to large-scale secondary data resources. The aim was to unpick causal associations between environmental exposures and clinical endpoints and assess effects on health inequalities of environmental exposures using exposure to greenspace as a case-study.

Urban greenspaces might reduce non-communicable disease risk but the links between greenspaces and mortality related to non-communicable disease remain unclear. In this project we estimated the associations between residential greenspace quantity and access with all-cause, cardiovascular disease, cancer, respiratory, and type 2 diabetes mortality.

We linked 2011 UK Census data of London-dwelling adults (to data from the UK death registry and the Greenspace Information for Greater London resource (N=4 645 581). We calculated percent greenspace area, access point density (access points per km2), and distance (metres) to the nearest access point for each respondent's residential neighbourhood (defined as 1000-m street network buffers) for greenspaces overall and by park type using a geographic information system. We then estimated associations using Cox proportional hazards models, adjusted for a range of confounders. 

Funder: Health Data Research UK

Duration: Sept 20 - June 22

Team members: Professor Steven Cummins, Dr Samantha Hajna (now at Brock University) and Dr Vahe Nafilyian (now at ONS)

Kids’ Environment and Health Cohort (KiTE)


  • Environmental and system drivers of health
  • Social policy and health

Developing a large-scale e-resource to explore the impact of the environment on child health, wellbeing and development.

Children are much more vulnerable to health-damaging features of the environment in and around their homes and schools than adults. This can include air pollution, overcrowding, fast food advertising near schools, and lack of access to greenspaces. Children who are exposed to these environmental factors are at greater risk of developing long-term conditions such as asthma or mental health problems, and not doing so well in school.

The government is introducing policies to improve local environments and housing, partly to slow and mitigate the effects of climate change. Several changes are also taking place in the social environment around where children live and go to school, due to austerity policies and the Covid-19 pandemic, including closure of libraries, childcare providers and high street shops.

In this project, we will set up a new national data resource that will allow researchers to examine how the local physical and social environment influences children’s health and schooling across England.

The Kids’ Environment and Health Cohort project is led by University College London, in collaboration with London School of Hygiene and Tropical Medicine, and City, University of London, in partnership with the Office for National Statistics (ONS), working with NHS Digital and the Department for Education.

This project will set up a national database containing de-identified data from schools, hospitals and community pharmacies, on health and education histories for all children born in England from 2006 onwards - around 11 million children. This data will be linked to information about their mothers’ health during pregnancy as well as data on local environments in and around children’s homes and schools. The data will be linked under approvals from the Confidentiality Advisory Group, the ONS, NHS Digital and the Department for Education.

Funder: ADR-UK via ESRC.

Dates: December 2022 – December 2025

Team members: Professor Steven Cummins, Dr Emilie Courtin and Dr Samantha Hajna (now at Brock)

Kids’ Environment and Health Cohort

ADRUK Kids’ Environment and Health Cohort

Evaluation of planning policy to regulate takeaway food outlets for improved health in England


  • Environmental and system drivers of health
  • Food systems, economics and health
  • Social policy and health

The impact planning policy to reduce the proliferation of fast-food in England.

Poor diet and obesity are leading causes of mortality. Takeaway food outlets (‘takeaways’) sell energy dense food, with frequent consumption linked to weight gain. There are 60,000 takeaways in England with more in deprived areas and annual growth four times that of population growth. Physical access (‘exposure’) to takeaways is associated with takeaway consumption and obesity.

Urban planners are unable to remove planning permission from existing takeaways, but they can refuse permission to new takeaways. The most common form of planning policy is the school-based ‘exclusion zone’ adopted by 44 of 325 LAs in England to date. The intent of this intervention is to prevent further takeaway proliferation around schools by denying new takeaway planning applications. While appearing to target children, our previous findings suggest this is a politically acceptable means to reduce whole population takeaway exposure. The health and other impacts of exclusion zones are unknown.

The aim of our study is to assess what the impact of exclusion zones on the number of takeaways is. Using a dataset of all food outlets in England, we will compare takeaway numbers in areas with and without exclusion zones, two years before and after zones are introduced. We will also study areas just outside zones in case takeaways are displaced there. Any health impacts of zones are likely to be small and take a long time to occur. We will use statistical modelling to estimate the impact of zones on obesity and health.

We are also exploring how planners and those in public health practice have implemented the policy and will produce a toolkit to other local councils implement the policy in their area. In addition, we will conduct research with young people to explore how they feel about these kinds of policies in their neighbourhoods and how they use their local food environment to buy and consume takeaway food.

This project is led by Dr Tom Burgoine at the MRC Epidemiology Unit, University of Cambridge.

Funder: NIHR

Dates: April 2021 – March 2024

Team members: Professor Steven Cummins, Dr Suzan Hassan, Bea Savory

Evaluation of planning policy to regulate takeaway food outlets in England

Food systems, economics and health

Impact of calorie labelling on online takeaway food choices: an online menu-based choice experiment in England

Theme: Food systems, economics and health

This project examines whether providing calorie information on online takeaway food menus leads to healthier food choices.

The out-of-home food choices that people make can have a direct impact on their health. Eating out-of-home is linked to higher energy intake and higher body weight, which are key risk factors for obesity and diabetes. In the UK, most main meals served in major restaurant and fast-food chains contain more than 600 kcal—the recommended energy content for a main meal. Additionally, one in four starters and one in five desserts in UK chain restaurants exceed the recommended energy intake for an entire meal.

In April 2022 England introduced Calorie Labelling Regulations for Out of Home Food (OOHF) Sector. This requires large businesses (defined as those with 250 or more employees) selling food in scope of the Regulations to display the energy content of the food in kilocalories (kcal), reference the size of the portion to which the calorie information relates and display the statement that ‘adults need around 2000 kcal a day’. The requirement extends to food that is sold on a website or mobile application, including third party delivery apps. Existing research has shown that providing calorie content of individual food items does not appear to have much of an effect in reducing calorie consumption. However, some evidence shows that providing information on the total amount of calories (nutrients) might lead to a greater effect.

This study aims to examine whether a policy that provides information on the total amount of calories ordered in an online setting leads to healthier food choices compared to a policy that provides calorie information for individual items only. To achieve this objective, an online Menu-based Choice Experiment (MBCE) will be conducted to model consumers’ responses to calorie labelling on online takeaway food menus. The design will also allow to examine whether either type of information on calories leads to healthier food choices compared to no information. This study has therefore direct relevance to the recently introduced regulations in England but goes a step further to examine whether provision of information regarding total calories ordered in addition to calories for individual items will impact food choices made in an online setting.

The MBCE was conducted as an online survey in November 2022 among a randomly selected sample of individuals in England (n=1,000) who were recruited from a large nationally representative panel. Primary interest for this study is the estimated likelihood of choosing healthier items from a menu consisting of one healthy and two less healthy meal food/drink items. Furthermore, we asked the respondents about their knowledge and perception of calorie labelling and factors they consider important when making food choices. Findings from this study will enhance the existing evidence base on the effectiveness of provision of calorie information in encouraging healthier out-of-home food choices with the potential of informing policy designs and thus improving health outcomes.

This project is funded by the Medical Research Council.

Start date: 1 July 2022

Contact person: Oana Tanasache (

Team members: 

  • Laura Cornelsen
  • Oana Tănăsache
  • Cherry Law
  • Steven Cummins
Does product reformulation of sugar-sweetened beverages lead to healthier diets?

Theme: Food systems, economics, and health

This project examines whether industry-driven sugar reformulation initiatives lead to healthier diets.

Obesity has become a major global challenge. With the number of obese adults nearly tripling over the past forty years, obesity is now affecting more than 1.9 billion adults globally. Obesity is not only is a key risk factor for several non-communicable diseases, such as cardiovascular disease, some forms of cancer and diabetes. Aligned to these global trends, U.K. is severely affected by the prevalence of obesity. More than one in four people was obese in 2015 with obesity rates expected to affect 35% of the population by 2030. Obesity is not only affecting adults, but also children with a large share of children in England reported as obese or overweight.

Unhealthy dietary patterns are reported to be a key contributor to obesity rates. Excessive consumption of sugar-sweetened beverages (SSBs) is believed to contribute to these unhealthy diets especially among children. Several initiatives have been put forward in recent years to reduce consumption of these drinks. One of these initiatives is product reformulations of SSBs which involve a reduction in the added sugar content of these drinks (usually through sugar substitutes).

This project examines whether reformulation of sugary drinks usually consumed by children has a positive impact on diets. We do this by using a large representative dataset of British household food purchases over the 2012-2017 period and investigate whether reformulation of SSBs lead to healthier food baskets containing less calories and sugar.

Findings from this project will improve our current understanding of product reformulation as a tool for improving diets. These findings will also inform future policy initiatives in relation to health-related food policies.

Contact person: Oana Tănăsache (

Team members:

  • Laura Cornelsen
  • Oana Tănăsache
Do healthy diets cost more?

Theme: Food systems, economics and health

This project examines whether healthier food baskets purchased by British households are more expensive than less healthy food baskets.

Healthy foods are widely reported to be more costly than unhealthy foods. This is often reported as one of the key barriers to a healthy and nutritious diet. The recently published UK National Food Strategy shows that highly processed foods, that tend to be unhealthy, are on average three times cheaper per calorie than healthier foods. However, price per calorie is not ideal for assessing the relative cost of healthy and unhealthy foods as healthier foods are typically lower in fat, sugar and refined carbohydrates and thus have fewer calories. A more appropriate alternative would be to look at the differences in the cost of food baskets between those consisting mainly of healthy foods and those containing predominantly less healthy foods.

This project will explore the association between the healthiness and cost of food baskets, using a large representative British household purchase panel of foods and beverages bought to consume at home in 2017. We will apply the Nutrient Profiling Model to classify food and drink items purchased that are high in fat, sugar and salt (HFSS) and use the share of calories obtained from HFSS to measure the healthiness of the diet. By examining within-household variations in 4-weekly food baskets over the data period, we will assess how the share of HFSS energy is associated with the per person food spending on the baskets. We will also examine if this association differs across socioeconomic groups to gain insights on any diet-related inequality.

Findings from this project will improve our understanding of the complexity of food choices and verify the commonly held view that healthier food baskets are more expensive than the less healthy ones. These findings will help policymakers in designing food policies to improve diet-related health.

Contact person: Cherry Law (

Team members:

  • Laura Cornelsen
  • Cherry Law
  • Richard Smith
CO-designing for healthy People and Planet: food system Economic Research (COPPER)

Theme: Food systems, economics and health

COPPER project will work with the public and policymakers to design food subsidy and tax scenarios to estimate their impact on health, health inequalities, household economics, macroeconomics and the environment.  

The food that we eat in the UK impacts on our health and our wallets, with particularly large impacts for the poorer in our society. It also impacts on planetary health and the UK economy. One option to address these challenges is to introduce food taxes and subsidies to incentivise healthy, sustainable food and support low-income groups. But taxes and subsidies are politically difficult to introduce due to concerns over individual agency and stigmatisation. For such policies to be successful, it is vital that they are co-designed with the public and policymakers and their potential impact across multiple outcomes is established. The aims of the COPPER project are to a) co-design tax and subsidy scenarios with public and policymakers, b) develop a research infrastructure of linked datasets and integrated health, economic and environmental impact models, c) estimate the impact of six policy scenarios and communicate our results with public and policymakers.

The team at LSHTM will use household food purchasing data linked with environmental outcome measures to fit a consumer demand model. We will estimate food demand sensitivity to changes in prices which will feed into evaluation of the impact of the scenarios on nutritional quality, price of the diet and environmental outcomes for different income groups. In addition, LSHTM team will estimate how the tax and subsidy scenarios change GDP, jobs in the food industry and tax revenue using a computable general equilibrium macroeconomic model.

Team members: Laura Cornelsen (PHI-Lab, GHECO), Marcus Keogh-Brown (GHECO), Henning Tarp-Jensen (GHECO)

Partners: University of Oxford (lead); University of Exeter; University of Reading; Food Foundation


Funder: NIHR

Start date: May 2022

Vulnerability of the UK food system to climate change: exploration of indicators, impacts and policy responses

Theme: Food systems, economics and health

This PhD examines the vulnerability of the UK food system to climate change and explores how the UK measures and responds to these impacts.

Climate change will increasingly impact global food systems which has potential consequences for food security and diet quality. The Intergovernmental Panel on Climate Change (IPCC) reports of “irreversible damage to global food security as many natural and human systems are unable to adapt to climatic changes and further increase in global warming (between 1-2˚C) would contribute additional pressure to food production and access”. This can lead to many forms of malnutrition in vulnerable populations. Non-resilient and vulnerable food systems can be challenged by climate change through direct impacts on crop yields affecting food production, nutrient composition and bioavailability as well as influencing access to and affordability of food. The UK has a highly complex food system with long supply chains, and is dependent on imports often from highly climate-vulnerable countries as well as experiencing its own environmental challenges. Therefore, it is critical that climate change impacts and policy responses are understood to identify potential vulnerabilities and subsequent consequences for food and nutrition security.

Advances in agricultural production and significant transitions in global food demand, have shifted disease profiles such that food-related non-communicable diseases rather than undernutrition are now the largest contributor to the global burden of disease. However, inequalities in the distribution of food supply for adequate and healthy diets remain. Food insecurity is a known risk factor for many nutritional health outcomes such as diabetes, hypertension, overweight and obesity and poor mental health which can be exacerbated by economic, social and environmental shocks. The UK Food Security Report states that 2.2 million UK households regarded themselves as food insecure in 2019/20. Only 0.1% of the population currently meets all UK dietary guidelines, and micronutrient rich, high fibre foods such as fruits, vegetables and legumes are particularly under-consumed. Climate change poses an additional future risk to the UK’s food supply and food security as discussed above.

This PhD aims to examine the vulnerability of the UK food system to climate change and explore how the UK measures and responds to these impacts. Firstly, I will conduct a scoping review mapping climate-related food-system indicators used to monitor climate change impacts and compare this to how the UK currently monitors these impacts. I will then identify implemented actions to respond to climate impacts on food systems through a policy review of national and regional food strategies and national climate risk assessments across UK and Europe. Next, I will assess the impact of past extreme weather events on the UK food system by examining changes in food prices and consumer purchasing through a time series analysis of consumer food purchase data. Finally, I will explore policy responses to climate impacts in the UK food system and identify policy gaps, implementation barriers and facilitators for effective decision-making. This will be through a qualitative analysis of semi-structured stakeholder interviews. The studies conducted will inform a range of stakeholders by providing evidence-based recommendations to ensure the resilience of the UK food system.  

This PhD is affiliated with the NIHR Health Protection Research Unit in Environmental Change and Health led by LSHTM with the UK Health Security Agency, Met Office and University College London.

Contact person: Grace Turner (

Team members: 

  • Grace Turner
  • Laura Cornelsen
  • Cherry Law
The impact of price promotions on consumer behaviour and public health (PhD)

Theme: Food systems, economics and health

Price promotions form an important part of food and beverage marketing in the UK. This research seeks to measure the impact of these promotions on the choices people make while buying food and to what extent our diets are affected by them.

Increasing prevalence of overweight and obese people in England has led policymakers to consider regulating the use of price promotions on foods high in fat, sugar and salt content.

In Britain, price promotions are used as a key part of the marketing and competition strategy in national supermarket chains, as well as independent stores. Price promotions involve discounting prices at the point of sale and are available to all customers. They consist of total price reductions (TPRs), in which the good is offered at a price below recommended retail price, often presented as a percentage discount off the price or volume-based discounts (multi-buys), in which an additional percentage or whole units are offered upon purchase of a specified amount (e.g., buy-one-get-one-free deal, or 30% extra free). Both types of promotion are often indicated by brightly coloured, large stickers which describe the terms of the price reduction.

This study focusses on the analysis of Kantar GB Fast Moving Consumer Goods (FMCG) panel, a data set recording the shopping behaviour of over 30,000 households in Britain. It uses micro-econometric techniques to estimate the extent to which this promotion based marketing disrupts the content of people’s shopping baskets.

In January 2019 the Government opened a consultation programme for a policy proposal which significantly restricts the use of price promotions that can induce consumers to buy higher volumes of unhealthy foods and beverages. These proposed policies are the first of their kind in public health and are believed to reduce excess purchasing, and therefore over-consumption of unhealthy products. While the impact of price promotions on sales has been of interest to marketing academics for a long time with modelling studies showing its use increases food and drink sales by 12-43%, it is only now being picked up in the public health sphere. However, the existing evidence rarely considers the “overall” impact of price promotions as a strategy, more often focussing on the sale of individual brands and products.

With the government’s policy proposed, but delayed and not yet enacted, this analysis is making a timely contribution to public debate.

Publications include:

Reducing consumption of unhealthy foods and beverages through banning price promotions: what is the evidence and will it work?

The impact of price promotions on sales of unhealthy food and drink products in British retail stores

Team members: Toby Watt, supervised by Laura Cornelsen, Walter Beckert (BBK) & Richard Smith (Exeter)


Publications (Feed)
Scott, LJ; Toumpakari, Z; Nobles, J; Sillero-Rejon, C; Jago, R; CUMMINS, S; Blake, S; Horwood, J; Vocht, FD;
BMC public health, (2023).23 1 10.1186/s12889-023-15567-1.
Rogers, NT; Pell, D; Penney, TL; Mytton, O; Briggs, A; CUMMINS, S; Rayner, M; Rutter, H; Scarborough, P; Sharp, SJ; Smith, RD; White, M; Adams, J;
PLoS medicine, (2023).20 3 10.1371/journal.pmed.1004201.
Penney, TL; Jones, CP; Pell, D; CUMMINS, S; Adams, J; Forde, H; Mytton, O; Rutter, H; Smith, R; White, M;
BMC public health, (2023).23 1 10.1186/s12889-023-15190-0.
McKevitt, S; White, M; PETTICREW, M; Summerbell, C; Vasiljevic, M; Boyland, E; CUMMINS, S; Laverty, AA; Junghans, C; Millett, C; De Vocht, F; Hrobonova, E; Vamos, EP;
BMJ global health, (2023).8 1 10.1136/bmjgh-2022-010216.
Petersen, J; Alexiou, A; Brewerton, D; CORNELSEN, L; COURTIN, E; CUMMINS, S; MARKS, D; SEGUIN, M; Stewart, J; Thompson, K; EGAN, M;
BMJ open, (2022).12 12 10.1136/bmjopen-2022-065747.
Colasanti, R; MacLachlan, A; Silverman, E; McCann, M; Mitchell, R; Hunter, R; CUMMINS, S; Moore, L;
Lancet (London, England), (2022).400 Suppl 1, 10.1016/s0140-6736(22)02243-7.
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Phi-Lab has expertise in quantitative and qualitative methods including; GIS, multi-level modelling, interrupted-times series, econometrics, public health evaluation (inc natural experiments and quasi-experiments), agent-based modelling, data science, interviewing, focus-groups and ethnography.

Fellowships / Visiting Fellowships

We have an excellent track record of supporting applications for external junior and senior research fellowships. We have sponsored and hosted many successful applications to funders such as MRCCIHRNIHR, ERC and Wellcome Trust.

We can also help support external faculty and researchers who wish to take research leave or a sabbatical at PHI-Lab through providing letters of support and desk space.

If you would like to discuss a potential application and how we can support please contact us.

Doctoral Studentships

If you would like to discuss a potential PhD project with PHI|Lab members please contact us via email and we can discuss your application and see if we are able to supervise your project. General information on applying for a PhD at LSHTM can be found on the MPhil and PhD - Research Degrees course page.

Our team members regularly propose topics for MSc summer projects and provide supervision. These topics are generally circulated by MSc course coordinators but if you have an idea for summer project that falls under the PHI-Lab themes do get in touch with us.

Examples of projects supervised:

  • Associations between park proximity and childhood weight status: A case study in the London Borough of Lambeth
  • Are national and international nutrition recommendations effective at improving diets? A panel interrupted time-series analysis of household food and beverage purchases in Britain
  • Do households in Great Britain that buy more unhealthy food spend more money? Analysis of household-level purchases from a nationally representative panel
  • Change in alcoholic beverage sales following a 10-pence levy on sugar-sweetened beverages in a chain of national restaurants in the UK
  • Understanding the patterns of organic food and beverage purchases in Great Britain
  • Investigation into physical activity and sedentary times association with later mental health outcomes in East London adolescents
  • Implementing nutritional practices into UK food banks: A qualitative study exploring stakeholders involved in improving the nutritional quality of food parcels
  • Analysis of purchasing patterns of beverages and socio-demographic profile of purchasers, using latent class analysis
  • Intra-household consumption of non-alcoholic beverages – a secondary data analysis of British households
  • Improving adherence to UK guidelines on the early introduction of allergenic foods in infancy to prevent food allergies: the applicability of behavioural economics
  • Exploring the price effect of food subsidies on purchase and consumption of healthy foods
  • Taxing sugar sweetened beverages in Mexico: evidence of policy effectiveness and consumer attitudes