ID 299 -
Cynk
PL: Cynk
EN: Zink
Pdf: zinc
Oświadczenie (2)
- niezbędnych do utrzymania optymalnego funkcjonowania mięśni
1. Charakterystyka żywności / składnika
The food constituent that is the subject of the claims is zinc, which is a well recognized nutrient and is measurable in foods by established methods. Zinc occurs naturally in foods and is authorised for addition to foods (Annex I of the Regulation (EC) No 1925/20064 and Annex I of Directive 2002/46/EC5). This evaluation applies to zinc 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, zinc, which is the subject of the health claims, is sufficiently characterised.
2.8. Funkcje mięśni (ID 299)
The claimed effect is “required to maintain optimal muscle function”. The Panel assumes that the target population is the general population.
The Panel considers that normal muscle function is beneficial to human health.
3. Naukowe uzasadnienia wpływu na zdrowie człowieka -
Zinc is present in all tissues. It has essential structural, regulatory or catalytic roles in many enzymes. It maintains the configuration of a number of non-enzymatic proteins such as pre-secretory granules of insulin, some mammalian gene transcription proteins and thymulin. It facilitates hormone and receptor binding at membrane and nuclear levels, and it may maintain integrity of biomembranes. Consequently zinc participates in gene expression and in the mechanisms and control of major metabolic pathways involving proteins, carbohydrates, nucleic acids and lipids (SCF, 1993; DoH, 1991). Human zinc deficiency symptoms include retarded growth, depressed immune function, skin lesions, skeletal abnormalities, impaired reproductive ability and behavioural abnormalities such as changes in mood, loss of affect and emotional lability, anorexia, dysfunction of smell and taste, irritability and depression (SCF, 2003; EVM, 2002, Cousins, 2006).
3.7. Funkcje mięśni (ID 299)
A total of six references were cited for the substantiation of the claimed effect. Four studies dealt with outcomes unrelated to the claimed effect such as serum testosterone levels and blood rheology during exercise and physical performance. The Panel notes, that these references did not provide any scientific data that could be used to substantiate the claimed effect.
In one double-blind cross over study with 16 women the effect of zinc on muscle strength and endurance, followed by zinc supplementation (135 mg/day for 14 days) was assessed using isometric and isokinetic tests of the knee extensor and flexor muscle groups . After zinc treatment, a significant increase in isometric endurance but not in dynamic endurance was observed (Krotkiewski et al., 1982). The Panel notes the small size of the study and the lack of information on the overall nutritional status of intervention and control groups. The Panel also notes that the dose administered in this study is above the established upper intake level of 25 mg/day for zinc.
In a zinc repletion depletion study with eight men, the effect of zinc on isokinetic peak force and total work capacity was assessed. The peak force of the muscle groups tested was not affected by acute zinc depletion, but total work capacity for the knee extensor muscles and shoulder extensor and flexor muscles significantly declined (Van Loan et al., 1999).The Panel notes the small size of the study.
The Panel concludes that a cause and effect relationship has not been established between the dietary intake of zinc and normal muscle function.
5. Warunki i możliwe ograniczenia stosowania oświadczenia
The Panel considers that in order to bear the claim a food should be at least a source of zinc as per Annex to Regulation (EC) No 1924/2006. The target population is the general population. Such amounts can be easily consumed as part of a balanced diet. Tolerable Upper Intake Levels (UL) have been established for zinc as 25 mg/day in adults and to pregnant and lactating woman. For children and adolescents UL was established as 7 mg/day for 1-3 years, 10 mg/day for 4-6 years, 13 mg/day for 7-10 years, 18 mg/day for 11-14 years and 22 mg/day for 15-17 years (SCF 2003).
Warunki i możliwe ograniczenia stosowania oświadczenia
Minimum of 12 mg zinc per day
Must meet minimum requirements for use of the claim "source of [name of vitamin/s] and/or [name of mineral/s)" as per Annex to Regulation 1924/2006.
Agency guidance for supplements is that products containing >25mg zinc should carry the label statement: 'Long term intake [of this amount of zinc] may lead to anaemia.'