Original Research Effects of Changing the Amount and Source of Dietary Carbohydrates on Symptoms and Dietary Satisfaction Over a 1-Year Period in Subjects with Type 2 Diabetes: Canadian Trial of Carbohydrates in Diabetes (CCD) Thomas M.S. Wolever MD, PhD a,b, *, Jean-Louis Chiasson MD c , Robert G. Josse MD a,b , Lawrence A. Leiter MD a,b , Pierre Maheux MD d , Rémi Rabasa-Lhoret MD e , N. Wilson Rodger MD f , Edmond A. Ryan MD g a Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada b Department of Medicine, St. Michael’s Hospital, Toronto, Ontario, Canada c Research Center (CHUM) Hôtel-Dieu de Montréal, University of Montréal, Montréal, Québec, Canada d Department of Medicine, University of Sherbrooke, Sherbrooke, Québec, Canada e IRCM (Institut de Recherches Cliniques de Montréal), Montréal, Québec, Canada f Department of Medicine, St. Joseph’s Health Centre, Western University, London, Ontario, Canada g Department of Medicine, University of Alberta, Edmonton, Alberta, Canada article info Article history: Received 7 January 2015 Received in revised form 20 July 2016 Accepted 22 August 2016 Keywords: diet dietary satisfaction glycemic index quality of life randomized controlled clinical trial symptoms abstract Objectives: To determine the long-term effects of changing the amount or source of dietary carbohy- drate on quality of life (QOL), symptoms and dietary satisfaction in people with type 2 diabetes. Methods: Subjects with diabetes treated by diet alone (n=162) were randomly assigned to high-carbohydrate/ high-glycemic-index (HGI) diets; high-carbohydrate/low-glycemic-index (LGI) diets; or lower-carbohydrate/ high-monounsaturated-fat (LC) diets for 1 year. We measured QOL at baseline and at study’s end, and we measured symptoms and dietary satisfaction quarterly. Results: The HGI, LGI and LC diets contained, respectively, 47±1, 52±1 and 40±1% energy carbohydrate; 30±1, 27±1 and 40±1% fat with GI 64±0.4, 55±0.4 and 59±0.4. Significantly more participants reported increased flatulence on LGI than on LC and HGI diets at 3 months (41%, 19%, 14%; p<0.05), but not at 12 months (29%, 17%, 17%; ns). Abdominal distension was more severe (46% vs. 14%, 19%; p<0.05), and headache less severe (8% vs. 22%, 23%; p<0.05) on LGI than on both other diets. Increased appetite was more severe on LC (33%) than on HGI diets (14%, p<0.05). Joint/limb pains were less severe on LGI (16%) than HGI (28%) diets. LC elicited more severe gloomy thoughts (23%) than LGI (4%; p<0.05) but greater dietary-satisfaction (70%; p<0.05) than LGI (40%) and HGI (48%) diets. For all diets, glycated hemoglobin (A1C) levels increased less in those who gained less weight, had less increased appetite and were more satisfied with the enjoyment obtained from eating. Conclusions: Each diet elicited increased severity of 1 or more symptoms than the other diets. Although overall dietary satisfaction was greater on the 40% carbohydrate diet than on the 50% carbohydrate diet, the LGI diet was no less satisfying than the HGI diet. Changes in appetite and dietary satisfaction may influence body weight and glycemic control, or vice-versa. © 2016 Canadian Diabetes Association. Mots clés : régime alimentaire satisfaction alimentaire indice glycémique qualité de vie essai clinique à répartition aléatoire symptômes résumé Objectifs : Déterminer les effets à long terme de la modification de la quantité ou de la source des glucides alimentaires sur la qualité de vie (QdV), les symptômes et la satisfaction alimentaire chez les personnes atteintes du diabète de type 2. Méthodes : Les sujets diabétiques traités par le régime alimentaire seul (n=162) ont été répartis de manière aléatoire entre les régimes à haute teneur en glucides/à indice glycémique élevé (IGÉ), les régimes à haute teneur en glucides/à indice glycémique faible (IGF) ou les régimes à plus faible teneur en glucides/à forte teneur en gras mono-insaturés (FTG) durant 1 année. Nous avons mesuré la QdV au début et à la fin de l’étude, et mesuré les symptômes et la satisfaction alimentaire tous les 3 mois. * Address for correspondence: Thomas M.S. Wolever, MD, PhD, Department of Nutritional Sciences, University of Toronto, Toronto, Ontario M5S 3E2, Canada. E-mail address: thomas.wolever@utoronto.ca Can J Diabetes xxx (2016) 1–13 Contents lists available at ScienceDirect Canadian Journal of Diabetes journal homepage: www.canadianjournalofdiabetes.com 1499-2671 © 2016 Canadian Diabetes Association. http://dx.doi.org/10.1016/j.jcjd.2016.08.223 ARTICLE IN PRESS