Glycemic Index and the food industry: A current review

One of the 'buzz words' increasingly used in connection with foods is Glycemic Index or "GI". The GI rating method allows carbohydrate-containing foods to be given a numerical value based on their effect on postprandial blood glucose level relative to each other, and was originally defined to aid in the management of diabetes (Jenkins & others 1983). The GI has been adopted by many food manufacturers for advertising purposes, as well as by health professionals concerned with dietary carbohydrate intake, although some confusion exists amongst both industry and the public regarding the exact meaning of the term and how it might assist in food selection. The validity of the GI has also been questioned, as many factors may affect the precision of an assay based on testing in humans. These factors include methodological issues, exercise level, degree of body fat and reproductive hormone status, as well as the food composition. This article reviews factors influencing the GI and its measurement and the implications of these for consumer health and for the food and allied industries.