2057.pdf

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Scientific Opinion on the substantiation of health claims related to coffee, including chlorogenic acids from coffee, and protection of DNA, proteins and lipids from oxidative damage (ID 1099, 3152, 4301), maintenance of normal blood glucose concentrations (ID 1100, 1962), and contribution to the maintenance or achievement of a normal body weight (ID 2031, 4326) pursuant to Article 13(1) of Regulation (EC) No 1924/2006[sup]1[/sup] EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA)2, 3 European Food Safety Authority (EFSA), Parma, Italy
Słowa kluczowe: Coffee   blood glucose   health claims   oxidative damage   weight management  
ID:    3152      4301      1099      1100      4326      1962      2031  
Produkty: Kofeina   Antyoksydanty z kawy   Kawa   Kwasy chlorogenowe z kawy  

1. Charakterystyka żywności / składnika

The foods/food constituents that are the subjects of the health claims are coffee, Coffea Arabica L., chlorogenic acids from coffee, and antioxidants in coffee.
Coffee contains a wide range of “bioactive” compounds including caffeine and other purine derivatives, polyphenolic compounds such as chlorogenic acid derivatives and its degradation product caffeic acid, and specific diterpenes such as kahweol and cafestol. No information is provided on the concentration of such compounds in coffee, but this will likely depend on the coffee variety, on the roasting of the beans and on the brewing process, such as the use of coffee filters. Also, no specifications were provided on the compounds or molecules generically referred to as “antioxidants in coffee”.
The Panel notes that chlorogenic acid from coffee has been specified as the “active” food constituent responsible for the claimed effects considered in this opinion. Chlorogenic acids from coffee are well defined compounds which can be measured in foods by established methods.
The Panel considers that whereas the food/food constituents, coffee and antioxidants in coffee, are not sufficiently characterised in relation to the claimed effects evaluated in this opinion, the food constituent, chlorogenic acids from coffee, is sufficiently characterised.

2. Znaczenie oświadczenia dla zdrowia człowieka


2.1. Ochrona DNA, białek i lipidów przed uszkodzeniem oksydacyjnym (ID 1099, 3152, 4301)

The claimed effects are “protection of body tissues, lipids, cells and DNA from oxidative damage”, “oxidative stress reduction” and “coffee naturally contains antioxidants that may support the body's natural cell defences”. The Panel assumes that the target population is the general population.
Reactive oxygen species (ROS) including several kinds of radicals are generated in biochemical processes (e.g. respiratory chain) and as a consequence of exposure to exogenous factors (e.g. radiation and pollutants). These reactive intermediates damage molecules such as DNA, proteins
and lipids if they are not intercepted by the antioxidant network which includes radical scavengers like antioxidant nutrients.
The Panel considers that protection of DNA, proteins and lipids from oxidative damage may be a beneficial physiological effect.

2.2. Utrzymanie prawidłowego stężenia glukozy we krwi (ID 1100, 1962)

The claimed effect is “glucose homeostasis”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel assumes that the claimed effect refers to the long-term maintenance of normal blood glucose concentrations.
The Panel considers that long-term maintenance of normal blood glucose concentrations is a beneficial physiological effect.

2.3. Udział w utrzymaniu lub osiągnięciu prawidłowej masy ciała (ID 2031, 4326)

The claimed effects are “weight loss and weight control in overweight adults/reduces glucose absorption from gut” and “promotes weight-loss and weight-control in overweight healthy adults by reducing glucose uptake in the gastrointestinal system/absorbance from the gut (by regulating glucose homeostasis in the liver, thus promoting the use as fat as a source of energy in the body)”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel assumes that the claimed effects refer to body weight control.
Weight management can be interpreted as the contribution to maintenance of a normal body weight. In this context, weight loss in overweight subjects without achieving a normal body weight is considered to be a beneficial physiological effect.
The Panel considers that contribution to the maintenance or achievement of a normal body weight is a beneficial physiological effect.

3. Naukowe uzasadnienia wpływu na zdrowie człowieka


3.1. Ochrona DNA, białek i lipidów przed uszkodzeniem oksydacyjnym (ID 1099, 3152, 4301)

Some of the references provided in the consolidated list reported on the association between coffee drinking and disease risk (e.g. hepatocellular carcinoma, liver cirrhosis, breast cancer, colon cancer, and inflammatory and cardiovascular disease) in observational (cohort) studies. Other references were general reviews on claim substantiation, on biomarkers for chronic disease risk, on the chemistry and absorption of chlorogenic acids and other polyphenols from coffee, and on the effects of coffee drinking on liver enzyme activity (a marker of liver damage), and on endothelial and vascular function. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
Some experimental, and generally small-scale, human intervention studies on the effects of coffee consumption, or of individual compounds present in coffee, on markers of antioxidant status (e.g. antioxidant activity/capacity/potential of plasma (Natella et al., 2002)), on the induction of antioxidant enzymes such as super-oxide dismutase (SOD) or glutathione S-transferases (GSTA and
GSTP) and/or on plasma concentrations of glutathione (GSH) (Bichler et al., 2007; Esposito et al., 2003; Grubben et al., 2000; Mursu et al., 2005; Steinkellner et al., 2005), on the formation of malondialdehyde (MDA), on thiobarbituric acid reactive substances (TBARS), and/or on LDL oxidation lag time (Mursu et al., 2005; Yukawa et al., 2004) were provided. The Panel notes that measurements of the total antioxidant activity/potential of plasma are not considered as markers of oxidative damage, and that the formation of TBARS or of MDA assessed by colorimetric assays, as well as the resistance of LDL to oxidation, are not suitable markers to assess lipid peroxidation (Dalle-Donne et al., 2006; Dragsted, 2008; Griffiths et al., 2002; Knasmuller et al., 2008; Mayne, 2003). Also two small intervention studies on the effects of coffee consumption on DNA damage measured ex vivo in lymphocytes using single cell gel electrophoresis (Comet assay) after incubation with restriction enzymes and treatment with H2O2 or a heterocyclic compound (Bichler et al., 2007), and on benzo[a]pyrene diolepoxide (BPDE) induced DNA-migration using the Comet assay (Steinkellner et al., 2005), were presented. The Panel notes that these measurements do not provide information about oxidative damage to DNA in vivo (Dusinska and Collins, 2008). The Panel also notes that coffee has not been sufficiently characterised in these studies in relation to the claimed effect, and that its content of chlorogenic acids has not been reported. The Panel considers that no conclusions can be drawn from these studies for the scientific substantiation of the claimed effect.
In a multiple-dose supplementation trial, 43 healthy non-smoking men consumed daily either no coffee, 3 cups (450 mL) or 6 cups (900 mL) of filtered coffee (7–8 g of grounds per 150 mL cup) for three weeks. In vivo LDL oxidation using conjugated dienes, plasma hydroxy fatty acids, activity of antioxidant enzymes, and plasma F2-isoprostanes were assessed (Mursu et al., 2005). The Panel notes that coffee has not been sufficiently characterised in this study in relation to the claimed effect, and that its content of chlorogenic acids has not been reported. The Panel considers that no conclusions can be drawn from this study for the scientific substantiation of the claimed effect.
Data from in vitro studies on the effect of caffeic acid on LDL resistance to oxidation (lag time), and on glutathione (GSH) depletion (Nardini et al., 1995; 1997; Richelle et al., 2001), and studies on the chemopreventive effects of chlorogenic acids in human cancer cell lines, on transcription factors and biomarkers of cell proliferation (Bandyopadhyay et al., 2004; Feng et al., 2005), and on the effects of kahweol and cafestol on induced DNA damage in cultured NIH3T3 cells (Lee and Jeong, 2007), were submitted. The Panel considers that evidence provided in in vitro studies is not sufficient to predict the occurrence of an effect of coffee on protection of DNA, lipids or proteins from oxidative damage in vivo in humans.
The Panel concludes that a cause and effect relationship has not been established between the consumption of chlorogenic acids from coffee and protection of DNA, lipids or proteins from oxidative damage.

3.2. Utrzymanie prawidłowego stężenia glukozy we krwi (ID 1100, 1962)

Some of the references provided for the substantiation of the claim reported on the association between coffee drinking and disease risk (e.g. type II diabetes, gestational diabetes, metabolic disease, cardiovascular disease) in observational (cohort) studies, and on the effects of chlorogenic acids on various aspects of glucose metabolism (enzymes and transporter proteins). Other references included reviews on the dietary sources of chlorogenic acids, and on magnesium supplementation in diabetes. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
Five references reported on human intervention studies which investigated the effects of coffee consumption on either post-prandial glycaemic and insulinaemic responses (Battram et al., 2006; Feinberg et al., 1968; Johnston et al., 2003; Keijzers et al., 2002), or on plasma C-peptide
concentrations (Wu et al., 2005). The Panel considers that no conclusions can be drawn from these outcome measures in relation to the long-term maintenance of normal blood glucose concentrations.
Two references reported on human intervention studies which addressed the effects of coffee consumption during two to four weeks on fasting glucose and insulin concentrations (Naismith et al., 1970; van Dam et al., 2004). Another reference reported on a cross-sectional study which investigated the association between coffee intake and glucose tolerance and insulin secretion during an oral glucose tolerance test (Bidel et al., 2006). In all of these studies, coffee was not sufficiently characterised in relation to the claimed effect, and outcome measures were not appropriate to assess the long-term maintenance of normal blood glucose concentrations. The Panel considers that no conclusions can be drawn from these studies for the scientific substantiation of the claimed effect.
The Panel concludes that a cause and effect relationship has not been established between the consumption of chlorogenic acids from coffee and maintenance of normal blood glucose concentrations.

3.3. Udział w utrzymaniu lub osiągnięciu prawidłowej masy ciała (ID 2031, 4326)

A number of references on the bioavailability of chlorogenic acids, on the effects of coffee and chlorogenic acids on blood glucose control, and on the effects of chlorogenic acids in animal and in vitro models with respect to mutagenicity, antioxidant capacity and inhibition of hepatic glucose-6-phosphatase have been provided. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
A randomised, controlled trial investigated the effects of an instant coffee containing a green coffee extract (200 mg of extract per 2200 mg of coffee) with a high content of chlorogenic acids (i.e. 90-100 mg of chlorogenic acids per 200 mg of green coffee extract with equal amounts of the three isomers 5-, 4-, and 3-caffeoylquinic acid) and <2 % caffeine with no cafestol or kahweol vs. regular decaffeinated instant coffee containing 30-40 mg of chlorogenic acid per g of coffee on body weight in 30 overweight adults (Thom, 2007). Participants selected were overweight, non-smokers, and not taking medication on a regular basis for the treatment of chronic diseases, and were asked to maintain their usual diet and physical activity or exercise programmes. Subjects consumed 11 g of the test coffee per day (n=15) or 11 g of the control coffee per day (n=15), in both cases as black coffee, for 12 weeks, and were followed up for one and three months after the end of the study. The Panel notes the small sample size of the study, and that the background diet and physical activity at baseline, along with changes during the study, were not assessed and/or reported, for which reason it is unclear whether intervention and control groups were comparable for these variables. The Panel notes the important methodological limitations of the study and considers that no conclusions can be drawn from this study for the scientific substantiation of the claimed effect.
Another randomised, placebo-controlled human intervention study on the effects of a green coffee extract (200 mg of extract per capsule) containing chlorogenic acids (i.e. 90-100 mg per capsule with equal amounts of the three isomers 5-, 4-, and 3-caffeoylquinic acid) and <2 % caffeine with no cafestol and kahweol vs. placebo (maltodextrin) on body weight in overweight and obese subjects (males and females aged 19 to 75 years) was provided (Dellalibera et al., 2006). Participants were randomised to consume two capsules daily of the green coffee extract (n=30) or placebo (n=20) with the main meal for 60 days in the context of a “mildly hypocaloric diet”. The Panel notes that, although the authors reported that the intervention and placebo groups were “homogeneous with respect to body weight and fat-free mass to fat mass ratio”, the baseline characteristics of participants in both groups were not provided, and that whether these groups were comparable for other variables (e.g. age and sex distribution) was not reported. The Panel also notes that the background diet and physical activity at baseline and during the intervention were not reported, and that no details were given with
respect to the “mildly hypocaloric diet” prescribed during the study, nor on whether (and how) compliance with dietary advice was checked. The Panel notes the important methodological limitations of the study and considers that no conclusions can be drawn from this study for the scientific substantiation of the claimed effect.
The Panel concludes that a cause and effect relationship has not been established between the consumption of chlorogenic acids from coffee and contribution to the maintenance or achievement of a normal body weight.

Wnioski

On the basis of the data presented, the Panel concludes that:
The food/food constituents, coffee and antioxidants in coffee, which are the subjects of the health claims, are not sufficiently characterised in relation to the claimed effects evaluated in this opinion, whereas chlorogenic acids from coffee are sufficiently characterised.
Protection of DNA, proteins and lipids from oxidative damage (ID 1099, 3152, 4301)
The claimed effects are “protection of body tissues, lipids, cells and DNA from oxidative damage”, “oxidative stress reduction” and “coffee naturally contains antioxidants that may support the body’s natural cell defences”. The target population is assumed to be the general population. Protection of DNA, proteins and lipids from oxidative damage may be a beneficial physiological effect.
A cause and effect relationship has not been established between the consumption of chlorogenic acids from coffee and protection of DNA, lipids or proteins from oxidative damage.
Maintenance of normal blood glucose concentrations (ID 1100, 1962)
The claimed effect is “glucose homeostasis”. The target population is assumed to be the general population. Long-term maintenance of normal blood glucose concentrations is a beneficial physiological effect.
A cause and effect relationship has not been established between the consumption of chlorogenic acids from coffee and maintenance of normal blood glucose concentrations.
Contribution to the maintenance or achievement of a normal body weight (ID 2031, 4326)
The claimed effects are “weight loss and weight control in overweight adults/reduces glucose absorption from gut” and “promotes weight-loss and weight-control in overweight healthy adults by reducing glucose uptake in the gastrointestinal system/absorbance from the gut (by regulating glucose homeostasis in the liver, thus promoting the use as fat as a source of energy in the body)”. The target population is assumed to be the general population. Contribution to the maintenance or achievement of a normal body weight is a beneficial physiological effect.
A cause and effect relationship has not been established between the consumption of chlorogenic acids from coffee and contribution to the maintenance or achievement of a normal body weight.