Scientists in Aberdeen are about to embark on a unique research project which will assess how our brains respond when we lose weight using high protein, low carbohydrate, Atkins-type diets.
The aim is to develop healthy, weight-loss diets, which are more satisfying and so reduce the likelihood of snacking and breaking the diet. Twelve overweight men, aged fifty or over, are needed to take part in the study.
The project brings together the combined expertise of scientists from Aberdeen’s Rowett Research Institute, The Robert Gordon University and The University of Aberdeen and will examine how the appetite-controlling areas of the brain respond during the consumption of high-protein diets.
Men who volunteer to take part will undergo a nine-week residential weight-loss study at the Human Nutrition Unit at the Rowett Research Institute. They will also attend the John Mallard Scottish PET (Positron Emission Tomography) Centre at the University of Aberdeen for a PET scan of their brain. The scan will reveal the activity of the appetite-controlling areas of the brain during the weight-loss study.
“Many scientists now accept that weight loss on high-protein, low-carbohydrate diets, is because people satisfy their hunger after eating less calories than they would normally eat. This has stimulated our interest in the mechanisms that control appetite and the feeling of being full,” said Dr Alex Johnstone from the Rowett Institute, who is leading the study.
“We know that when people eat low carbohydrate diets, within a relatively short time their body has to switch from using glucose as a fuel to using a by-product of fat metabolism called ketone bodies. Ketone bodies are appetite-suppressing and this may be because they affect the appetite centres in the brain. We also know that protein itself is very good at making people feel full. So are high-protein, low-carbohydrate diets particularly effective because of the combined effect of the protein and the ketone bodies? Unravelling these mechanisms will help the development of healthy weight loss diets, which are more satisfying, and reduce hunger pangs. This means it is less likely that people will be tempted to snack and break their diet,” said Dr Johnstone.
“PET scanning is a medical imaging technique which can be used to look non-invasively inside the body and study its metabolism. The PET scans we take during this study will show if the appetite centres in the volunteers’ brains respond differently depending on the weight-loss diets they are eating. This in turn will indicate whether the carbohydrate levels in the high-protein diets are important,” said Dr Andy Welch who is Senior Lecturer in the School of Medical Sciences at the University of Aberdeen.
Professor Iain Broom, Consultant at NHS Grampian and Professor at Robert Gordon University, who is an expert in the clinical treatment of obesity said: “This study will further develop our understanding of the processes of body weight regulation and should help us to refine weight-loss protocols and provide appropriate targeting of treatment to obese patients.”
Dr Johnstone is looking for twelve healthy, overweight men, aged 50 and over, to take part in the study. Volunteers will reside at the Rowett’s Human Nutrition Unit for the nine weeks of the trial, which is based in Bucksburn on the outskirts of Aberdeen. All food and accommodation is provided free. An ideal opportunity for people living outside Aberdeen to visit the city and surrounding area for a protracted break!
The study is funded by the Scottish Executive Environment and Rural Affairs Department (Rowett Research Institute) and by a grant from the Chief Scientists Office.