The glycaemic index values of 3 different foods provided from a central location will be determined in each of 20-30 centers around the world. A standard protocol will be followed, but this protocol leaves room for variation in certain details, such as whether subjects are allowed to have coffee or tea with the test meals or only water, or the method of analyzing blood glucose. Methodologic details, subject demographic information (height, weight, age, and ethnicity), results of local calculations and raw data will be sent to a central location.