ID 124 - Witamina K

PL: Witamina K
EN: Vitamin K
Pdf: vitamin K2

Oświadczenie (4)

Oświadczenie (2)

1. Charakterystyka żywności / składnika

The food constituent that is the subject of the health claim is vitamin K (i.e. phylloquinone and menaquinone) which is a well recognized nutrient and is measurable in foods by established methods.
Vitamin K is a family of structurally similar, fat soluble, 2-methyl-1, 4-naphthoquinones, including phylloquinone (2-methyl-3-phytyl-1,4-naphthoquinone, vitamin K1) and menaquinones (collectively known as vitamin K2). Menaquinones are a large series of compounds containing an unsaturated side chain with differing numbers of isoprenyl units at the 3 position in the methyl-1,4-naphthoquinone nucleus. Depending on the number of isoprenyl units, the individual compounds are designated as menaquinone-n-(MK-n). Phylloquinone (vitamin K1) is found in higher plants and algae, with the highest concentration in green leafy vegetables. Menaquinones (vitamin K2) occur naturally in foods and can also be produced by many bacteria.
Phylloquinone and menaquinones are naturally present in foods and phylloquinone has been authorised for addition to foods and for use in food supplements (Annex II of the Regulation (EC) No 1925/20064 and Annex I of Directive 2002/46/EC5). This evaluation applies to vitamin K naturally present in foods and to the form authorised for addition to foods and for use in food supplements (Annex II of the Regulation (EC) No 1925/2006 and Annex II of Directive 2002/46/EC).
The Panel considers that the food constituent, vitamin K, which is the subject of the health claim, is sufficiently characterised.

2.2. Krzepnięcie krwi (ID 124, 126)

The claimed effects are “heart health” and “blood coagulation”. The Panel assumes that the target population is the general population.
The Panel considers that normal blood coagulation is beneficial to human health.

2.3. Funkcjonowanie serca i naczyń krwionośnych (ID 124, 125 2880)

The claimed effects are “cardiovascular health”, “vascular health”, 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 effects relate to the normal function of the heart and blood vessels.
The Panel considers that the normal function of the heart and blood vessels is beneficial to human health.

3. Naukowe uzasadnienia wpływu na zdrowie człowieka - 

Proteins containing γ-carboxy-glutamic acid (Gla) residues are known to be dependent on vitamin K for their synthesis. These include (but are not limited to) the plasma clotting factors II, VII, IX, X; proteins S, C and Z (which play an anticoagulant rather than a procoagulant role in normal haemostasis); and osteocalcin and matrix Gla protein (MGP), which are abundant in bone and appear to play a role in the control of tissue mineralisation and skeletal turnover.
Vitamin K status is determined through measures of the ratio of carboxylated to non carboxylated vitamin K – dependent proteins.

3.2. Krzepnięcie krwi (ID 124, 126)

Vitamin K is needed for the normal function of many of the enzymes involved in the coagulation cascade through carboxylation of glutamic acid in the side chain, and hence allowing calcium fixation (IoM, 2001).
Restriction of vitamin K intakes to levels almost impossible to achieve in any nutritionally adequate, self-selected diet (10 µg/day for several weeks) do not impair normal haemostatic control in healthy subjects. Although there is some interference in the hepatic synthesis of the vitamin K-dependent clotting factors that can be measured by sensitive assays, standard clinical measures of pro-coagulant potential are not changed, except in some breast-fed infants.
The Panel concludes that a cause and effect relationship has been established between the dietary intake of vitamin K and normal blood coagulation.

3.3. Funkcjonowanie serca i naczyń krwionośnych (ID 124, 125, 2880)

Vitamin-K dependent proteins have been identified in vascular tissue, including a matrix Gla-protein (MGP). In a MGP knockout mouse model, spontaneous calcification of soft tissues (mostly arteries) occurs (Luo et al., 1997). In the Keutel syndrome, due to a mutation of the gene encoding the human MGP, patients display several of the same features as the knockout mice, including abnormal calcification of cartilage of ears, nose, and respiratory tract. However, they do not appear to have increased incidence of coronary arterial disease or rupture of abdominal aortic aneurysm (Munroe et al., 1999).
The health claims (ID 124, 125 and 2880) are made on vitamin K2. From the literature available, four papers refer to the role of vitamin K from all sources and/or vitamin K2 in relation to the heart and/or blood vessels (Jie et al., 1995; Maas et al., 2007; Geleijnse et al., 2004; Beulens et al., 2009). The Panel considers that studies investigating the relationship between vitamin K intake (from all sources and/or as vitamin K2) and arterial calcification or the elastic properties of the arteries (which may interfere with normal vascular structure and function) are pertinent to the claimed effect.
Three cross-sectional studies investigated the relationship between vitamin K intake and arterial calcification in women. Whereas one study found lower vitamin K (mainly vitamin K1) intakes in women with aortic atherosclerosis (Jie et al., 1995) as compared to controls, another study reported that vitamin K2 (but not vitamin K1) intake was inversely related to the presence of coronary calcification (Beulens et al., 2008), and the third showed no association between either vitamin K1 or vitamin K2 intake and breast arterial calcification after adjustment for confounders (Maas et al., 2007).
An observational prospective study in 4,807 older men and women found that high intakes of vitamin K2 (but not of K1) were associated with a significantly lower degree of aortic calcification and lower incidence of coronary heart disease after adjustment for confounders (Geleijnse et al., 2004). The Panel notes that no definite conclusion can be drawn from this single prospective study on a causal link between the intake of vitamin K2 and the normal function of the heart and blood vessels.
In weighing the evidence, the Panel took into account the inconsistency of the results reported in three cross-sectional studies, and that no definite conclusion can be drawn from a single prospective study on a causal link between the intake of vitamin K2 and the normal function of the heart and blood vessels.
The Panel concludes that the evidence provided is insufficient to establish a cause and effect relationship between the dietary intake of vitamin K2 and the normal function of the heart and blood vessels.

4.2. Krzepnięcie krwi (ID 124, 126)

The Panel considers that the following wording reflects the scientific evidence: “Vitamin K contributes to normal blood coagulation”.

5. Warunki i możliwe ograniczenia stosowania oświadczenia

The Panel considers that in order to bear the claims a food should be at least a source of vitamin K as per Annex to Regulation 1924/2006. Such amounts can be easily consumed as part of a balanced diet. The target population is the general population.

Warunki i możliwe ograniczenia stosowania oświadczenia

Source of / 15% of RDA per 100 g