Use of IoT to tackle childhood obesity


< Project overview >

Research shows that maintaining a healthy weight in childhood can avoid obesity in later life. Increasing activity and general fitness, improving mental health and promoting a healthy diet are all key areas to address in order to reduce future healthcare burdens. The UK wide costs attributable to people being obese or overweight are projected to reach £9.7 billion per year by 2050 (source:

In this project, partners from the University of Oxford, Oxford Brookes University and the Oxfordshire County Council came together to explore opportunities to identify and draw together IoT-enabled solutions to positively impact this at scale.

Project aims

The UK wide costs attributable to people being obese or overweight are projected to reach £9.7 billion per year by 2050. Preventing even a 1% increase in the prevalence of people who are overweight and obese could lead to combined savings of around £97 million per year for the NHS and local authorities, in addition to the improved health of the individuals and communities affected (source:

In Oxfordshire, 30% of children aged 10–11 years and 20% of children aged 4–5 years were either overweight or obese in 2016–17. Reducing obesity in Oxfordshire’s children is a priority issue for our principal beneficiaries (ie Oxfordshire’s children) and Oxfordshire County Council’s Health Improvement Board agreed the reduction of obesity as a priority in spring 2018, endorsing a plan to develop a more comprehensive adoption of a whole systems approach from April 2019.

By working with partners and utilising existing programmes, our project aimed to facilitate these processes by:

  • Identifying IoT-enabled solutions (eg activity trackers) that can be used to positively impact children/youth health.

  • Exploring existing national and international activities that may inform this work and future scale up of the programme.

  • Identifying ethical and regulatory barriers to the use of IoT in this setting.

Through our project we anticipated to address the following knowledge exchange barriers:

  • Educational barriers: lack of familiarity with the technology on the part of the schools and children, and with the domain on the part of the technology providers.

  • Connectivity barriers: lack of knowledge of various stakeholder skills and interests.

These barriers are of obvious importance because failure to address them would mean that we would not be able to engage with our principal beneficiaries in a meaningful way to facilitate behaviour change supporting the adoption of healthier behaviours.

What was done

To explore our three project aims we initiated three parallel workstreams.

1. A systematic review of the literature to explore the use of IoT-enabled technologies to address childhood obesity.

2. A situational analysis of physical activity in Oxfordshire’s children.

We worked with three primary schools across Oxfordshire and measured physical activity and sedentary time for 126 children in years five and six (age 9–11). We asked children to wear an IoT- based accelerometer (Axivity AX3) for seven days to assess habitual physical activity and sedentary behaviour. The Axivity AX3 measured sedentary, light, moderate, and vigorous physical activity.

After seven days we collected accelerometers and data were downloaded and processed. This method allowed us to assess two things at once: firstly, whether we could successfully use an IoT-based device to measure physical activity and secondly, to assess physical activity levels in Oxfordshire’s children.

3. Our third workstream involved producing visualisations of factors that could impact obesity in Oxfordshire’s children.

The most direct assessment of this was done using the Axivity AX3 data we collected and presenting it back to parents and children through an online survey (appendix 1) and an animated YouTube video we created to explain the results to children. In addition to this, we created an interactive map using ArcGIS StoryMaps where we integrated different datasets that could impact obesity in children.


Systematic review

Our systematic review provides an overview of the current use of IoT technologies for childhood obesity. We identified 23 full studies for our systematic review. The most used devices were smartphone/mobile apps (78.3%) and physical activity data (65.2%) from accelerometers (56.5%) were the most commonly tracked data. Mobile app-based data transfer (26.1%) was the most used method.

Over 50% of the studies employ simple statistical analysis whilst only one study utilised machine learning and deep learning methods in the service layer. Various stakeholders and user-specific use cases have been identified.

Game-based interventions have shown better effectiveness, but a decline of engagement in technology adoption was observed across most included studies. Adherence to IoT based approaches was low but game-based IoT solutions could play a pivotal role in addressing this.

Researcher-reported effectiveness measures vary greatly amongst studies, highlighting the importance for improved development and use of standardised digital health evaluation frameworks.

Physical activity in Oxfordshire’s children

Across the 126 children who participated in our situational analysis of physical activity in Oxfordshire’s children, we identified worryingly low levels of physical activity. 75% of the observed (awake) measurements were classified as sedentary, as shown in figure 1, 20% were light physical activity, and the remaining 5%were classified as moderate physical activity.

Pie chart

Figure 1. Activity levels of Oxfordshire children.

In addition to this, we examined the physical fitness of the children through the ‘beep test’, also known as a ‘shuttle run’ or ‘multi-stage fitness test’, where participants run back and forth between two markers 20m apart, keeping time with beeps that sound at progressively shorter intervals over the period of the test.

The results of this test highlighted worrying low levels of physical fitness compared to international peers, with measurements from over 100,000 children of the same age in 51 countries.

Figure 2 illustrates the beep test, and shows far lower running speeds in the Oxfordshire children measured, with an average running speed of 3.95/(km/hour) for Oxfordshire girls compared to an international average of 9.71, and running speed of 4.68/(km/hour) for Oxfordshire boys compared to an international average of 10.13.

Figure 2. Fitness level in Oxfordshire’s children (green) compared to International 20m SRT norms (blue) for running speed (km/h) at the last completed stage.

Deliverables and outputs

The systematic review (IoT-enabled technologies as an intervention for childhood obesity: a systematic review) has been submitted and is under review in IEEE Internet of Things Journal.

For the visual presentation of factors influencing obesity in Oxfordshire’s children, we took three different approaches aimed at different audiences.

  • Firstly, we wanted children to review and understand the evidence we gathered from the Axivity trackers. To this end, we used the data presented above and created an animated video we uploaded onto YouTube (openly available) to walk children through the results.

  • For teachers and parents, we created two and five page documents (available upon request) to present the results and these were followed by an online survey (appendix 1, available here). We unfortunately only received three responses from teachers and parents to the survey so we are not reporting the survey results because the number of responses is too small for us to draw any meaningful conclusions.

  • For policy makers and schools, we have created an interactive map using ArcGIS Storymap which incorporates different data, including the IoT data we collected at a school level.


Childhood obesity is one of the most serious public health challenges of the 21st century. In the United Kingdom, one in three children are obese or overweight when leaving primary school, which leads to greater medical spending for obesity-related diseases in childhood. This puts these individuals at risk of future health problems, particularly in people of lower socio-economic background.

Obesity was also recently recognised by the Prime Minister as a national priority because of the implications this has for the future of the UK.

Through our engagement with the Oxfordshire County Council, we have been able to integrate our project into the Oxfordshire Childhood Obesity Project Group (OCOPG), which aims to bring together stakeholders across Oxfordshire to explore how we can tackle childhood obesity from multiple angles.

We were able to demonstrate a clear route through which an IoT-enabled device (Axivity AX3) could be used to capture physical activity levels in children and then explored multiple ways of presenting this information back to stakeholders (children, parents, teachers, schools, council) to drive action.

In light of the national priority to tackle obesity, our results present a potentially scalable method to shed light on physical activity levels in the UK’s children, which could in turn be used to design programmes to increase physical activity to reduce obesity.

Next steps

Having established a method to capture physical activity levels in children using an IoT device, we now plan on expanding this to capture data from more schools in Oxfordshire through the OCOPG and other partners like Living Oxford, so we can get more representative data across Oxfordshire.

We are exploring the expansion of this work to other counties across the UK through our links with the Royal College of GPs.

Finally, we are exploring active travel as an intervention option to get children more active, while also contributing to the UK’s Net Zero commitments.

Lessons learned

What went well?

The Pitch-In project was a critical catalyst in helping us bring together a diverse group of stakeholders committed to a common mission. The dedication of the team to the project was essential in helping us to keep up the momentum despite facing setbacks, the principal of which was adapting to the COVID-19 lockdown and the shutting of schools.

What could have been done better?

Our engagement with parents and teachers for the survey was not as strong as we would have liked it to be – resulting in only three responses to our survey. Whilst the survey was undertaken during the COVID-19 lockdown when parents and teachers were distracted, we could have explored alternative means of getting responses from this key stakeholder group.

What would have been useful?

Some support on navigating existing open data sets in England/UK would have been helpful. It also would have been helpful to have some support for developing maps and exploring how best to integrate IoT data into existing data infrastructure.

What has Pitch-In done for you?

Pitch-In gave us an opportunity to bring together a diverse group of stakeholders committed to a common mission but for a project that traditional funders would likely not have funded. Pitch-In’s support served as a catalyst for us to build momentum for this essential work on tackling childhood obesity, which we will hopefully be able to continue developing over the coming months and years.

Project lead

Dr Richard Harrington – University of Oxford

Project partners

University of Oxford

Oxfordshire County Council

Oxford University Hospitals

Oxford Brookes University

The London Children and Young People’s Health Partnership

Oxford Academic Health Partners

View Oxfordshire Childhood Obesity Project Group’s recent report (PDF, 212KB).