Nutrition scientist; research interests are focused on how what we eat affects the risk of gaining weight or becoming obese and the interventions that might be effective to help people lose weight or reduce the risk of obesity-related diseases. Has also conducted a series of randomized controlled trials to study the impact of dietary changes on the risk factors for cardiovascular disease. In general, this work highlights that body weight is a more important risk factor for ill-health than differences in the nutritional composition of the diet. Scientific collaborations with the Behaviour and Health Research unit at the University of Cambridge and the MRC Human Nutrition Research unit, where was a Programme Leader for many years. Also interested in how scientific evidence on diet is translated into policy and practice, by government, industry, the public health community and the media. Former Science Adviser, Foresight obesity report and subsequently chaired the cross-government Expert Advisory Group on obesity and the Responsibility Deal Food Network. Member, Public Health England Obesity Programme Board; chairs a NICE Public Health Advisory Committee. Involved in events and media projects to engage the public in issues relating to diet and health. Recipient, OBE (2008) for services to public health.