ID 2375 - Kofeina

PL: Kofeina
EN: Caffeine
Pdf: caffeine

Oświadczenie (4)

Oświadczenie (2)

1. Charakterystyka żywności / składnika

The foods/food constituents that are the subject of the health claims are Coffea arabica L. (coffee) and other Coffea spp., Paullinia cupana Kunth (guarana) and caffeine.
Caffeine is a natural compound present in coffee beans and tea leaves. Other sources include the kola nut, yerba mate, guarana berries and Yaupon Holly. Caffeine is a well characterised substance which can be measured by established methods.
The food/food constituent which is the subject of ID 1101 is “Coffea arabica L. and other spp”. Coffee contains a wide range of compounds including caffeine and other purine derivatives, polyphenolic compounds such as the degradation product caffeic acid, and specific diterpenes such as kahweol and cafestol. No information was provided on the concentration of such compounds in coffee, but these compounds will likely depend on the coffee variety, on the roasting of the beans and, in relation to human consumption, on the brewing process, such as the use of coffee filters. The Panel notes that “caffeine” has been specified as the “active” food constituent that is responsible for the claimed effects considered in this opinion, but the Panel also notes that coffee contains a wide and variable range of compounds, including caffeine.
The food constituents which are the subjects of IDs 2063, 2103 and 2375 are “guarana”, “Paullinia cupana (Common Name: guarana)” and “guarana seed; (Paulina cupana fruit)”. The varieties Paullinia cupana Kunth and Paullinia cupana var. sorbilis (Mart.) Ducke are native to the Amazon basin. Guarana is derived from both wild and cultivated plants. The seeds typically contain: caffeine 2.5-5 %, tannins 16 %, saponins, theophylline and theobromine (small quantities) (Carlini, 2003; Houghton, 1995; Scholey and Haskell, 2008). The Panel notes that “caffeine” has been specified as the “active” food constituent which is responsible for the claimed effects considered in this opinion, but the Panel also notes that guarana contains a wide and variable range of compounds, including caffeine.
The Panel considers that, whereas the foods/food constituents Coffea arabica L. and Paullinia cupana Kunth are not sufficiently characterised in relation to the claimed effects evaluated in this opinion, the food constituent caffeine is sufficiently characterised.

2.4. Zwiększenie uwagi (ID 736, 1485, 1491, 2375)

The claimed effects are “cognitive and mental performance”, “mental performance (where mental performance stands for those aspects of brain and nerve functions which determine aspects like concentration, learning, memory and reasoning, as well as resistance to stress)”, “mental performance and cognitive function (enhances mental alertness during intense muscular activity)”, and “invigoration of 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 attention, which means the ability to concentrate while processing information. There are two broad categories
of attention. Selective attention is the ability to concentrate on one task or source of information to the exclusion of others. Sustained attention (vigilance) is the ability to concentrate over a long period of time. Attention is a well defined construct which can be measured by validated psychometric tests.
The Panel considers that increased attention is a beneficial physiological effect.

3.4. Zwiększenie uwagi (ID 736, 1485, 1491, 2375)

A number of the references provided addressed endpoints other than the claimed effects, including mood, cognitive domains other than attention, lipids or carbohydrate metabolism, metabolic rate, physical performance and cardiovascular endpoints, or investigated substances other than caffeine, caffeine in combination with other substances, the effect of caffeine withdrawal rather than the effect of caffeine on subjects under normal conditions of use, or the effect of caffeine in patients with impaired adrenaline responses. A meta-analysis (Riby, 2004) addressed to glucose, and a systematic review (Hoyland et al., 2008) reported on macronutrients but not caffeine, which is the subject of the claim. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claim.
Two double-blind, placebo-controlled intervention trials assessed the effect of a commercial standardised guarana extract (containing approximately 12 % caffeine) on measures of attention (Haskell et al., 2007; Kennedy et al., 2004). The Panel notes that the placebo (capsule containing no guarana extract) used in these two studies did not control for substances other than caffeine. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claim.
One study (Brice and Smith, 2002) investigated the effects of caffeine on performance in three attention tests (focused attention task, categoric search task, 5-choice serial RT). Results for the focused attention task were not reported, and although it was stated that measures of RT and accuracy were obtained for the categoric search task, these results were also not reported. The 5-choice serial RT test was administered for too short a period (3 minutes) to adequately assess sustained attention. Another study (Loke, 1990) examined the effects of caffeine on performance in a symbol cancellation task, but did not report the main effects of the intervention. Haskell et al. (2005) observed the effects of caffeine on performance in a rapid visual information processing test and a digit vigilance reaction time test, in both habitual caffeine consumers and non-consumers. Primary analyses of the effects of caffeine on rapid visual information processing were not reported. No description of the digit vigilance reaction time was provided, and whether this is a validated test of sustained attention cannot be determined. The Panel considers that no conclusions can be drawn from these studies for the scientific substantiation of the claim.
A total of 22 randomised, double-blind, placebo-controlled intervention studies assessed the effects of caffeine on attention. The studies differed with respect to their design (cross-over, parallel), their sample size (11 to 120 subjects), the baseline characteristics of participants (age range 18-72 years; usual coffee consumption from 0 to 7 cups/day), the doses of caffeine administered (range 12.5 mg to 500 mg in drinks/capsules), and the time between caffeine administration and attention testing (range 20 min to 8 hours). The majority of studies used cross-over designs with relatively small sample sizes (15-25 subjects), involved young regular caffeine consumers (males and females, 18-30 years) who were on caffeine withdrawal for at least 12 hours, and administered caffeine doses ranging from 100 mg to 300 mg in a single dose, 45-90 min before attention testing.
Ten studies examined the effect of caffeine on selective attention by means of a range of psychometric tasks (e.g. visual selective search task, colour selection task, spatial-selection task, Stroop test and categoric search attention task). Six of these studies also examined the effect of caffeine on event-related potentials (ERPs). The ERP is an electrophysiological measure of cortical activity which is time-locked to a specific stimulus event. The ERP is analysed into waves which vary in latency, amplitude and direction (negative and positive polarity). Different components of the ERP are associated with different mental operations. Of relevance to selective attention is the occurrence of the N2b negative wave 200 ms after stimulus onset. This N2b component is related to covert (internal) orienting of attention towards relevant information, and increased selective attention is identified by a greater amplitude in the N2b component.
Lorist et al. (1994b) reported that caffeine (250 mg, n=30 subjects per intervention arm, 18-25 years) significantly reduced RT in a selective attention task (p<0.02), but had no effect on performance accuracy. The Panel notes that faster response time, indicated by reduced RT, and with no associated increase in error rate, is evidence for improved attention and efficiency at processing information. In the same study, analysis of the ERP showed that the N2b amplitude was greater in the caffeine than in the placebo condition (p<0.03). Lorist et al. (1995) reproduced these findings in a sample of 15 young (18-23 years) and 15 older (60-72 years) subjects, where caffeine (250 mg, n=30 per intervention arm) significantly reduced RT on the same selective attention task (p=0.001) with no effects on accuracy. Additionally, the N2b amplitude was significantly increased in the caffeine compared to the placebo condition (p<0.03). Lorist et al. (1996) also observed a significant effect of caffeine (3 mg/kg body weight, n=16 subjects per intervention arm, 19-29 years) in the focused attention condition of a visual
selective search task. RT was significantly reduced (p=0.004), and the N2b amplitude was significantly increased (p<0.025). Lorist et al. (1994a) reported similar results in a study on the effects of caffeine on performance in three different tests of selective attention (stimulus degradation, stimulus-response compatibility and time uncertainty tasks). Significant effects of caffeine (250 mg, n=30 per intervention arm) were found in all tasks, with reduced RTs (p<0.004) and fewer errors (p<0.05). ERP measures were also obtained, but data on the N2b component were not reported. Ruijter et al. (2000a) found a significant effect of caffeine (250 mg, n=11 per intervention arm) on RT in a colour selection task (p=0.032) with no associated effects on errors. Ruijter et al. (2000a) also obtained ERP measures, and reported a significantly greater N2b amplitude in the caffeine group (p=0.023). In the same experiment (Ruijter et al., 2000b), no effect of caffeine was found on RT in a spatial selection task, albeit accuracy was significantly improved (p=0.029). The effect of caffeine on the N2b amplitude was not significant. Hogervost et al. (1999) reported a significant effect of caffeine at each of three different doses (150 mg, 225 mg or 320 mg, n=15 per intervention arm) on a Stroop test after strenuous exercise (p<0.05), but not before exercise. Frewer and Lader (1991) studied the effects of caffeine at two doses (250 mg or 500 mg, n=12 per intervention arm) on one- and two-target letter cancellation tasks. Caffeine at 250 mg produced significantly faster completion times compared to placebo on the one-target task (p<0.05), and at 500 mg on the two-target task (p<0.05). Hewlett and Smith (2007) observed no effects of caffeine (1 or 2 mg/kg body weight, n=30 or 60 subjects per intervention arm) on performance in a focused attention choice reaction time task and a categoric search task. Lorist and Snel (1997) failed to observe any significant effect of caffeine (3 mg/kg body weight, n=16 subjects per intervention arm) on performance in a visual selective attention task.
In summary, all 10 of these studies included participants who were habitual caffeine users who had avoided caffeine consumption for a period ranging from 7-24 hours. One study included groups of high- and low-caffeine users (Hewlett and Smith, 2007), but no effects of caffeine were observed in either group. Three of the 10 studies assessed the effects of different caffeine doses on measures of selective attention (Frewer and Lader, 1991; Hewlett and Smith, 2007; Hogervorst et al., 1999). Only Frewer and Lader (1991) reported any dose-related effects. Caffeine at 250 mg produced significantly faster completion times compared to placebo on a one-target letter cancellation task (p<0.05), but the effect of caffeine at 500 mg was not significant. These effects were reversed for a two-target task (250 mg: not significant; 500 mg: p<0.05).
The Panel notes that although there were notable differences in the duration of avoidance of caffeine prior to testing, and in the measures used to assess selective attention, overall a consistent effect of caffeine was observed on a variety of measures of selective attention (15 positive outcomes vs. 6 negative outcomes, from 10 trials).
A total of 14 studies examined the effect of caffeine on sustained attention (vigilance). Sustained attention was measured by a variety of psychometric tasks which included digit detection, rapid visual information processing, visual vigilance, continuous performance, 5-choice serial RT, Wilkinson auditory vigilance task and the Bakan vigilance task.
Fine et al. (1994) found that caffeine (200 mg, n=20 subjects per intervention arm) significantly increased the number of correct responses (p<0.0005) and decreased response times (p=0.002) compared to placebo in a visual vigilance task. Hasenfratz and Bättig (1994) reported that caffeine at three different doses (1.5 mg, 3 mg and 6 mg/kg body weight, n=20 per intervention arm) significantly decreased RT (p<0.01), but had no effects on processing rate compared to placebo in the rapid information processing task. No dose-response effect was observed in this study. Rosenthal et al. (1991) reported similar effects for two doses of caffeine (75 mg and 150 mg, n=12 subjects per intervention arm), both of which significantly reduced RT in an auditory vigilance task (p<0.001) with no effects on error rate. No dose-response effect was observed. Smith et al. (1990) showed that caffeine (3 mg/kg body weight, n=32 subjects per intervention arm) significantly improved performance on the Bakan vigilance task with reduced RT and better accuracy compared to placebo
(p<0.05). The effects were observed both before and after lunch. Smith et al. (1992) replicated these results in a study on the effects of caffeine (4 mg/kg body weight, n=24 subjects per intervention arm) on the Repeated Digits Vigilance Task. Caffeine significantly reduced RT (p<0.0001) and increased accuracy (p<0.0001), both before and after lunch. Smith et al. (1993) extended these findings to show that caffeine (1.5 or 3 mg/kg body weight, n=24 per intervention arm) significantly increased the number of correct responses on the 5-Choice Serial Response Task (p<0.005) at two different doses. These effects were found both during the day and at night. Frewer and Lader (1991) investigated the effects of caffeine (250 mg or 500 mg, n=12 subjects per intervention arm) on two different tests of sustained attention (rapid information processing task and continuous attention task). Accuracy in the rapid information processing task was significantly increased at both caffeine doses (p<0.02), but RT was significantly reduced only at the higher 500 mg dose (p<0.01). Caffeine at both doses significantly improved accuracy in the continuous attention task (p<0.05). Lieberman et al. (1987) investigated the effects of caffeine (32 mg, 64 mg, 128 mg and 256 mg, n=20 subjects per intervention arm) on three different tests of sustained attention (Wilkinson auditory vigilance task, continuous performance task, 4-choice visual RT). Caffeine at all doses significantly improved accuracy on the Wilkinson auditory vigilance task (p<0.0016), and significantly reduced RT on the 4-choice visual RT test (p=0.02), with no accompanying effects on accuracy. No effects of caffeine were observed on the continuous performance task. Warburton (1995) examined the effects of caffeine (75 mg and 150 mg, n=18 subjects per intervention arm) on the rapid information processing test in participants with minimal caffeine deprivation. There was a significant effect of caffeine on performance accuracy (p<0.01), with greater accuracy occurring in the 150 mg condition compared to placebo. A significant reduction in RT was also observed in the caffeine compared to placebo conditions (p<0.05), which was also dose related (p<0.05). Smit and Rogers (2000) studied the effects of caffeine (12.5 mg, 25 mg, 50 mg and 100 mg; n=23 subjects per intervention arm) on the rapid visual processing task in habitual high- and low-caffeine users. Caffeine at all doses significantly improved performance of high-caffeine users (p<0.004), but had no effect on the performance of low-caffeine users, and there were no effects on RT in either group.
Two further studies examined the effects of caffeine on sustained attention in sleep-deprived individuals. Bonnet et al. (1995) studied the effects of either a single dose (400 mg) or repeated doses (150-300 mg every 6 hours for 42 hours) of caffeine on performance in a visual vigilance test in participants with varying durations of sleep deprivation. There were 27 participants in the placebo group, 17 in the 150-300 mg group, and 12 in the 400 mg group. Visual vigilance performance was significantly improved in the caffeine groups, but only up to 24 hours sleep deprivation (group x time interaction p<0.001). Lieberman et al. (2002) studied the effects of caffeine (100 mg, 200 mg and 300 mg, n=17 subjects per intervention arm) in participants who underwent 72 hours sleep deprivation as well as physical and environmental stress challenges prior to receiving their caffeine intervention. Performance was measured in two tests of sustained attention (4-choice visual RT test and scanning visual vigilance test). Caffeine produced significant beneficial, dose-related effects including an increase in the number of correct responses (p=0.0464) and a decrease in RT (p=0.0418) on the scanning visual vigilance test. Significantly more correct responses in the 4-choice visual RT test were shown by both the 200 mg and 300 mg caffeine groups compared to placebo, at one hour after caffeine intake (p<0.05).
Two studies found no effects of caffeine on measures of sustained attention. Ruijter et al. (2000c) found no effects of caffeine (250 mg; n=12 subjects per intervention arm) on performance in a sustained attention task (a modified Bourdon test). The authors noted that the attention test used was more cognitively demanding than other sustained attention tests. Hewlett and Smith (2007) observed no effects of caffeine (1 or 2 mg/kg body weight, n=30 or 60 per intervention arm) on performance in a repeated digit detection task administered for five minutes. The Panel notes that the duration of this task may have been insufficient for an adequate assessment of sustained attention.
In summary, nine out of the 14 studies included participants who were habitual caffeine users and who had avoided caffeine consumption for a period ranging from three hours to one week. Four studies compared the effects of caffeine in groups of high- and low-caffeine users (Fine et al., 1994; Hewlett and Smith, 2007; Lieberman et al., 1987; Smit and Rogers, 2000), who had avoided caffeine consumption for 7-12 hours. Two of these studies reported significant effects of caffeine on sustained attention performance and which were the same in both high- and low-caffeine users (Fine et al., 1994; Lieberman et al., 1987). One study (Smit and Rogers, 2000) reported significant effects of caffeine in high-caffeine users, but no effects in low-caffeine users. Hewlett and Smith (2007) found no effects of caffeine in either high- or low-caffeine users, but the duration of the test period may have been insufficient for adequate assessment of sustained attention.
Ten of the 14 studies assessed the effects of different caffeine doses on measures of selective attention (Bonnet et al., 1995; Frewer and Lader, 1991; Hasenfratz and Bättig, 1994; Hewlett and Smith, 2007; Lieberman et al., 1987; 2002; Rosenthal et al., 1991; Smit and Rogers, 2000; Smith et al., 1993; Warburton, 1995). Two studies reported significant dose-related effects. Warburton (1995) found greater rapid information processing test accuracy in both 75 mg and 150 mg caffeine groups compared to placebo, and the effect was greater in the 150 mg group (p<0.01). RT was significantly reduced in both caffeine groups (p<0.05), and this effect was also dose related (p<0.05). Lieberman et al. (2002) examined the effects of three doses of caffeine (100 mg, 200 mg and 300 mg) on visual vigilance test performance, and reported a significant linear increase in accuracy with increasing caffeine intake (p<0.05).
The Panel notes that although there were notable differences in the duration of avoidance of caffeine prior to testing and in the measures used to assess sustained attention, overall a consistent effect of caffeine was observed on a variety of measures of sustained attention (35 positive outcomes vs. 12 negative outcomes, from 14 trials).
Overall, the Panel notes the consistency of the results of studies on both selective and sustained attention, with a majority showing positive effects of caffeine. Although some effects have been observed at very low caffeine doses (<75 mg), results were inconsistent (Hewlett and Smith, 2007; Lieberman et al., 1987; Smit and Rogers, 2000). The majority of significant results were obtained when subjects consumed caffeine doses in the range of 75-500 mg. This finding is consistent with consensus opinions reporting on caffeine doses in the range of 100-400 mg (IoM, 2001) and of 60-600 mg (ANZFA, 2000) which have consistently demonstrated an effect of caffeine on tests of attention.
In weighing the evidence, the Panel took into account that the evidence provided by consensus opinions/reports and by the majority of the studies submitted for the scientific substantiation of the claim showed that there was good consensus on the role of caffeine in increasing attention, measured by a range of psychometric tasks, in healthy individuals of both sexes, at doses of at least 75 mg.
The Panel concludes that a cause and effect relationship has been established between the consumption of caffeine and increased attention.

4.2. Zwiększenie uwagi (ID 736, 1485, 1491, 2375)

The Panel considers that the following wording reflects the scientific evidence: “Caffeine helps to improve concentration”.

5. Warunki i możliwe ograniczenia stosowania oświadczenia

The Panel considers that, in order to bear the claim, a product should contain at least 75 mg caffeine per serving. The target population is the general adult population.
For children, consumption of a dose of 5 mg/kg body weight could result in transient behavioural changes, such as increased arousal, irritability, nervousness or anxiety (SCF, 1999). In relation to pregnancy and lactation, moderation of caffeine intake, from whatever source, is advisable. A European Commission Directive lays down rules for the labelling of foodstuffs containing caffeine (Directive 2002/67/EC6).

Warunki i możliwe ograniczenia stosowania oświadczenia

Minimum 150 mg guarana extract, containing 10% caffein/portion or seed equivalent with this. ;;