61% of adults in Ireland are currently overweight or obese and almost a third of Irish children are now overweight, but there are some amazing people raising awareness of the issue. In this episode, Aoibhinn meets patient advocate Susie Birney who reveals the challenges of living with obesity and we hear from Dr Grace O'Malley and Dr Cathy Breen on the necessary approaches to tackling the obesity crisis. The links between obesity and diseases such as cancer and diabetes are well known, and Jonathan and Kathriona meet researchers Andrew Hogan and Lydia Dyck who are increasingly interested in the important role of our immune system – and our Natural Killer cells – in maintaining a healthy body weight.