03 Issues & Trends
Cereal Foods World, Vol. 63, No. 4
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Point: Glycemic Index—An Important but Oft Misunderstood Marker of Carbohydrate Quality
Effie Viguiliouk,1,2 Stephanie K. Nishi,1,2 Thomas M. S. Wolever,1–4 and John L. Sievenpiper1–5

1 Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada.
2 Toronto 3D Knowledge Synthesis and Clinical Trials Unit, Clinical Nutrition and Risk Factor Modification Centre, St. Michael’s Hospital, Toronto, ON, Canada.
3 Division of Endocrinology and Metabolism, Department of Medicine, St. Michael’s Hospital, Toronto, ON, Canada.
4 Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, ON, Canada.
5 Corresponding author. Dr. John L. Sievenpiper, MD, PhD, FRCPC, St. Michael’s Hospital, #6138-61 Queen St E, Toronto, ON M5C 2T2, Canada. Tel: +1.416.867.3732; Fax: +1.416.867.7495; E-mail: john.sievenpiper@utoronto.ca


The glycemic index (GI) is a measure of carbohydrate quality that is supported by many international health organizations for the management of chronic diseases and is included on food labels in several different countries to help consumers make healthier food choices. Despite its endorsement by various health and governmental organizations, the GI concept remains controversial. The aim of this article is to address the most recent criticisms of the GI related to its accuracy, precision, and role in cardiometabolic disease prevention and management. Many of the criticisms appear to stem from a misunderstanding of the GI and do not undermine the best evidence from prospective cohort studies and randomized controlled trials, which show important clinical and public health benefits of reducing the GI of the diet. 

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