Professor Julian Mercer


Professor Julian Mercer

Dietary behaviour and molecular mechanisms

Consuming too many calories is the main cause of obesity in the human population but we are investigating whether food can be part of the solution, rather than just part of the problem.  Communication between the gut and the brain lies at the heart of the controlling hunger and appetite and what we eat not only influences this communication, but is also influenced by it. We are conducting a range of studies to examine the food-gut-brain cycle in more detail. 

The results could help food manufacturers make healthier products which should, in turn, help consumers to limit calorie intake.

FHIS Science Bytes - Prof. Julian Mercer video

The cause of obesity in most people is not mutations or polymorphisms in a single gene, but rather the interaction of genetic susceptibility (multiple genes) with environment, where diet is clearly a very influential component, driving over-consumption of calories (energy). Behaviour change (especially in terms of food consumption) is often advocated as essential for long-term resolution of the overweight and obesity issue in the majority of the population. We need strategies for supporting behaviour change that result in beneficial reduction in caloric intake and a shift towards healthier food choices. With Scottish Government funding we will pursue an integrated programme of pre-clinical and human volunteer studies to investigate the psychological, metabolic and physiological characteristics of individuals with specific habitual dietary intakes, and the effect of adopted changes in diet choice on these processes. We will also investigate how dietary choice decisions are made under conditions of caloric restriction i.e. during weight loss attempts, to identify strategies to support these efforts.

NeuroFAST  - NeuroFAST( is a project funded by the European Union Seventh Framework Programme under grant agreement n° 245009. Duration April 2010-March 2015.

Full4Health – Full4Health is a project funded by the European Union Seventh Framework Programme under grant agreement n° 266408. Duration February 2011-January 2016. See for more details.

Herwig, A., de Vries, E.M., Bolborea, M., Wilson, D., Mercer, J.G., Ebling, F.J.P., Morgan, P.J., Barrett, P. (2013) “Hypothalamic ventricular ependymal thyroid hormone deiodinases are an important element of circannual timing in the Siberian hamster (Phodopus sungorus).” PloS One,  8 (4 Art. e62003)

Bake, T., Duncan, J.S., Morgan, D.G.A., Mercer, J.G. (2013) “Arcuate nucleus homeostatic systems are not altered immediately prior to the scheduled consumption of large, binge-type meals of palatable solid or liquid diet in rats and mice.” Journal of Neuroendocrinology, 25 (4) pp. 357-371

Wagner, G., Bird, S.P., Mercer, J.G. (2013) “EU obesity research explores food-gut-brain mechanisms.” Food Technology, 67 (3) pp. 22

Bird, S.P., Murphy, M., Bake, T., Albayrak, O. Mercer, J.G. (2013) “Getting science to the citizen – ‘Food addiction’ at the British Science Festival as a case study of interactive public engagement with high profile scientific controversy.” Obesity Facts, 6(1) pp. 103-108

Helwig, M., Herwig, A., Heldmaier, G., Barrett, P., Mercer, J.G., Klingenspor, M.  (2013) “Photoperiod-dependent regulation of carboxypeptidase E affects selective processing of neuropeptides in the seasonal Siberian hamster (Phodopus sungorus).” Journal of Neuroendocrinology, 25 (2) pp. 190-197

Research briefs for the Knowledge Scotland web site

EU funded projects

NeuroFAST is a project funded by the European Union Seventh Framework Programme. This project examines the Integrated Neurobiology of Food Intake, Addiction and Stress. This multidisciplinary project will explore the neurobiology of addiction and eating behaviour and the complex socio-psychological forces that can lead to its dysregulation. These forces include dietary components (e.g. highly palatable foods and alcohol), some of which may have addictive properties, but also cultural and social pressures and cognitive-affective factors (perceived stress and stress regulation, anxiety and depression), and family-genetic influences on these. The project will provide new data from human studies that is needed to inform health policy initiatives, underpinned by mechanistic research to establish a solid scientific basis for this advice.

Full4Health is a project funded by the European Union Seventh Framework Programme. This project, co-ordinated by the Rowett, will examine the interactions between food and the gut-brain signalling of hunger and satiety (feeling full). Work will encompass pre-clinical models and human volunteer studies where studies will be conducted across a range of age groups, from children to the elderly, with physiological and psychological measures related to and influencing food choice.

The potential to manipulate the mechanisms of hunger and satiety through diet is directly relevant to any policy concerned with obesity, since that condition is largely driven by over-consumption of food. Supporting adequate nutrition in particular clinical circumstances and in the elderly is also a growing concern. The outputs from this project will therefore address vulnerable sectors of the population such as children and the elderly. The results from the project have the potential to enable the development of novel diets, food or supplements, founded on a sound evidence base.


Julian frequently presents the Rowett research programme to a wide range of audiences including industry and policy stakeholders, and the public in his capacity as Research Theme Leader. He was a speaker at the ‘Science of Eating’ event held at the Scottish Parliament in August 2010 as part of the Festival of Politics and at the British Neuroscience Association Christmas Symposium entitled ‘Food, Glorious Food!’ at the Royal Society, London in December 2011.

Julian is on the steering committee of the British Society for Neuroendocrinology, chairs the Outreach group of the Society, and is leading on the development of a new website for the Society with membership and public engagement content.