Modified Whey Protein and Effect on Post Meal Glucose Levels Study

After meals, the level of glucose rises in the circulation. In some individuals who are overweight and older, blood glucose can rise to levels which can damage tissues and cause health problems. Usually the hormone insulin, released from the pancreas, effectively lowers blood glucose. However, in overweight and older people insulin is less effective. Certain foods can lower the rise in blood glucose, particularly proteins. This works by increasing the release of a hormone from the gut called Glucagon-Like Peptide 1 (GLP-1), which in turn increases the release of insulin. A Component of milk left over after cheese making, termed Whey protein, is particularly good at releasing GLP-1. Whey protein is used as a food additive and taken as a supplement to help build muscle. Whey protein is a mixture of proteins which the investigators have modified to be more effective at lowering blood glucose. Using laboratory tests the investigators identified a protein present in Whey that does not increase levels of GLP-1 and removed it. It's removal raises the levels of other proteins which are more effective. In this study, the investigators would like to test the effectiveness of the "modified" whey protein. To do this, 30 older, overweight volunteers will be recruited and given the modified whey protein, a normal whey protein or a mixture of amino acids and then a breakfast meal to raise their blood glucose levels. These drinks will be given in a randomised sequence 1 week apart. On each visit, blood samples to measure blood glucose and related hormone levels will be taken. As GLP-1 can also have an effect on appetite, the investigators will measure the effect of the modified whey protein on subsequent appetite in the volunteers by asking them how hungry they feel.