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Dr. Thomas Wolever, MD, PhD, DM (Oxford)



Dr. Wolever obtained his medical degree from Oxford University, England in 1980. During this time he became interested in the potential role of dietary fiber to prevent and treat chronic diseases such as heart disease, cancer and diabetes. He took a year off from his medical studies to do an MSc on the effects of dietary fiber on blood glucose responses under the supervision of Dr. David Jenkins. As part of his MSc research, he helped design and conduct the first study showing that the ability of fiber to reduce blood glucose and insulin responses was related to its viscosity, and also the first successful study to use purified fiber supplements to treat diabetes mellitus. In addition, before completing medical school, Dr. Wolever was involved in the development of the Glycemic Index, playing a major role in the data analysis for the first paper on GI published in 1981.

Dr. Wolever obtained his PhD in Nutritional Sciences from the University of Toronto in 1986, researching the validity of the GI concept. He obtained a Doctorate in Medicine from Oxford University in 1993. Dr. Wolever was first appointed to a faculty position in the Department of Nutritional Sciences, University of Toronto in 1986, and was promoted to full professor in 1998. He has been a member of the medical staff at St. Michael’s Hospital in the Division of Endocrinology and Metabolism since 1987. From the beginning of his research career, Dr. Wolever has had a special interest in diabetes, and has been an active volunteer for the Canadian Diabetes Association for many years. He has served as a member of the National Nutrition Committee from 1984-87 and its Chair from 1996-2000. He also sat on the Grants Committee from 1995-1999; on the Council of the Clinical & Scientific Section from 1996-98; on the Planning Committee for CDA Professional Conference in 1998; and on the committee for the Revision of clinical practice guidelines in 1997-98 and again in 2002-03. He was also a member of the Personal Awards Committee from 2000-2005. Dr. Wolever was an expert consultant and appointed Rapporteur for the FAO/WHO Expert Consultation on Carbohydrates held in Rome in 1997.

Dr. Wolever is author or co-author of over 280 peer-reviewed publications and over 50 chapters and review articles. Dr. Wolever’s peer-reviewed publications have been cited over 6500 times, for an average of over 35 citations per article. Dr. Wolever is also the author of a scientific book entitled: The Glycaemic Index: A Physiological Classification of Dietary Carbohydrate published in 2006 by CABI.

Dr. Wolever’s research concerns the role of dietary carbohydrates in human nutrition and metabolism, with particular interest in insulin resistance and diabetes. Dr. Wolever’s major research interests are how different types and amounts of nutrients, and especially carbohydrates (sugars, starch, dietary fiber) influence systemic metabolism with particular reference to insulin resistance, obesity, diabetes and hyperlipidemia. One of his major goals is to improve the quality of the evidence for the role of nutrition in health, and he believes this can best be accomplished through collaboration with others.

Dr. Wolever’s research expertise includes: the assessment of dietary intakes, especially of dietary fiber, glycemic index and glycemic load; metabolic assessment of human subjects, especially postprandial responses, insulin secretion, insulin sensitivity and colonic fermentation; determination of the glycemic index of foods; and clinical trials. He has extensive experience coordinating central laboratory facilities and organizing international laboratory cross-validation programs and multi-center clinical trials.

Dr. Wolever founded Glycaemic Index Testing, Inc. in 1997 to provide confidential research services of high scientific quality to industry in order to educate industry about GI, promote the use of the GI and help develop low GI food products. In order to provide an expanded range of research services and cope with increased demand, Dr. Wolever partnered with Drs. Alexandra Jenkins and Vladimir Vuksan to form GI Labs in 2004.

Dr. Thomas Wolever


Augustin LSA, Kendall CWC, Jenkins DJA, Willett WC, Astrup A, Barclay AW, Björck I, Brand-Miller JC, Brighenti F, Buyken AE, Ceriello A, La Vecchia C, Livesesy G, Liu S, Riccardi G, Rizkalla SW, Sievenpiper JL, Trichopoulou A, Wolever TMS, Baer-Sinnot S, Poli A. Glycemic index, glycemic load and glycemic response: an international scientific consensus summit from the International Carbohydrate Quality Consortium (ICQC). Nutr Metab Cardiovasc Dis 2015; 25(9):795-815.

Lewis EJ, Radonic PW, Wolever TMS, Wells GD. 21 days of mammalian omega-3 fatty acid supplementation improves aspects of neuromuscular function and performance in male athletes compared to olive oil placebo. J Int Soc Sports Nutr 2015;12:28. doi: 10.1186/s12970-015-0089-4.

Wolever TMs, Giddens JL, Sievenpiper JL. Effect of ethnicity on glycaemic index: a systematic review and meta-analysis. Nutr Diab 2015;5:e170; doi:10.1038/nutd.2015.21.

Jayalath VH, de Souza RJ, Ha V, Mirrahimi A, Blanco-Mejia S, Di Buono M, Jenkins AL, Leiter LA, Wolever TM, Beyene J, Kendall CW, Jenkins DJ, Sievenpiper JL. Sugar-sweetened beverage consumption and incident hypertension: a systematic review and meta-analysis of prospective cohorts. Am J Clin Nutr 2015;102:914-21.

Padhi EMT, Blewett HJ, Duncan AM, Guzman RP, Hawke A, Seetharaman K, Tsao R, Wolever TMS, Ramdath DD. Whole soy flour incorporated into a muffin and consumed at 2 doses of soy protein does not lower LDL cholesterol in a randomized, double-blind controlled trial of hypercholesterolemic adults. J Nutr 2015, e-pub ahead of print as doi: 10.3945/jn.115.219873.

Padhi EMT, Ramdath DD, Carson SJ, Hawke A, Blewett HJ, Wolever TMS, Vella D, Seetharaman K, Duizer LM, Duncan AM. Liking of soy flour muffins over time and the impact of a health claim on willingness to consume. Food Res Int 2015;77:491-97.

Priyadarshini M, Thomas A, Reisetter AC, Scholtens DM, Wolever TM, Josefson JL, Layden BT. Maternal short chain fatty acids are associated with metabolic parameters in mothers and newborns. Transl Res 2014;164:153-57.

Fernandes J, Su W, Rahat-Rozenbloom S, Wolever TMS, Comelli E. Adiposity, gut microbiota and faecal short chain fatty acids are linked in adult humans. Nutrition & Diabetes 2014;4:e121; doi:10.1038/nutrd.2014.23.

Rahat-Rozenbloom S, Fernandes J, Gloor G, Wolever TMS. Evidence for greater production of colonic short chain fatty acids in overweight than lean humans. Int J Obesity 2014;38:1525-31.

Jayalath VH, Sievenpiper JL, de Souza RJ, Ha V, Mirrahimi A, Santaren ID, Mejia SB, Di Buono M, Jenkins AL, Leiter LA, Wolever TMS, Beyene J, Kendall CWC, Jenkins DJA. Total fructose intake and risk of hypertension: a systematic review and meta-analysis of prospective cohorts. J Am Col Nutr 2014;33:328-39.

Whitehead A, Beck EJ, Tosh S, Wolever TMS. Cholesterol-lowering effects of oat β-glucan: a meta-analysis of randomized controlled trials. Am J Clin Nutr 2014;100:1413-21.

Wolever TMS, Sievenpiper JL. Revised food labeling in North America: the blind leading the blind? Eur J Clin Nutr 2014;68:1275-76.

Wolever, TMS. Glycemic index claims on food labels: review of Health Canada's evaluation. Eur J Clin Nutr 2013; 67: 1229-33.

Wolever TMS. Glycemic index claims on food labels: review of Health Canada's evaluation. Eur J Clin Nutr 2013.

Wolever TMS. Is glycaemic index (GI) a valid measure of carbohydrate quality? Eur J Clin Nutr 2013;67:522-31.

Wolever TMS, Gibbs AL, Chiasson J-L, Connelly PW, Josse RG, Leiter LA, Maheux P, Rabasa-Lhoret R, Rodger NW, Ryan EA. Altering source or amount of dietary carbohydrate has acute and chronic effects on postprandial glucose and triglycerides in type 2 diabetes: Canadian trial of Carbohydrates in Diabetes (CCD). Nutr Metab Cardiovasc Dis 2013;23:227-34.

Tran S, Wolever TMS, Errett LE, Ahn H, Mazer D, Keith M. Preoperative carbohydrate loading in patients undergoing coronary artery bypass or spinal surgery. Anesth Analg 2013 epub ahead of print

Kwong MGY, Wolever TMS, Brummer Y, Tosh SM. Increasing the viscosity of oat β-glucan beverages by reducing solution volume does not reduce glycaemic responses. Brit J Nutr 2013;110:1465-71.

Fernandes J, Wang A, Su W, Rozenbloom SR, Taibi A, Comelli EM, Wolever TMS. Age, dietary fiber, breath methane and fecal short chain fatty acids are interrelated in Archaea-positive humans. J Nutr 2013;143:1269-75.

Aldughpassi A, Abdel-Aal el-SM, Wolever TMS. Barley cultivar, kernel composition, and processing affect the glycemic index. J Nutr 2012;142:1666-71.

Ha V, Sievenpiper JL, de Souza RJ, Chiavaroli L, Wang DD, Cozma AI, Mirrahimi A, Yu ME, Carleton AJ, Dibuono M, Jenkins AL, Leiter LA, Wolever TMS, Beyene J, Kendall CWC, Jenkins DJA. Effect of fructose on blood pressure: a systematic review and meta-analysis of controlled feeding trials. Hypertension 2012;59: 787-95.

Kochan AM, Wolever TMS, Chetty VT, Anand SS, Gerstein HC, Sharma AM. Glycemic index predicts individual glucose responses after self-selected breakfasts in free-living abdominally obese adults. J Nutr 2012;142:27-32.

Wolever TMS, Gibbs AL, Brand-Miller J, Duncan AM, Hart V, Lamarche B, Tosh SM, Duss R. Bioactive oat β-glucan reduces LDL cholesterol in Caucasians and non-Caucasians. Nutr J 2011;10:130-133.

Brenner DR, Arora P, Garcia-Bailo B, Wolever TMS, Morrison H, El-Sohemy A, Karmali M, Badawi A. Plasma vitamin D levels and risk of metabolic syndrome in Canadians. Clin Invest Med 2011;34:E377-E384.

Kinnear T, Wolever TMS, Murphy AM, Sullivan JA, Liu Q, Bizimungu B. Effect of preparation method on the glycaemic index of novel potato clones. Food & Function 2011:2:438-44.

Regand A, Chowdhury Z, Tosh SM, Wolever TMS, Wood P. The molecular weight, solubility and viscosity of oat beta-glucan affect human glycemic response by modifying starch digestibility. Food Chem 2011;129:297-304.

Chiu CJ, Liu S, Willett WC, Wolever TM, Brand-Miller JC, Barclay AW, Taylor A. Informing food choices and health outcomes by use of the dietary glycemic index. Nutr Rev 2011;69:231-42.

Lan-Pidhainy X, Wolever TMS. Are the glycemic and insulinemic index values of carbohydrate foods similar in healthy control, hyperinsulinemic and type 2 diabetic patients? Eur J Clin Nutr 2011;65:727-34.

Wolever TMS, Mullan YM. Sugars and fat have different effects on postprandial glucose responses in normal and type 1 diabetic subjects. Nutr Metab Cardiovasc Dis 2011;21:719-25.

Grant SM, Wolever TMS, O'Connor DL, Nisenbaum R, Josse JG. Effect of a low glycaemic index diet on blood glucose in women with gestational hyperglycaemia. Diab Res Clin Prac 2011;91:15-22.

Jenkins AL, Kacinik V, Lyon M, Wolever TMS. Effect of adding the novel fiber, PGX, to commonly consumed foods on glycemic response, glycemic index and GRIP: a simple and effective strategy for reducing post prandial blood glucose levels - a randomized, controlled trial. Nutr J 2010;9:58. 2011.

Jenkins AL, Kacinik V, Lyon MR, Wolever TMS. Reduction of postprandial glycemia by the novel viscous polysaccharide PGX, in a dose-dependent manner, independent of food form. J Am Col Nutr 2010;29:92-98.

Wolever TMS, Tosh SM, Gibbs AL, Brand-Miller J, Duncan AM, Hart V, Lamarche B, Thomson BA, Duss R, Wood PJ. Physicochemical properties of oat β-glucan influence its ability to reduce serum LDL cholesterol in humans: a randomized clinical trial. Am J Clin Nutr 2010;92:723-32.

Ley SH, Harris SB, Connelly PW, Mamakeesick M, Gittelsohn J, Wolever TM, Hegele RA, Zinman B, Hanley AJ. Association of apolipoprotein B with incident type 2 diabetes in an aboriginal Canadian population. Clin Chem 2010;56:666-70.

Tarini J, Wolever TMS. The fermentable fibre inulin increases postprandial serum short-chain fatty acids and reduces free-fatty acids and ghrelin in healthy subjects. Appl Physiol Nutr Metab 2010;35:9-16.

Lan-Pidhainy X, Wolever TMS. The hypoglycemic effect of fat and protein is not attenuated by insulin resistance. Am J Clin Nutr 2010;91:98-105.

Wolever TMS, Tosh SM, Gibbs AL, Brand-Miller J, Duncan AM, Hart V, Lamarche B, Thomson BA, Duss R, Wood PJ. Physicochemical properties of oat beta-glucan influence its ability to reduce serum LDL cholesterol in humans: a randomized clinical trial. Am J Clin Nutr 2010; in press.

Tosh SM, Miller S, Brummer Y, Regand A, Deflice C, Duss R, Wolever TMS, Wood PJ. Processing affects physiochecmical properties of beta-glucan in oat bran cereal. J Agric Food Chem. 2010; 58: 7723-30.

Freeland KR, Wilson C, Wolever TMS. Adaptation of colonic fermentation and glucagon-like peptide-1 secretion with increased wheat fibre intake for 1 year in hyperinsulinaemic human subjects. Brit J Nutr. 2010;103:82-90.

Fontaine-Bisson B, Wolever TM, Connelly PW, Corey PN, El-Sohemy A.  NF-kappaB -49Ins/Del ATTG polymorphism modifies the association between dietary polyunsaturated fatty acids and HDL-cholesterol in two distinct populations.  Atherosclerosis 2009;204:465-470.

Eny KM, Wolever TMS, Fontaine-Bisson B, El-Sohemy A.  Genetic variant in the glucose transporter type 2 is associated with higher intakes of sugars in two distinct populations.  Physiol Genomics 2008;33:355-60.

Tully V, Wolever TMS, Darling P, Errett L, Keith ME.  Pre-operative modification of dietary glycemic index improves pre but not post-operative indices of insulin resistance in patients undergoing coronary artery bypass graft surgery.  J Am Coll Nutr.  2008 Feb; 27(1): 168-76.

Wolever TMS, Mehling C, Chiasson JL, Josse RG, Leiter LA, Maheux P, Rabasa-Lhoret R, Rodger NW, Ryan EA.  Low glycaemic index diet and disposition index in type 2 diabetes (the Canadian trial of carbohydrates in diabetes): a randomized controlled trial.  Diabetologia. 2008 Sep; 51(9): 1607-15. 

Wolever TMS, Gibbs AL, Mehling C, Chiasson JL, Connelly PW, Josse RG, Leiter LA, Maheux P, Rabasa-Lhoret R, Rodger NW, Ryan EA.  The Canadian Trial of Carbohydrates in Diabetes (CCD), a 1-y controlled trial of low-glycemic-index dietary carbohydrate in type 2 diabetes: no effect on glycated hemoglobin but reduction in C-reactive protein.  Am J Clin Nutr.  2008 Jan; 87(1): 114-25.

Freeland KR, Anderson GH, Wolever TMS.  Acute effects of dietary fibre and glycaemic carbohydrate on appetite and food intake in healthy males.  Appetite.  2008 Aug 7.

Eny KM, Wolever TMS, Fontaine-Bisson B, El-Sohemy A.  Genetic variant in the glucose transporter type 2 is associated with higher intakes of sugars in two distinct populations.  Physiol Genomics.  2008 May 13; 33(3): 355-60. 

Wolever TMS, Brand-Miller JC, Abernethy J, Astrup A, Atkinson F, Axelsen M, Bjorck I, Brighenti F, Brown R, Bryne R, Brynes A, Casiraghi MC, Cazaubiel M, Dahlqvist L, Delport E, Denyer GS, Erba D, Frost G, Granfeldt Y, Hampton S, Hart VA, Hatonen KA, Henry CJ, Hertzler S, Hull S, Jerling J, Johnston KL, Lightowler H, Mann N, Morgan L, Panlasigui LN, Pelkman C, Perry T, Pfeiffer AF, Pieters M, Ramdath DD, Ramsingh RT, Robert SD, Robinson C, Sarkkinen E, Scazzina F, Sison DC, Sloth B, Staniforth J, Tapola N, Valsta LM, Verkooijen I, Weickert MO, Weseler AR, Wilkie P, Zhang J.  Measuring the glycemic index of foods: interlaboratory study.  Am J Clin Nutr.  2008 Jan;87(1):247S-257S.

Fontaine-Bisson B, Wolever TMS, Chiasson JL, Rabasa-Lhoret R, Maheux P, Josse RG, Leiter LA, Rodger NW, Ryan EA, Connelly PW, Corey PN, El-Sohemy A.  Genetic polymorphisms of tumor necrosis factor-alpha modify the association between dietary polyunsaturated fatty acids and fasting HDL-cholesterol and apo A-I concentrations.  Am J Clin Nutr.  2007 Sep; 86(3):768-74.

Samra RA, Wolever TMS, Anderson GH.  Enhanced foor intake regulatory responses after a glucose drink in hyperinsulinemic men.  Intl. J Obes.  2007 Aug;31(8):1222-31.

Grysman A, Carlson T, Wolever TMS.  Effects of sucromalt on postprandial responses in human subjects.  Eur J Clin Nutr.  2007 Aug 22.

Wolever TMS, IP B, Moghaddam E.  Measuring glycaemic responses: duplicate fasting measures of one fasting sample? Br J Nutr. 2006 Nov; 96(5): 799-802.

Moghaddam E, Vogt JA, Wolever TMS.  The effects of fat and protein on glycemic responses in nondiabetic humans vary with waist circumference, fasting plasma insulin, and dietary fiber intake.  J. Nutr. 2006 Oct; 136 (10): 2506-11.

Chui MH, Papanikolau Y, Fontaine-Bisson B, Turcotte J, Wolever TMS, El-Sohemy A, Chiasson JL, Rabasa-Lhoret R, Maheux P, Ryan E, Greenwood CE.  The TNF-alpha-238G> a single-nucleotide polymorphism protects against memory decline in older adults with type 2 diabetes.  Behav Neurosci.  2007 Jun; 121 (3): 619-24.

Wolever, TMS, Yang M, Zeng XY, Atkins F, Brand-Miller J. Food glycemic index, as given in Glycemic Index tables, is a significant determinant of glycemic response elicited by composite breakfast meals. Am J of Clin Nutr. 2006 June; 83(6): 1306-1312.

Wolever TM. Effect of blood sampling schedule and method of calculating the area under the curve on validity and precision of glycaemic index values. Br J Nutr. 2004 Feb;91(2):295-301.

Wolever TMS, Vorster HH, Björk I, Brand-Miller J, Brighenti F, Mann JI, Ramdath DD, Granfeldt Y, Holt S, Perry TL, Venter C, Wu, X. Determination of the glycaemic index of foods: interlaboratory study. Eur J Clin Nutr 2003;57:475-82.

Wolf BW, Wolever TM, Lai CS, Bolognesi C, Radmard R, Maharry KS, Garleb KA, Hertzler SR, Firkins JL. Effects of a beverage containing an enzymatically induced-viscosity dietary fiber, with or without fructose, on the postprandial glycemic response to a high glycemic index food in humans. Eur J Clin Nutr. 2003 Sep;57(9):1120-7.

Wolever TM, Mehling C. Long-term effect of varying the source or amount of dietary carbohydrate on postprandial plasma glucose, insulin, triacylglycerol, and free fatty acid concentrations in subjects with impaired glucose tolerance. Am J Clin Nutr. 2003 Mar;77(3):612-21.

Jenkins DJ, Wolever TM, Taylor RH, Barker H, Fielden H, Baldwin JM, Bowling AC, Newman HC, Jenkins AL, Goff DV. Glycemic index of foods: a physiological basis for carbohydrate exchange. Am J Clin Nutr. 2002 Jul;76(1):264S-5S.

Wolever TM, Mehling C. High-carbohydrate-low-glycaemic index dietary advice improves glucose disposition index in subjects with impaired glucose tolerance. Br J Nutr. 2002 May;87(5):477-87.

Wolever TM, Hamad S, Chiasson JL, Josse RG, Leiter LA, Rodger NW, Ross SA, Ryan EA. Day-to-day consistency in amount and source of carbohydrate associated with improved blood glucose control in type 1 diabetes. J Am Coll Nutr. 1999 Jun;18(3):242-7.

Wolever TM, Chiasson JL, Csima A, Hunt JA, Palmason C, Ross SA, Ryan EA. Variation of postprandial plasma glucose, palatability, and symptoms associated with a standardized mixed test meal versus 75 g oral glucose. Diabetes Care. 1998 Mar;21(3):336-40.

Wolever TM, Bolognesi C. Prediction of glucose and insulin responses of normal subjects after consuming mixed meals varying in energy, protein, fat, carbohydrate and glycemic index. J Nutr. 1996 Nov;126(11):2807-12.

Wolever TM, Jenkins DJ, Vuksan V, Jenkins AL, Wong GS, Josse RG Beneficial effect of low-glycemic index diet in overweight NIDDM subjects. Diabetes Care. 1992 Apr;15(4):562-4.

Wolever TM, Jenkins DJ, Vuksan V, Josse RG, Wong GS, Jenkins AL. Glycemic index of foods in individual subjects. Diabetes Care. 1990 Feb;13(2):126-32.

Wolever TM, Jenkins DJ, Ocana AM, Rao VA, Collier GR. Second-meal effect: low-glycemic-index foods eaten at dinner improve subsequent breakfast glycemic response. Am J Clin Nutr. 1988 Oct;48(4):1041-7.

Jenkins DJ, Wolever TM, Collier GR, Ocana A, Rao AV, Buckley G, Lam Y, Mayer A, Thompson LU. Metabolic effects of a low-glycemic-index diet. Am J Clin Nutr. 1987 Dec;46(6):968-75.

Jenkins DJA, Wolever TMS, Taylor RH, Barker HM, Fielden H, Baldwin JM, Bowling AC, Newman HC, Jenkins AL, Goff DV. Glycemic index of foods: a physiological basis for carbohydrate exchange. Am J Clin Nutr 1981;34:362-366.


Wolever TMS. The glycemic index in the management of obesity.  Endocrinology Rounds 2008;8(2): 1-6.

Merchant AT, Anand SS, Vuksan V, Jacobs R, Davis B, Teo K, Yusuf S. Protein intake is inversely associated with abdominal obesity in a multi-ethnic population. J Nutr. 2005, 135: (5):1196-201.

Wolever TM. Carbohydrate and the regulation of blood glucose and metabolism. Nutr Rev. 2003 May;61(5 Pt 2):S40-8.

Wolever TM. Dietary carbohydrates and insulin action in humans. Br J Nutri. 2000 Mar;83 Suppl 1:S97-102. Review.

Wolever TM. The glycemic index: flogging a dead horse? Diabetes Care. 1997 Mar;20(3):452-6. Review.

Jenkins DJ, Josse RG, Jenkins AL, Wolever TM, Vuksan V. Implications of altering the rate of carbohydrate absorption from the gastrointestinal tract. Clin Invest Med. 1995 Aug;18(4):296-302. Review.

Wolever TM. The glycemic index. World Rev Nutr Diet. 1990;62:120-85. Review.

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