Scientific Opinion on the substantiation of health claims related to
vitamin B12 and contribution to normal neurological and psychological
functions (ID 95, 97, 98, 100, 102, 109), contribution to normal
homocysteine metabolism (ID 96, 103, 106), maintenance of normal bone
(ID 104), maintenance of normal teeth (ID 104), maintenance of normal
hair (ID 104), maintenance of normal skin (ID 104), maintenance of normal
nails (ID 104), reduction of tiredness and fatigue (ID 108), and cell division
(ID 212) pursuant to Article 13(1) of Regulation (EC) No 1924/2006[sup]1[/sup]
EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA)2, 3
European Food Safety Authority (EFSA), Parma, Italy
Słowa kluczowe:
Vitamin B12
bone
cell division
fatigue
hair
health claims
homocysteine
nails
neurological
psychological
skin
teeth
1. Charakterystyka żywności / składnika
The food constituent that is the subject of the health claims is vitamin B12, which is a specific group of cobalt-containing corrinoids with biological activity in humans. Recommended biochemical nomenclature restricts the term vitamin B12 for the particular form of cobalamin known as cyanocobalamin and all cobalamins exhibiting qualitatively the biological activity of cyanocobalamin. Cobalamins do not occur in plants but are synthesised by certain bacteria, fungi and algae, which constitute the ultimate source of all cobalamin found in nature (Green, 2005). Vitamin B12 is a well recognised nutrient and is measurable in foods by established methods.
Vitamin B12 occurs naturally in foods and is authorised for addition to foods and for use in food supplements (Annex I of the Regulation (EC) No 1925/20066 and Annex I of Directive 2002/46/EC7). This evaluation applies to vitamin B12 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 B12, which is the subject of the health claims, is sufficiently characterised.
2. Znaczenie oświadczenia dla zdrowia człowieka
2.1. Udział w prawidłowym przebiegu funkcji neurologicznych i psychicznych (psychologicznych) (ID 95, 97, 98, 100, 102, 109)
The claimed effects are “neurological system: structure and function”, “cognitive function in ageing”, “nerve system and cognitive function”, “the role of vitamins and minerals in mental performance (where mental performance stands for those aspects of brain and nerve functions which determine aspects like concentration, learning, memory and reasoning)”. The Panel assumes that the target population is the general population.
The Panel notes that the claimed effects relate to neurological and psychological functions.
The Panel considers that contribution to normal neurological and psychological functions, which encompass cognitive and affective domains, is a beneficial physiological effect.
2.2. Udział w prawidłowym metabolizmie homocysteiny (ID 96, 103, 106)
The claimed effects are “homocysteine metabolism”, “homocysteine levels”, and “heart health”. The Panel assumes that the target population is the general population.
In the context of the proposed wording for ID 106, the Panel assumes that the claimed effect is related to normal homocysteine metabolism.
The Panel considers that contribution to normal homocysteine metabolism is a beneficial physiological effect.
2.3. Utrzymanie prawidłowego stanu kości (ID 104)
The claimed effect is “bone/teeth/hair/skin and nail health”. The Panel assumes that the target population is the general population.
The Panel considers that maintenance of normal bone is a beneficial physiological effect.
2.4. Utrzymanie prawidłowego stanu zębów (ID 104)
The claimed effect is “bone/teeth/hair/skin and nail health”. The Panel assumes that the target population is the general population.
The Panel considers that maintenance of normal teeth is a beneficial physiological effect.
2.5. Utrzymanie prawidłowego stanu włosów (ID 104)
The claimed effect is “bone/teeth/hair/skin and nail health”. The Panel assumes that the target population is the general population.
The Panel considers that maintenance of normal hair is a beneficial physiological effect.
2.6. Utrzymanie prawidłowego stanu skóry (ID 104)
The claimed effect is “bone/teeth/hair/skin and nails health”. The Panel assumes that the target population is the general population.
The Panel considers that maintenance of normal skin is a beneficial physiological effect.
2.7. Utrzymanie prawidłowego stanu paznokci (ID 104)
The claimed effect is “bone/teeth/hair/skin and nail health”. The Panel assumes that the target population is the general population.
The Panel considers that maintenance of normal nails is a beneficial physiological effect.
2.8. Zmniejszenie zmęczenia (ID 108)
The claimed effect is “vitamin/mineral supplementation to reduce fatigue and tiredness in situations of inadequate micronutrient status”. The Panel assumes that the target population is the general population.
The Panel considers that reduction of tiredness and fatigue is a beneficial physiological effect.
2.9. Podziały komórek (ID 212)
The claimed effect is “supports folic acid metabolism, in succession: DNA synthesis”. The Panel assumes that the target population is the general population.
In the context of the clarifications provided by Member States, the Panel assumes that the claimed effect is related to cell division.
A claim on vitamin B12 and normal cell division has already been assessed with a favourable outcome (EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA), 2009).
3. Naukowe uzasadnienia wpływu na zdrowie człowieka -
The two forms of vitamin B12 that function as coenzymes for metabolic reactions are methylcobalamin and 5'-deoxyadenosylcobalamin.
3.1. Udział w prawidłowym przebiegu funkcji neurologicznych i psychicznych (psychologicznych) (ID 95, 97, 98, 100, 102, 109)
Vitamin B12 has a central role in the normal functions of the brain and nervous system. It is well established from clinical studies that vitamin B12 deficiency produces adverse neurological effects owing to demyelination in the spinal cord, brain, and optic and peripheral nerves (Allen et al., 1996; Gibney et al., 2002; Wynn and Wynn, 1998). Serious vitamin B12 deficiency leads to an irreversible polyneuropathy. Clinical signs include e.g. abnormal proprioception, taste, smell and vision, irritability, memory loss, dementia, ataxia (Allen et al., 1996; Gibney et al., 2002; Wynn and Wynn, 1998).
The Panel concludes that a cause and effect relationship has been established between the dietary intake of vitamin B12 and contribution to normal neurological and psychological functions.
3.2. Udział w prawidłowym metabolizmie homocysteiny (ID 96, 103, 106)
Methylcobalamin, a coenzyme form of vitamin B12, is involved in the remethylation of homocysteine to methionine by the methionine synthase which requires both folate and vitamin B12 as cofactors (Stabler, 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. Deficiencies of folate, vitamin B6 and vitamin B12 lead to impaired remethylation of homocysteine causing mild, moderate, or severe elevations in plasma homocysteine, depending on the severity of the deficiency, as well as 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 B12 and contribution to normal homocysteine metabolism.
3.3. Utrzymanie prawidłowego stanu kości (ID 104)
A total of nine references were provided, including three textbooks, two opinions from authoritative bodies, one review and three human studies.
One textbook mentioned that cobalamin deficiency had been described in association with reduced bone-derived alkaline phosphatase and osteocalcin in the plasma (Green, 2005). Two studies solely dealt with the putative role of homocysteine as a potential risk factor for the development of osteoporosis (McLean et al., 2004; Van Meurs et al., 2004), without referring to vitamin B12. Dhonukshe-Rutten et al. (2005) reported that high plasma concentrations of homocysteine and low serum concentrations of vitamin B12 and especially the combination of these two parameters were related to high fracture risk, low broadband ultrasound attenuation, and increased bone turnover markers, as studied in 1,267 subjects of the Longitudinal Aging Study Amsterdam. The Panel notes that no conclusions on a causal relationship between the dietary intake of vitamin B12 and the claimed effect can be drawn from this study because residual confounding by other dietary and lifestyle factors inherent in the observational study design cannot be excluded.
The Panel concludes that a cause and effect relationship has not been established between the dietary intake of vitamin B12 and maintenance of normal bone.
3.4. Utrzymanie prawidłowego stanu zębów (ID 104)
A total of nine references were provided, including three textbooks, two opinions from authoritative bodies, one review and three human studies, which were unrelated to the claimed effect. The Panel considers that no conclusions could be drawn for the scientific substantiation of the claimed effect.
The Panel concludes that a cause and effect relationship has not been established between the dietary intake of vitamin B12 and maintenance of normal teeth.
3.5. Utrzymanie prawidłowego stanu włosów (ID 104)
A total of nine references were provided, including three textbooks, two opinions from authoritative bodies, one review and three human studies, which were unrelated to the claimed effect. The Panel considers that no conclusions could be drawn for the scientific substantiation of the claimed effect.
The Panel concludes that a cause and effect relationship has not been established between the dietary intake of vitamin B12 and maintenance of normal hair.
3.6. Utrzymanie prawidłowego stanu skóry (ID 104)
A total of nine references were provided, including three textbooks, two opinions from authoritative bodies, one review and three human studies, which were unrelated to the claimed effect. The only reference referring to skin mentioned that cobalamin deficiency may also be associated with skin hyper-pigmentation (Green, 2005). The Panel considers that no conclusions can be drawn for the scientific substantiation of the claimed effect.
The Panel concludes that a cause and effect relationship has not been established between the dietary intake of vitamin B12 and maintenance of normal skin.
3.7. Utrzymanie prawidłowego stanu paznokci (ID 104)
A total of nine references were provided, including three textbooks, two opinions from authoritative bodies, one review and three human studies, which were unrelated to the claimed effect. The Panel considers that no conclusions can be drawn for the scientific substantiation of the claimed effect.
The Panel concludes that a cause and effect relationship has not been established between the dietary intake of vitamin B12 and maintenance of normal nails.
3.8. Zmniejszenie zmęczenia (ID 108)
The haematological effects of vitamin B12 deficiency are indistinguishable from those of folate deficiency. These include pallor of the skin associated with a gradual onset of the common symptoms of anaemia, such as diminished energy and exercise tolerance, fatigue, shortness of breath and palpitations (IoM, 2000).
The Panel concludes that a cause and effect relationship has been established between the dietary intake of vitamin B12 and reduction of tiredness and fatigue.
4. Uwagi do zaproponowanego brzmienia oświadczenia
4.1. Udział w prawidłowym przebiegu funkcji neurologicznych i psychicznych (psychologicznych) (ID 95, 97, 98, 100, 102, 109)
The Panel considers that the following wording reflects the scientific evidence: “Vitamin B12 contributes to normal neurological and psychological functions”.
4.2. Udział w prawidłowym metabolizmie homocysteiny (ID 96, 103, 106)
The Panel considers that the following wording reflects the scientific evidence: “Vitamin B12 contributes to normal homocysteine metabolism”.
4.3. Zmniejszenie zmęczenia (ID 108)
The Panel considers that the following wording reflects the scientific evidence: “Vitamin B12 can contribute to the reduction of tiredness and fatigue”.
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 B12 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. For vitamin B12 no adverse effects have been reported after high dose supplementation and no Tolerable Upper Intake Levels (ULs) have been set (SCF, 2000).
Wnioski
On the basis of the data presented, the Panel concludes that:
The food constituent, vitamin B12, which is the subject of the health claims is sufficiently characterised.
Contribution to normal neurological and psychological functions (ID 95, 97, 98, 100, 102, 109)
The claimed effects are “neurological system: structure and function”, “cognitive function in ageing”, “nerve system and cognitive function”, “the role of vitamins and minerals in mental performance (where mental performance stands for those aspects of brain and nerve functions which determine aspects like concentration, learning, memory and reasoning)”. The target population is assumed to be the general population. Contribution to normal neurological and psychological functions, which encompass cognitive and affective domains, is a beneficial physiological effect.
A cause and effect relationship has been established between the dietary intake of vitamin B12 and contribution to normal neurological and psychological functions.
The following wording reflects the scientific evidence: “Vitamin B12 contributes to normal neurological and psychological functions”.
Contribution to normal homocysteine metabolism (ID 96, 103, 106)
The claimed effects are “homocysteine metabolism”, “homocysteine levels”, and “heart health”. The target population is assumed to be the general population. Contribution to normal homocysteine metabolism is a beneficial physiological effect.
A cause and effect relationship has been established between the dietary intake of vitamin B12 and contribution to normal homocysteine metabolism.
The following wording reflects the scientific evidence: “Vitamin B12 contributes to normal homocysteine metabolism.”
Maintenance of normal bone (ID 104)
The claimed effect is “bone/teeth/hair/skin and nail health”. The target population is assumed to be the general population. Maintenance of normal bone is a beneficial physiological effect.
A cause and effect relationship has not been established between the dietary intake of vitamin B12 and maintenance of normal bone.
Maintenance of normal teeth (ID 104)
The claimed effect is “bone/teeth/hair/skin and nail health”. The target population is assumed to be the general population. Maintenance of normal teeth is a beneficial physiological effect.
A cause and effect relationship has not been established between the dietary intake of vitamin B12 and maintenance of normal teeth.
Maintenance of normal hair (ID 104)
The claimed effect is “bone/teeth/hair/skin and nail health”. The target population is assumed to be the general population. Maintenance of normal hair is a beneficial physiological effect.
A cause and effect relationship has not been established between the dietary intake of vitamin B12 and maintenance of normal hair.
Maintenance of normal skin (ID 104)
The claimed effect is “bone/teeth/hair/skin and nail health”. The target population is assumed to be the general population. Maintenance of normal skin is a beneficial physiological effect.
A cause and effect relationship has not been established between the dietary intake of vitamin B12 and maintenance of normal skin.
Maintenance of normal nails (ID 104)
The claimed effect is “bone/teeth/hair/skin and nail health”. The target population is assumed to be the general population. Maintenance of normal nails is a beneficial physiological effect.
A cause and effect relationship has not been established between the dietary intake of vitamin B12 and maintenance of normal nails.
Reduction of tiredness and fatigue (ID 108)
The claimed effect is “vitamin/mineral supplementation to reduce fatigue and tiredness in situations of inadequate micronutrient status”. The target population is assumed to be the general population. Reduction of tiredness and fatigue is a beneficial physiological effect.
A cause and effect relationship has been established between the dietary intake of vitamin B12 and reduction of tiredness and fatigue.
The following wording reflects the scientific evidence: “Vitamin B12 can contribute to the reduction of tiredness and fatigue.”
Cell division (ID 212)
The claimed effect is “supports folic acid metabolism, in succession: DNA synthesis”. The target population is assumed to be the general population.
A claim on vitamin B12 and normal cell division has already been assessed with a favourable outcome.
Conditions and possible restrictions of use
In order to bear the claims a food should be at least a source of vitamin B12 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.