1 Coffee: the new health food against type 2 diabetes? Claire Prunel-ENSAIA student Update 07/27/2004

2 Diabetes type 2 affects over one million in UK in early Is it worth drinking large amount of coffee to reduce development of type 2 diabetes? = ?

3 The protective effect of coffee consumption A Swedish study : a 18 year-follow-up-study (1981 to 1999) -Reliable study : lot of factors taking into account -Sort of coffee? A Dutch study (Nov 2002) -Conclusion : drink at least 7 cups of coffee a day lower risk of type 2 DM compared with less than 2 cups of coffee a day -Type of coffee? paper filtered coffee -They look at the lifestyle habits A Japanese study -Same results that the Dutch study -Caffeine is known to increase lipolysis and to enhance insulin secretion

4 The protective effect of coffee consumption The Finnish study published in March 2004: a 12-year follow-up study -Data combined from 3 previous studies -Result: people who drank at least 3-4 cups a day reduce by 30% the risk of development of type 2 diabetes -Reliable study: they looked at a variety of lifestyle factors (low physical activity, smoking, alcohol consumption, socioeconomic status, education…)

5 No conclusive results about the protective effect of coffee One study attempted to replicate the Dutch finding among the Pima Indians (2002) -Result: No relationship between coffee consumption and type 2 diabetes -Coffee consumption was associated with lower socio economic status and less healthy behaviours The Finnish study -They used to consume boiled coffee -Unhealthy lifestyle factors as diet weren’t take into account

6 Conclusion: Researchers say it is too soon to recommend people increase their daily dose of coffee.

7 Composition of roasted coffee (according to variety) and of instant coffee (% of dry basis)

8 Harmful components

9 Pentacyclic diterpenes need to be eliminated Appear when you add hot water on coffee beans : 16-O- methylcafestol (Robusta coffee), cafestol (Arabica coffee), kahweol (Arabica) No present in any other foods Largely esterified with fatty acids, no present in free form Negative effect  increase cholesterol levels in affecting the liver’s metabolism of cholesterol and increase plasma triacylglycerol => The main risk to contract diabetes is a high level of triglycerides

10 Pentacyclic diterpenes need to be eliminated The absolute amount depend on the type of preparation -Lowest amount in filtered coffee 0.3% of the initial quantity -Intermediate amount in espresso 2.5% of the initial quantity -One cup of unfiltered coffee = 3mg = enough to increase cholesterol level => Solution: TO FILTER COFFEE TO REMOVE THE TERPENES

11 Beneficial components of coffee: Antioxidants Caffeine Minerals

12 Antioxidants naturally present -Offset negative effects of caffeine Chlorogenic and caffeic acids -Antioxidant activity and delay LDL oxidation (In contact with arteries cells, LDL are oxidized unloading cholesterol. It induces formation of lesions full of cholesterol in arteries that increases risk of CHD). -Chlorogenic acid: -increases glucose tolerance -decreases some plasma and liver lipids

13 Antioxidants Quinides of roasted coffee: a degradation product of chlorogenic acids -Enhance insulin action by increase whole body glucose disposal independently of muscles -Experiment in rats => to confirm Tocopherols Phenols and polyphenols

14 Minerals Offset negative effects of caffeine Magnesium -Affect blood sugar regulation -Lower insulin resistance in skeletal muscle and increases insulin secretion -Insulin stimulates the transport of Mg from extracellular to intracellular compartment Potassium -Potassium is depleted by low blood sugar  lack of K -Potassium deficiency promote hypoglycaemia Calcium

15 Caffeine -Activates energy metabolism -Increases metabolic rate and thermogenesis of brown adipose tissue (in mice) -Improves glucose tolerance and reduce fasting plasma concentration of insulin because it upregulates expression of UCP (Uncoupling Protein)* -Caffeine may overcome the energy imbalance accompanied by unfavourable lifestyle and improve glucose homeostasis.

16 * Differences between white and brown adipose tissue -Structure and functions are different -White adipose tissue is the fat tissue providing insulation and by storing triglyceride it appears as energy depot -Brown adipose tissue (BAT) is unique in mammals and rodents. It is a heat-producing tissue where energy is dispersed as heat instead of being used in ATP synthesis through an oxidation of fuels via UCP. In fact, BAT contains mitochondria expressing a unique protein called UCP, found as a main factor of development of obesity.

17 References 1- Saremi A, Tulloch-Reid M, Knowler WC : Coffee consumption and the incidence of type 2 diabetes. DIABETES CARE 26 (7): , JUL Kurzrock T, Speer K : Diterpenes and diterpene esters in coffee. FOOD REVIEWS INTERNATIONAL 17 (4): , Daniel S W Tan : Coffee consumption and risk of type 2 diabetes mellitus. THE LANCET Volume 361, Issue 9358, Page 702, FEB 2003Volume 361, Issue A. Rosengren, A. Dotevall, L. Wilhelmsen, D. Thelle & S. Johansson: Coffee and incidence of diabetes in Swedish women: a prospective 18-year follow-up study. JOURNAL OF INTERNAL MEDICINE Vol 255 Issue 1 Page 89, JAN Urgert R, Schulz AG, Katan MB. : Effects of cafestol and kahweol from coffee grounds on serum lipids and serum liver enzymes in humans. AM J CLIN NUTRI. 61(1):149-54, JAN De Sotillo DVR, Hadley M.: Chlorogenic acid modifies plasma and liver concentrations of: cholesterol, triacylglycerol, and minerals in (fa/fa) Zucker rats. JOURNAL OF NUTRITIONAL BIOCHEMISTRY 13 (12): , DEC Shearer J, Farah A, de Paulis T, Bracy DP, Pencek RR, Graham TE, Wasserman DH : Quinides of roasted coffee enhance insulin action in conscious rats. JOURNAL OF NUTRITION 133 (11): , NOV 2003

18 References 8- Jaakko Tuomilehto: Coffee Consumption and risk of Type 2 diabetes mellitus among middle aged and Finnish men and women. JAMA 291: , JAN Farah S.L. Thong, Wim Derave, Bente Kiens: Caffeine-Induced Impairment of Insulin Action but Not Insulin Signaling in Human Skeletal Muscle Is Reduced by Exercise. Diabetes 51: , Jerry L. Nadler: Diabetes and Magnesium: The Emerging Role of Oral Magnesium Supplementation. The Magnesium Report, 2000 Web sites: http:// http:// http://