Decreased insulin secretion is a key pathogenic factor in type 2 diabetes. Incretin hormones such as glucagon-like peptide-1 (GLP-1) are secreted from intestinal L-cells in response to a meal and play an important role in insulin release from pancreatic beta cells following a meal. The conditionally-essential amino acid glutamine is a potent stimulus of GLP-1 secretion in vitro and in vivo and previously we have demonstrated that ingestion of glutamine with or without a meal increases GLP-1 release in obese and non-obese humans with and without type 2 diabetes. When ingested with a low-fat meal, glutamine decreased postprandial glycaemia in parallel with insulin and GLP-1 increases in well-controlled type 2 diabetes patients. The aims of the present project are to determine whether daily glutamine supplementation has a cumulative effect on GLP-1 secretion in type 2 diabetes and to determine whether the effect of glutamine on insulin release is direct or mediated indirectly by GLP-1. The expected outcome of the project is to establish the naturally-occurring amino acid glutamine as a novel approach to stimulate secretion of GLP-1 and improve glycaemic control in type 2 diabetes.