Tom Kirkwood studies why and how we age. He proposed the disposable soma theory to explain evolution of ageing, and pioneered the use of network approaches to investigate the complexity of its underlying mechanisms.

He initiated and led the Newcastle 85+ Study, a major population-based study of the biological, medical and social factors that together influence trajectories of health at older ages. His research has helped to explain both the apparent malleability of the ageing process and its intrinsic variability.

He is Emeritus Professor in Ageing at Newcastle University where he directed a multidisciplinary Institute for Ageing and Health and was Associate Dean for Ageing. He is an affiliate professor at the University of Copenhagen. He has engaged extensively in public and policy debate on how science can change attitudes to ageing and improve prospects for growing old more healthily.