Nutritional influences on gut hormone release

Purpose of review: The prevalence of obesity is increasing in both developed and developing countries along with associated diseases such as type 2 diabetes and coronary heart disease. The recent discovery of a number of gut hormones that play a role in appetite regulation and are released or suppressed in response to a meal may offer new nutritional targets for weight management. Recent findings: This review focuses on the relationship between foods and nutrients and hormones released from the gastrointestinal tract. We have highlighted the effect of nutrients on gut hormones that are of specific interest: peptide YY, glucagon-like peptide 1, ghrelin and cholecystokinin. Summary; Cholecystokinin, peptide YY, glucagon-like peptide 1 and ghrelin are all affected by the intake of food. In response to single nutrient loads all are influenced by fat (to a lesser extent ghrelin). The effect of fat on cholecystokinin, peptide YY and ghrelin is to suppress appetite and food intake. In the case of glucagon-like peptide 1, however, dietary fat in some studies is linked to an increase in hunger rating, which contradicts the evidence that glucagon-like peptide 1 slows gastric emptying. This raises the possibility that gut hormones are regulating the flow of fat through the gastrointestinal tract with secondary effects on appetite. It is interesting to consider the long-term implications of this with regard to weight loss advice.