Institute of Global Health Innovation

By Professor Gary Frost, Chair in Nutrition and Dietetics, Faculty of Medicine, Department of Medicine, Imperial College London

The two states of malnutrition (under and over nutrition) account for a large percentage of non-communicable diseases worldwide. 65% of the world’s population live in countries where being overweight and obesity kills more people than those who are underweight. Obesity, the result of over nutrition, is no longer the preserve of high income countries with the prevalence of obesity now rising in low and middle income countries.

There is currently no population-based solution to this ever increasing problem. This, perhaps highlights the multifaceted nature of this disease, which cuts across economic standing, physical and food environment. Solutions that focus on one aspect of diet as an answer to this problem seem to fail. For example, the recent drive to decrease consumption of high sugar drinks through high taxation, seems to show after an initial decrease that there is a rebound with consumption rising and the purchase of other foods that are not in the tax portfolio. This highlights that population solutions many need to be multifaceted and address a number, of often very difficult economic, social and lifestyle problems at the same time

Our research, which again should be seen as only one part of a large jigsaw, focuses on how foods interact with the gastrointestinal tract to suppress appetite. In a number of systems approached to obesity, appetite regulation is a major driver. The gastrointestinal tract contains a number of specialised cells that produce a large amount of hormones that regulate appetite, PYY and GLP-1 for example. These specialised cells express a number of nutrient receptors which when stimulated cause release of these hormones. Our aim is to develop food ingredients that can trigger these hormones and suppress appetite and be used by large groups of people. If this can be achieved, then it could form part of a public health solution to weight gain. In partnership with the University of Glasgow, we have recently gathered proof of concept evidence that delivering short-chain fatty acids (molecules produced by bacteria in the colon from the fermentation of dietary fibre) can suppress appetite leading to reduced weight gain in overweight adults. The beauty of this method is that it uses common nutrients and the body’s own systems to enhance appetite regulation. Although a long way to go, this does give encouragement that targeting the delivery of certain nutrients into specific areas of the gastrointestinal tract could offer part of a population-based solution.