Nutrition and Behaviour Unit web pages

ResearchGate profile

My research focuses on psychobiological controls of food choice and food intake, and on how underlying principles inform our understanding of human appetite and energy balancing (including obesity). Animal models indicate that associative learning plays a critical role in dietary behaviour and my work has pioneered the study of this process in humans. Researchers with an interest in energy balance have tended to focus on biological and psychological processes that terminate a meal. My work suggests that these prandial events are less relevant in humans because meal size is more often determined before a meal begins. From this, it follows that to understand energy intake we need to appreciate the cognitive activity associated with decisions about portion size.

In particular, and with support from the BBSRC (2009-2017), my group have shown that ‘expected satiation’ and ‘expected satiety’ are key drivers of the number of calories that we put on our plate (perhaps even more important than palatability). To complement this work, my group have also explored the effects of eating behaviour on food intake, with a particular focus on the mechanism by which rate of eating influences food choice and appetite.

More recently, several of my projects have addressed questions about our modern food environment. Modern commercial foods are very unlike those that our forebears would have encountered. Not only do they differ in sensory and physical properties, but they also tend to be much more energy dense (calories per gram), and they are available in numerous different portion sizes, brands, and varieties. Much of my work has focused on whether modern humans are well adapted to these new foods and how they come to influence dietary decisions that promote a poor diet and overconsumption. This work started in 2014 as part of a collaborative 5-year EU-funded project called Nudge-it, and it continues in different forms today.

In the Nutrition and Behaviour Unit we tend to study people who have only ever been exposed to a Western diet. A concern is that we might overlook important detail or, worse still, we might draw general conclusions that don’t translate to other cultures. To address this issue we have conducted field research involving the Samburu - a population of semi-nomadic pastoralists who live in a remote area of Kenya. More recently, our reach has extended to comparisons in China and beyond.

Since 2017 my group has also teamed up with others to form the NIHR Bristol Biomedical Research Centre. Currently, I co-lead a Population Diet and Physical Activity workstream, that forms part of the Diet and Physical Activity Theme of the Bristol NIHR BRC. Our work focuses on the early development of population-level interventions aimed at modifying diet and physical activity habits. 

In the last few years I have also become interested in ways to translate my fundamental research to create sustainable food systems by adapting consumer behaviour. As part of this process my group are currently creating a ‘consumer lab’, which enables researchers to study the effects of dietary or behavioural interventions in a real-world commercial food outlet. Forming part of the UKRI UK Transforming UK Food Systems Network, I am leading a 3-year project called SNEAK (Sustainable Nutrition, Environment, and Agriculture, without consumer Knowledge). Our work is exposing the potential to reorder meal options on a weekly menu to effect improvements in dietary intakes and carbon footprint. Ultimately, our objective is to develop a process that will enable organisations such as schools and hospitals to optimise their menus to bring about marked reductions in unwanted characteristics such as carbon emissions and intake of saturated fatty acids. Because our work relies on subtle manipulations to menu structures, we think we can achieve this ‘sneaky’ approach without consumers even being aware, and without the need to reformulate or change meal options.

Finally, poor diet has a dramatic impact on the prevalence of non-communicable diseases. The UK is recognised for its strength in research relating to social and psychological drivers of dietary behaviour, and this has considerable potential to be applied by the food industry to deliver population-wide benefits. To build capacity in this area, I am leading a 5-year Consumer Lab, which is one of six innovation hubs that form the BBSRC Diet and Health Open Innovation Research Club (OIRC). By studying real-world food choices and everyday dietary behaviours, my vision is to develop a distributed network of industry and academic members that can work together to foster the application of academic research in ways that benefit both industry and the consumer.

Awards

Alan N. Epstein Award - Society for the Study of Ingestive Behavior (2011). Awarded in recognition of a specific research discovery that has advanced the understanding of ingestive behaviour.

Hoebel Prize for Creativity - Society for the Study of Ingestive Behavior (2023). Awarded in recognition of research that has the potential to benefit society by elucidating methods for treating or preventing disorders of ingestive behaviour, while demonstrating an exceptional level of creativity.