ID 73 -
Witamina B6
PL: Witamina B6
EN: Vitamin B6
Pdf: vitamin B6
Oświadczenie (4)
- Witamina B6 przyczynia się do prawidłowego metabolizmu homocysteiny
Oświadczenie (2)
- homocysteiny
- zdrowie serca
- metabolizm homocysteiny
1. Charakterystyka żywności / składnika
The food constituent that is the subject of the health claims is vitamin B6, which is a group of compounds comprising three free forms, pyridoxine, pyridoxal, pyridoxamine, and their 5'-phosphates derivatives (PNP, PLP and PMP). Vitamin B6 occurs naturally in foods, mainly as pyridoxal phosphate (animals), pyridoxine beta-glucoside (plants) and some pyridoxyl peptides (processed foods). Vitamin B6 is a well recognised nutrient and is measurable in foods by established methods.
Vitamin B6 is authorised for addition to foods (Annex I of the Regulation (EC) No 1925/20066 and Annex I of Directive 2002/46/EC7). This evaluation applies to vitamin B6 naturally present in foods and those forms authorised for addition to foods (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 B6, which is the subject of the health claims is sufficiently characterised.
2.1. Udział w prawidłowym metabolizmie homocysteiny (ID 73, 76, 199)
The claimed effects are “homocysteine levels”, “homocysteine metabolism” and “heart health”. The Panel assumes that the target population is the general population.
In the context of the proposed wording for ID 76, the Panel assumes that the claimed effect refers to homocysteine metabolism.
The Panel considers that contribution to normal homocysteine metabolism is a beneficial physiological effect.
8
3. Naukowe uzasadnienia wpływu na zdrowie człowieka
Vitamin B6 functions as a coenzyme in a variety of enzymatic reactions in the metabolism of amino acids, one-carbon units, lipids, the pathways of gluconeogenesis, haem, and neurotransmitter biosynthesis (McCormick, 2006; Mackey et al., 2006).
3.1. Udział w prawidłowym metabolizmie homocysteiny (ID 73, 76, 199)
The transsulphuration pathway is an alternative metabolic route to remethylation of homocysteine to methionine. The pathway utilises the pyridoxal phosphate-dependent enzymes, cystathionine β-synthase and cystathionine γ-lyase, and catabolises homocysteine through condensation with serine to cystathionine, followed by cleavage of that molecule to produce cysteine and α-ketobutyrate (Mackey et al., 2006).
Under conditions of maximal metabolic efficiency, plasma concentration of homocysteine ranges from 4 to 10 µmol/L. Metabolic blocks in homocysteine metabolism lead to accumulation of intra- cellular homocysteine with subsequent export into the blood. Depending on the magnitude of the metabolic impairment, plasma homocysteine can rise to varying degrees. Hyperhomocysteinemia is also caused by B vitamin deficiencies. Deficiencies of folate, vitamin B6 and vitamin B12 lead to impaired homocysteine metabolism causing mild, moderate, or severe elevations in plasma homocysteine, depending on the severity of the deficiency, as well as the coexistence of genetic or other factors that interfere with homocysteine metabolism (Miller, 2005).
The Panel concludes that a cause and effect relationship has been established between the dietary intake of vitamin B6 and contribution to normal homocysteine metabolism.
4.1. Udział w prawidłowym metabolizmie homocysteiny (ID 73, 76, 199)
The Panel considers that the following wording reflects the scientific evidence: “Vitamin B6 contributes to normal homocysteine metabolism”.
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 B6 as per Annex to Regulation (EC) No 1924/2006. Such amounts can be easily consumed as part of a balanced diet. The target population is the general population. Tolerable Upper Intake Levels (ULs) have been established for vitamin B6 in children, adolescents and adults (SCF, 2000).
Warunki i możliwe ograniczenia stosowania oświadczenia
15% RDA per 100 Source of / 15% of RDA per 100 g
Agency guidance for supplements is that products containing >10 mg of vitamin B6 should carry the label advisory statement "Long term intakes [of this amount of vitamin B6] may lead to mild tingling and numbness"