ID 1114 - Katechiny z zielonej herbaty

PL: Katechiny z zielonej herbaty
EN: Catechins – Green tea (camellia sinensis)
Pdf: Camellia sinensis

Oświadczenie (2)

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.

2.7. Utrzymanie prawidłowego stężenia cholesterolu we krwi (ID 1113, 1114)

The claimed effects are “cholesterol” and “heart health”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel notes that the claimed effect relates to the maintenance of normal blood cholesterol concentrations.
Low-density lipoproteins (LDL) carry cholesterol from the liver to peripheral tissues, including the arteries. Elevated LDL-cholesterol, by convention >160mg/dL, may compromise the normal structure and function of the arteries.
The Panel considers that maintenance of normal blood cholesterol concentrations is a beneficial physiological effect.

3.7. Utrzymanie prawidłowego stężenia cholesterolu we krwi (ID 1113, 1114)

Two human intervention studies (Erba et al., 2005; Maron et al., 2003) on the effects of green tea catechins on blood cholesterol concentrations and three observational studies on the association between tea consumption and total/LDL-cholesterol concentrations (Tokunaga et al., 2002; Kono et al., 1996; Imai and Nakachi, 1995) were cited in relation to this claim. Three additional human
intervention studies were cited in the publication by Maron et al., (2003) and were considered by the Panel as pertinent to the claim (Princen et al., 1998; van het Hof et al., 1997; Duffy et al., 2001).
In a randomised, placebo-controlled intervention trial (RCT), daily consumption of two cups of green tea containing 250 mg per day total catechins during six weeks did not affect serum total, LDL-, or HDL-cholesterol concentrations in 12 healthy women compared with 12 control women not consuming green tea (Erba et al., 2005). In another parallel comparison RCT, 45 volunteers (aged 18-65 years) were randomised to consume 900 mL per day (6 cups per day) mineral water, 3 g green tea extract (21.4% by weight catechins) or 3 g black tea extract (7.2% by weight catechins) diluted in the same amount of water (900 mL) for four weeks. Consumption of either green or black tea did not change significantly blood lipid concentrations as compared to controls (van het Hof et al., 1997).
Similarly, in a RCT with parallel design, healthy male and female smokers (aged 34 12 years, 13 to 16 subjects per group) consumed 6 cups (900 mL) of either black, green tea or water per day, or received as a supplement 3.6 grams of green tea polyphenols per day (2.5 g per day green tea catechins equivalent to the consumption of 18 cups of green tea per day) for four weeks. Consumption of black tea, green tea or green tea polyphenols had no effect on plasma triglycerides, total-, HDL- or LDL-cholesterol concentrations (Princen et al., 1998). The effect of a theaflavin-enriched green tea extract, 375 mg per day including 75 mg theaflavin, 150 mg green tea catechins, and 150 mg other green tea polyphenols, was studied in 120 Chinese subjects with mild to moderate hypercholesterolaemia in parallel comparison with another 120 subjects who consumed placebo capsules (Maron et al., 2003). The Panel notes that theaflavins are oxidised catechins naturally present in black tea in significant amounts, whereas they are not a major component of green tea catechins. The Panel considers that no conclusions can be drawn from this study for the substantiation of the claim.
In some epidemiological studies, the relationship between green tea consumption and blood total- and LDL-cholesterol concentrations were investigated after adjustment for confounders (Tokunaga et al., 2002; Kono et al., 1996; Imai and Nakachi, 1995). None of these studies reported daily consumption of the food constituent (green tea catechins) that is the subject of the health claim. The Panel considers that no conclusions can be drawn from these studies for the substantiation of the claim.
In weighing the evidence, the Panel took into account that the three small-scale human RCTs presented failed to observe an effect of green tea catechin consumption on blood cholesterol concentrations.
The Panel concludes that a cause and effect relationship has not been established between the consumption of catechins in green tea (Camellia sinensis (L.) Kuntze) and maintenance of normal blood cholesterol concentrations.

Warunki i możliwe ograniczenia stosowania oświadczenia

Recommended dosage 500-1000 mg catechins 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.