Investigations into the Effects of Turmeric, Cinnamon and Green Tea on Glycaemic Control and Liver Enzymes Wickenberg, Jennie 2015 Link to publication Citation for published version (APA): Wickenberg, J. (2015). Investigations into the Effects of Turmeric, Cinnamon and Green Tea on Glycaemic Control and Liver Enzymes. Department of Clinical Sciences, Lund University. Total number of authors: 1 General rights Unless other specific re-use rights are stated the following general rights apply: Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal Read more about Creative commons licenses: https://creativecommons.org/licenses/ Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. LUND UNIVERSITY PO Box 117 221 00 Lund +46 46-222 00 00 Printed by Media-Tryck, Lund University 2015 JENNIE WICKENBERG JENNIE InvestigationsTurmeric, into the EffectsTeaon CinnamonGlycaemic of Control and GreenLiverand Enzymes Investigations into the Effects of Turmeric, Cinnamon and Green Tea on Glycaemic Control and Liver Enzymes JENNIE WICKENBERG DEPARTMENT OF CLINICAL SCIENCES, MALMÖ | LUND UNIVERSITY Experimental Cardiovascular Research Unit Department of Clinical Sciences, Malmö Lund University, Faculty of Medicine Doctoral Dissertation Series 2015:17 ISBN 978-91-7619-097-5 ISSN 1652-8220 Investigations into the Effects of Turmeric, Cinnamon and Green Tea on Glycaemic Control and Liver Enzymes Jennie Wickenberg Academic thesis which, by due permission of the Faculty of Medicine at Lund University, will be publicly defended on Friday February 20th in lecture theatre Lilla Aulan at Jan Waldenströms gata 5, the Department of Clinical Sciences, Skåne University Hospital, Malmö, Sweden. Faculty opponent Associate Professor Ulf Risérus Uppsala University Hospital, University of Uppsala, Sweden Organization Document name DOCTORAL DISSERTATION LUND UNIVERSITY Department of Clinical Sciences, Medicine Date of issue Skåne University Hospital Malmö, Lund University, February 20, 2015 Sweden Author Sponsoring organization Jennie Wickenberg Title and subtitle Investigations into the Effects of Turmeric, Cinnamon and Green Tea on Glycaemic Con- trol and Liver Enzymes Abstract Lifestyle changes such as caloric over-consumption and decreased physical activity are causing overweight and obesity, leading to an epidemic increase in type 2 diabetes mellitus (T2DM). Overweight, cardiovascular disease and diabetes are closely linked, and cardiovascular disease is the most important cause of morbidity and mortality among patients with T2DM. Identifying food that can reduce blood glucose and insulin, and increase satiety can help in the prevention and reduction of diabetes and overweight. The aim of this research was to gain further knowledge of the role of nutritional interventions, LQSDUWLFXODUWR¿QGIXQFWLRQDOIRRGVWKDWUHGXFHSRVWSUDQGLDOEORRGJOXFRVHDQGLQVXOLQOHYHOV in order to improve glycaemic control. Satiety was evaluated in one of the studies to gain an understanding of food factors affecting postprandial satiety. The ingestion of 6 g turmeric increased postprandial serum insulin levels, but did not seem to affect plasma glucose levels or glycaemic index (GI) in healthy subjects. Thus, turmeric may have an effect on insulin secretion. Green tea showed no glucose- or insulin-lowering effects. However, increased satiety and a feeling of fullness were reported by the participants after drinking green WHD7KHLQJHVWLRQRIJ&H\ORQFLQQDPRQKDGQRVLJQL¿FDQWHIIHFWRQJOXFRVHOHYHOLQVXOLQ response, GI or insulinaemic index. The ingestion of 6 g Cassia cinnamon twice a day for 12 ZHHNVKDGQRVLJQL¿FDQWHIIHFWRQLQVXOLQVHQVLWLYLW\+E$FIDVWLQJJOXFRVHRUERG\PDVVLQGH[ 1RVLJQL¿FDQWFKDQJHVZHUHVHHQLQOLSLGVRUOLYHUHQ]\PHV Key words: Green tea, Cinnamon, Glycaemic control, insulin, liver enzymes &ODVVL¿FDWLRQV\VWHPDQGRULQGH[WHUPV LIDQ\ Supplementary bibliographical information Language: English [email protected] ISSN and key title ISBN 1652-8220, Lund University, Faculty of Medicine Doctoral Dissertation Series 2015:17 978-91-7619-097-5 Recipient’s notes Number of pages 110 Price 6HFXULW\FODVVL¿FDWLRQ I, the undersigned, being the copyright owner of the abstract of the above-mentioned dissertation, hereby grant to all reference sources permission to publish and disseminate the abstract of the above-mentioned dissertation. Signature Date January 20, 2015 Investigations into the Effects of Turmeric, Cinnamon and Green Tea on Glycaemic Control and Liver Enzymes Jennie Wickenberg Department of Clinical Sciences in Malmö Faculty of Medicine, Lund University, Sweden Photographs by Johan Wickenberg Copyright Jennie Wickenberg 2015 Faculty of Medicine Department of Clinical Sciences Lund University, Faculty of Medicine Doctoral Dissertation Series 2015:17 ISSN 1652-8220 ISBN 978-91-7619-097-5 Printed in Sweden by Media-Tryck, Lund University, Lund 2015 To my beloved family Contents Abstract 9 Abbreviations 10 List of Publications 12 Introduction 13 Diabetes 14 Definition and diagnosis 14 Prevalence of diabetes type 2 15 Risk factors 15 Complications 17 The Metabolic Syndrome 18 Definition and diagnosis 18 Insulin Sensitivity 19 Insulin resistance 19 Measurement of insulin sensitivity 21 Satiety and satiation 22 Functional Foods 25 Background 25 Cinnamon 26 Turmeric 28 Green tea 29 The Present Investigation 31 Aims of the Study 31 Ethical Committee Approval 31 Overview 32 Subjects 32 The Malmö preventive project 32 Methods 33 Anthropometric measurements 34 Substances studied 35 Satiety 36 Laboratory analyses 36 Insulin sensitivity 37 Statistical analyses 37 Results 39 The Effects ofTurmeric 39 Postprandial plasma glucose response to turmeric 39 The effects of turmeric on postprandial insulin response 40 The effects of turmeric on GII 41 The Effects of Green Tea 42 Postprandial plasma glucose response to green tea 42 Postprandial insulin response to green tea 42 The effect of green tea on GI 43 The effect of green tea on various aspects of satiety 45 The Effects of Ceylon cinnamon 46 Postprandial plasma glucose response to Ceylon cinnamon 46 Postprandial insulin response to Ceylon cinnamon 47 The effects of Ceylon cinnamon on GI and GII 47 The Effects of Cassia cinnamon 48 Anthropometric measurements 48 Effects on glycaemic outcomes, lipids and liver enzymes 48 Effect of Cassia cinnamon on insulin sensitivity 50 Discussion 51 Results Obtained with Turmeric 51 Results Obtained with Green Tea 52 Results Obtained with Cinnamon 54 General Limitations 56 Summary in Swedish 57 Populärvetenskaplig Sammanfattning 57 Gurkmeja 58 Grönt te 58 Kanel 59 Acknowledgements 63 References 65 Abstract Lifestyle changes such as caloric over-consumption and decreased physical activity are causing overweight and obesity, leading to an epidemic increase in type 2 dia- betes mellitus (T2DM). Overweight, cardiovascular disease and diabetes are closely linked, and cardio-vascular disease is the most important cause of morbidity and mortality among patients with T2DM. Identifying food that can reduce blood glu- cose and insulin, and increase satiety can help in the prevention and reduction of diabetes and overweight. The aim of this research was to gain further knowledge of the role of nutritional interventions, in particular, to find functional foods that reduce postprandial blood glucose and insulin levels in order to improve glycaemic control. One of the studies was to gain an understanding of food factors affecting postprandial satiety. The ingestion of 6 g turmeric increased postprandial serum insulin levels, but did not seem to affect plasma glucose levels or glycaemic index (GI) in healthy sub- jects. Thus, turmeric may have an effect on insulin secretion. Green tea showed no glucose- or insulin-lowering effects. However, increased satiety and a feeling of full- ness were reported by the participants after drinking green tea. The ingestion of 6 g Ceylon cinnamon had no significant effect on glucose level, insulin response, GI or insulinaemic index. The ingestion of 6 g Cassia cinnamon twice a day for 12 weeks had no significant effect on insulin sensitivity, HbA1c, fasting glucose or body mass index. No significant changes were seen in lipids or liver enzymes. 9 Abbreviations ACE angiotensin converting enzyme ADA American Diabetes Association ALAT alanine aminotransferase ALP alkaline phosphatase ASAT aspartate aminotransferase ATP adenosine triphosphate AUC area under the curve BMI body mass index EC epicatechin ECG epicatechin gallate EGC epigallocatechin EGCG epigallocatechin gallate GI glycaemic index GII insulinaemic index GT gamma glutamyl transferase HbA1c haemoglobin A1c HDL high-density lipoprotein HOMA-IR homeostatic model assessment of insulin resistance IFG impaired fasting glucose IGT impaired glucose tolerance IL-6 interleukin-6 IR-E insulin receptor- E IRS insulin receptor substrate ISI insulin sensitivity index LDL low-density lipoprotein mDNA