UK Biobank completes world’s largest population imaging study to support disease research and diagnosis

UK Biobank has completed the world’s largest population-based imaging study, collecting over one billion scans from 100,000 volunteers. By combining these imaging data with genetic, lifestyle and clinical information, the project is supporting research into earlier disease detection, more accurate diagnosis, and a better understanding of how health changes over time.

Launched in 2014 with a pilot phase, the full-scale project began in 2016 and represents over a decade of effort, involving 100,000 five-hour imaging appointments and more than £60 million in funding. The final scan took place in July 2025 at the Reading Imaging Centre.

“This is a mammoth achievement, and the wealth of data that will be made available to researchers thanks to these volunteers will transform our understanding of diseases like cancer and dementia, which cause heartache for so many families,” said Peter Kyle, Science and Tech Secretary, UK Government.

Each volunteer underwent a series of advanced MRI scans capturing over 12,000 images of the brain, heart, and abdomen, along with whole-body scans to measure bone density and body fat, and an ultrasound of the carotid arteries. These imaging data are combined with detailed information already collected from the same participants over the past 15 years, including lifestyle factors, physical measures such as height, weight and grip strength, medical history, blood proteins, and genetic data. Together, these datasets allow researchers to explore how all aspects of life influence health and how and when diseases develop.

“The unprecedented scale of this imaging project – more than 10 times bigger than anything that existed before – makes it possible for scientists to see patterns of disease that just couldn’t otherwise be seen,” explained Professor Sir Rory Collins, UK Biobank’s Principal Investigator and Chief Executive.

Over 1300 peer-reviewed studies have been published using UK Biobank imaging data, with research already supporting improvements in clinical practice. NHS memory clinics across the UK have adopted processes based on brain MRI developed through UK Biobank, including a modified protocol at the Oxford Brain Health Clinic that improves image quality and aligns more closely with clinical reporting, creating a high-quality source of real-world data (RWD) for both care and research.

In cardiovascular medicine, an AI tool trained on UK Biobank data is now used at over 1700 sites in more than 90 countries. This technology allows clinicians to analyze heart scans in less than one second, compared with approximately 15 minutes using traditional methods. Studies have also shown that machine learning techniques can provide measurements of cardiac structure and function with a level of precision similar to expert clinicians, while significantly reducing analysis time. These findings are supporting the broader use of automated imaging tools in clinical and research settings.

“The beauty of UK Biobank is the breadth of the data collected from the generous volunteers, and the imaging scans add another layer of exquisite detail,” said Professor Paul Matthews, Chair of the UK Biobank Imaging Working Group.

Researchers are using UK Biobank imaging data to identify new disease markers, improve diagnostic tools powered by AI, and gain a clearer picture of how the body changes before symptoms appear. By combining MRI with other health data and applying machine learning techniques, scientists have been able to predict the early onset of 38 diseases. AI models have been developed to create personalized versions of healthy organs, such as the heart, based on an individual’s age, sex, weight, and height, helping to detect early signs of disease.

The imaging data are also revealing how organs can be biologically older than a person's actual age, providing insight into which parts of the body may be at risk of future disease and how interventions might be targeted. Studies have identified associations between structural changes in the heart and an increased risk of psychiatric conditions such as depression, improving understanding of heart–brain interactions.

Other findings include the use of MRI as a non-invasive alternative to diagnose and monitor fatty liver disease, and the identification of aortic calcification in one in ten middle-aged individuals with no symptoms. Research has also shown how alcohol consumption, even in low amounts, may contribute to reductions in brain size, and how people with the same BMI can store fat in very different ways depending on their genetic profile. Together, these discoveries underscore how large-scale imaging and RWD are advancing earlier disease detection and supporting more personalized approaches to prevention and care.

“UK Biobank’s imaging study has transformed the landscape of biomedical research forever,” said Professor Louise Thomas, Professor of Metabolic Imaging, University of Westminster. “The sheer volume of data propelled major advances in computerized image analysis. Now researchers can measure the size, shape, and composition of nearly every organ and tissue in the body in seconds, rather than hours per person.”

The data have also accelerated global access to imaging research. According to Professor Naomi Allen, UK Biobank’s Chief Scientist, the project has enabled researchers in diverse fields, including those in lower-income countries and outside of medical imaging, to make use of the data through simplified, cloud-based access.

Participant engagement has been crucial to the project’s success. Alison, a member of the UK Biobank Participant Advisory Group, commented:

“I signed up to my imaging appointment because I want to help create a healthier future for all of us to enjoy… to be of use to scientists who are working hard to help future generations.”

The imaging project continues with a follow-up phase, launched in 2022, aiming to perform repeat scans on 60,000 of the original participants by 2029. These repeat scans will help researchers track changes over time, further strengthening the study’s potential to reveal how early signs of disease develop.

Rachel McKendry, Executive Director of Discovery, Wellcome, emphasized the importance of the initiative:

“Combining these images with the genetic and lifestyle data offers unprecedented potential to unlock new discoveries and transform our understanding of health to improve lives around the world.”

UK Biobank’s imaging data will be fully released to approved researchers via the secure UK Biobank Research Analysis Platform by the end of 2025, supporting ongoing research into the study, diagnosis, and prevention of disease.