The UK Biobank imaging study

The world's largest multi-modal imaging study

In 2014 the UK Biobank imaging study began with the aim of re-inviting 100,000 participants to undergo brain, cardiac and abdominal magnetic resonance imaging (MRI), dual-energy X-ray absorptiometry (DXA) and carotid ultrasound. Our target was reached in July 2025 and more than 105, 000 participants have now attended an appointment for imaging. Performing imaging at this scale is unprecedented and will allow researchers to identify associations between lifestyle and genetic factors and imaging-derived measures of body structure and function (i.e. ‘imaging-derived phenotypes’).

Imaging scans

UK Biobank's imaging study includes measures such as white matter hyper intensities derived from the brain scans, visceral fat derived from the abdominal scans, and left ventricular ejection fraction derived from the cardiac scans, along with measures of bone density from the DXA imaging. These derived measures can, in turn, be used to provide insights into the biological mechanisms through which lifestyle and genetic factors affect disease risk.

Repeat scans

In 2018 Dementias Platform UK (DPUK) funded repeat imaging scans on participants within 2 years after their initial scan. Obtaining a repeated imaging measure allows researchers to investigate associations between changes in imaging-derived phenotypes (e.g., brain morphology, heart function or visceral fat levels) and subsequent risk of disease. This was completed on 3,000 participants.

Together with the Medical Research Council (MRC); Calico Life Sciences, a biotechnology organization founded by Alphabet and Arthur D. Levinson; and the Chan Zuckerberg Initiative (CZI), a philanthropy founded by Priscilla Chan and Mark Zuckerberg, UK Biobank will undertake a project to conduct a repeat set of imaging scans on 60,000 UK Biobank participants. This £30m project, which began in 2023, will extend the DPUK project with a repeated set of highly-detailed, multi-organ images from a large cohort of participants, allowing researchers to assess changes in physiology over time. This effort will enable a better understanding of the trajectory of major chronic diseases of mid-to-later life and enable researchers to explore the mechanisms through which diseases occur in individuals. 

This study also added Optical Coherence Tomography (OCT), a measure of the eyes, as well as detailed imaging of the kidneys and a new technique to view blood flow inside the brain.

COVID-19 repeat imaging scans

UK Biobank repeat scans have already been used to better understand the health impacts of COVID-19. Repeat imaging has taken place on a subset of about 2,000 participants who had taken part in an imaging assessment prior to the pandemic. We received a 58% response rate from participants who had COVID-19 and a 57% response rate from participants who have not been infected but who were still similar in age, sex and ethnic group to help understand how the virus affects changes in internal organs.

Third imaging assessment

As the repeat imaging study progresses well, UK Biobank are now trialling a third imaging visit. This additional timepoint will help researchers better understand the trajectory for the various measures of health we hold, rather than having a simple linear measure over time we will now be able to see whether measured changes are  accelerating with age.

The UK Biobank Brain Health Study

The UK Biobank Brain Health Study looks to collect detailed information about the brain health of current UK Biobank participants. The data collected will help researchers identify different types of brain health conditions and support research into better ways to diagnose and treat conditions like dementia and Parkinson’s for future generations. You can read more about the brain health study on our website.