ID 1111 -
Katechiny z zielonej herbaty
PL: Katechiny z zielonej herbaty
EN: Catechins – Green tea (camellia sinensis)
Pdf: Camellia sinensis
1. Charakterystyka żywności / składnika
The food constituent that is the subject of the health claims is Camellia sinensis (L.) Kuntze, catechins present in green tea, and epigallo-catechin-3-gallate.
In the wording of claim ID 1105, tannins and fluoride are named as active ingredients in tea in relation to a claimed effect on oral health. The Panel refers to its previous opinion on fluoride in the context of the evaluation of Article 13 claims (EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA), 2009); the effects of fluoride (irrespective of the source) on tooth mineralisation will not be considered further in this Opinion.
The plant Camellia sinensis (L.) Kuntze is an evergreen shrub of the Theaceae family. Tea is an extract of the dried leaves from Camellia sinensis (L.) Kuntze and it is usually prepared by infusing the leaves in hot water. The composition of the tea leaves depends on a variety of factors, including climate, season, horticultural practices, and the type and age of the plant. Many kinds of tea are produced, which can be classified into three major types according to the different levels of fermentation: green (un-fermented), oolong (semi-fermented) and black (fully fermented) (Wang et al., 2000).
The composition of tea beverages greatly depends on the type of leaves used, on the degree of fermentation and on the methods of preparation (Kaszkin et al., 2004; Astill et al., 2001). The level of fermentation, the production process, and the method for preparing the tea infusion have not been described in relation to the claims.
Green tea contains polyphenolic compounds, which include flavanols, flavandiols, flavonoids, and phenolic acids. Most of the polyphenols in green tea are catechins. Epigallo-catechin-3-gallate (EGCG) is the most abundant catechin in green tea. In black teas, the most abundant polyphenols are tannins, mainly theaflavin and thearubigin (Mukhtar and Ahmad, 2000). Tea extracts/infusions also contain variable amounts of potentially active food constituents, such as caffeine, theanine or theogallin.
Green tea catechins (including EGCG) and tannins in black tea (mainly theaflavin and thearubigin) can be measured in foods by established methods.
The Panel considers that whereas Camellia sinensis (L.) Kuntze (tea) is not sufficiently characterised in relation to the claimed effects, catechins in green tea (including EGCG) and tannins in black tea (for ID 1105) are sufficiently characterised.
2.2. Zmniejszenie produkcji kwasu w osadzie nazębnym (ID 1105, 1111)
The claimed effects are “oral health” and “teeth”. 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 relates to the reduction of acid production in dental plaque.
Plaque formation is a stepwise building of a bacterial biofilm on teeth and soft tissues, i.e. a highly specific initial attachment of bacteria to host receptors (saliva, cells), followed by secondary attachment of bacteria binding to already colonising bacteria. Fermentation of carbohydrates in the mouth by acid-producing bacteria lowers plaque pH, which contributes to demineralisation of tooth tissues (Marsh and Nyvad, 2008).
The Panel considers that reduction of acid production in dental plaque is a beneficial physiological effect.
3.2. Zmniejszenie produkcji kwasu w osadzie nazębnym (ID 1105, 1111)
Publications provided dealing with the effects, intake or bioavailability of food constituents other than Camellia sinensis (L.) Kuntze, tea, tannins in black tea or catechins in green tea (e.g., fluoride, tannic acid, gallotannins from Melaphis chinensis), with the composition of teas, or with claimed effects other than the reduction of acid production in the dental plaque or plaque acid neutralisation (e.g., dental caries, colonisation and glucan production by mutans streptococci, intra oral hydrolysis of complex carbohydrates) were not considered to be pertinent to the claim as no scientific conclusions can be drawn from these references to substantiate the claim.
In one non-controlled intervention study in humans, ten healthy young adults were monitored for tooth surface pH on the palatal aspects of the maxillary anterior and the maxillary molar dentition after drinking black tea (Simpson et al., 2001). The Panel notes the uncontrolled nature of the study, the small number of subjects, the lack of statistical analysis, the fact that pH was only measured on the teeth surface (which greatly depends on the pH of the beverage being consumed) but not acid production, and that the amount of tannins in black tea was not reported.
Two in vitro studies on the effects of green and black tea on the inhibition of growth of different bacteria were presented (Sakanaka et al., 1990; Rasheed and Haider 1998). The Panel considers that the evidence provided in in vitro studies is not sufficient to predict the occurrence of an effect of the consumption of either catechins or tannins in Camellia sinensis (L.) Kuntze on the reduction of acid production in dental plaque.
The Panel notes that no human studies which measured acid production were presented.
The Panel concludes that a cause and effect relationship has not been established between the consumption of either catechins or tannins in Camellia sinensis (L.) Kuntze and reduction of acid production in dental plaque.
Warunki i możliwe ograniczenia stosowania oświadczenia
Recommended dosage 500 -1000 ppm
Catechins are active and functional polyphenol components of green tea leaves.
One cup (200ml) of brewed green tea may contain 100-150 mg of catechins.or equivalent of 50-60mg of EGCG.
The usual consumption of green tea is about 5-10 cups per day, which is equivalent to 500-1200 mg of catechins or 250-600 mg of EGCG per day.