Scientific Opinion on the substantiation of health claims related to
vitamin B6 and contribution to normal homocysteine metabolism (ID 73,
76, 199), maintenance of normal bone (ID 74), maintenance of normal teeth
(ID 74), maintenance of normal hair (ID 74), maintenance of normal skin
(ID 74), maintenance of normal nails (ID 74), contribution to normal
energy-yielding metabolism (ID 75, 214), contribution to normal
psychological functions (ID 77), reduction of tiredness and fatigue (ID 78),
and contribution to normal cysteine synthesis (ID 4283) 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 B6
bone
cysteine
energy
fatigue
hair
health claims
homocysteine
metabolism
nails
psychological
skin
teeth
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. Znaczenie oświadczenia dla zdrowia człowieka
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.
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2.2. Utrzymanie prawidłowego stanu kości (ID 74)
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.
2.3. Utrzymanie prawidłowego stanu zębów (ID 74)
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.
2.4. Utrzymanie prawidłowego stanu włosów (ID 74)
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.
2.5. Utrzymanie prawidłowego stanu skóry (ID 74)
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 skin is a beneficial physiological effect.
2.6. Utrzymanie prawidłowego stanu paznokci (ID 74)
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.
2.7. Udział w prawidłowym pozyskiwaniu energii w procesach metabolicznych (ID 75, 214)
The claimed effects are “energy and vitality” and “muscle metabolism: shares in biochemical reaction which are needed for muscle contraction”. 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 effects are related to energy-yielding metabolism.
The Panel considers that contribution to normal energy-yielding metabolism is a beneficial physiological effect.
2.8. Udział w prawidłowym przebiegu funkcji psychicznych (psychologicznych) (ID 77)
The claimed effect is “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.
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The Panel considers that contribution to normal psychological functions, which encompass cognitive and affective domains, is a beneficial physiological effect.
2.9. Zmniejszenie zmęczenia (ID 78)
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 the reduction of tiredness and fatigue is a beneficial physiological effect.
2.10. Udział w prawidłowej syntezie cysteiny (ID 4283)
The claimed effect is “cystine synthesis and incorporation in keratin”. The Panel assumes that the target population is the general population.
The Panel assumes that the claimed effect relates to the synthesis of cysteine. Cysteine is a significant determinant of the tertiary structure of many proteins through a role in the formation of disulfide bonds within and between protein molecules.
The Panel considers that contribution to normal cysteine synthesis is a beneficial physiological effect.
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.
3.2. Utrzymanie prawidłowego stanu kości (ID 74)
A total of 16 references were provided, including six textbooks, two opinions of scientific bodies, one review, five human studies and two other publications. Most of the studies dealt with the role of
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homocysteine as a putative risk factor for osteoporosis. The Panel considers that no conclusions can be drawn from these references 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 B6 and maintenance of normal bone.
3.3. Utrzymanie prawidłowego stanu zębów (ID 74)
A total of 16 references were provided, including six textbooks, two opinions of scientific bodies, one review, five human studies and two other publications, on outcomes unrelated to the claimed effect. The Panel considers that no conclusions can be drawn from these references 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 B6 and maintenance of normal teeth.
3.4. Utrzymanie prawidłowego stanu włosów (ID 74)
A total of 16 references were provided, including six textbooks, two opinions of scientific bodies, one review, five human studies and two other publications, on outcomes unrelated to the claimed effect. The Panel considers that no conclusions can be drawn from these references 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 B6 and maintenance of normal hair.
3.5. Utrzymanie prawidłowego stanu skóry (ID 74)
A total of 16 references were provided, including six textbooks, two opinions of scientific bodies, one review, five human studies and two other publications. The only reference related to vitamin B6 and skin was a link to a website advising adolescents on their intake of nutrients. The Panel considers that no conclusions can be drawn from these references 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 B6 and maintenance of normal skin.
3.6. Utrzymanie prawidłowego stanu paznokci (ID 74)
A total of 16 references were provided, including six textbooks, two opinions of scientific bodies, one review, five human studies and two other publications, on outcomes unrelated to the claimed effect. The Panel considers that no conclusions can be drawn from these references 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 B6 and maintenance of normal nails.
3.7. Udział w prawidłowym pozyskiwaniu energii w procesach metabolicznych (ID 75, 214)
Vitamin B6, as PLP, plays a dual role in the provision of glucose. Glycogen phosphorylase relies on PLP as a coenzyme in the enzymatic cleavage of glycogen that sequentially releases glucose-1- phosphate units. PLP-dependent transaminases convert gluconeogenic amino acids to alpha-keto acids to create substrates for the production of glucose (Mackey et al., 2006).
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The Panel concludes that a cause and effect relationship has been established between the dietary intake of vitamin B6 and contribution to normal energy-yielding metabolism.
3.8. Udział w prawidłowym przebiegu funkcji psychicznych (psychologicznych) (ID 77)
One of the classical symptoms of vitamin B6 deficiency is confusion (IoM, 2000), implying impairment of normal psychological functions.
The Panel concludes that a cause and effect relationship has been established between the dietary intake of vitamin B6 and contribution to normal psychological functions.
3.9. Zmniejszenie zmęczenia (ID 78)
Chronic vitamin B6 deficiency can cause microcytic, hypochromic anaemia in which the haemoglobin concentration of erythrocytes is reduced (Mackey et al., 2006), which may lead to symptoms of weakness, tiredness or fatigue.
The Panel concludes that a cause and effect relationship has been established between the dietary intake of vitamin B6 and a reduction of tiredness and fatigue.
3.10. Udział w prawidłowej syntezie cysteiny (ID 4283)
The SH group in cysteine derives from methionine whilst the carbon skeleton comes from serine. Both the synthesis of cystathionine from homocysteine and serine and the splitting of cystathionine to release cysteine are catalysed by PLP dependent enzymes.
The Panel concludes that a cause and effect relationship has been established between the dietary intake of vitamin B6 and contribution to normal cysteine synthesis.
4. Uwagi do zaproponowanego brzmienia oświadczenia
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”.
4.2. Udział w prawidłowym pozyskiwaniu energii w procesach metabolicznych (ID 75, 214)
The Panel considers that the following wording reflects the scientific evidence: “Vitamin B6 contributes to normal energy-yielding metabolism”.
4.3. Udział w prawidłowym przebiegu funkcji psychicznych (psychologicznych) (ID 77)
The Panel considers that the following wording reflects the scientific evidence: “Vitamin B6 contributes to normal psychological functions”.
4.4. Zmniejszenie zmęczenia (ID 78)
The Panel considers that the following wording reflects the scientific evidence: “Vitamin B6 can contribute to the reduction of tiredness and fatigue”.
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4.5. Udział w prawidłowej syntezie cysteiny (ID 4283)
The Panel considers that the following wording reflects the scientific evidence: “Vitamin B6 contributes to normal cysteine synthesis”.
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).
Wnioski
On the basis of the data presented, the Panel concludes that:
The food constituent, vitamin B6, which is the subject of the health claims is sufficiently characterised.
Contribution to normal homocysteine metabolism (ID 73, 76, 199)
The claimed effects are “homocysteine levels”, “homocysteine metabolism” 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 B6 and contribution to normal homocysteine metabolism.
The following wording reflects the scientific evidence: “Vitamin B6 contributes to normal homocysteine metabolism”.
Maintenance of normal bone (ID 74)
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 B6 and maintenance of normal bone.
Maintenance of normal teeth (ID 74)
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 B6 and maintenance of normal teeth.
Maintenance of normal hair (ID 74)
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 B6 and maintenance of normal hair.
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Maintenance of normal skin (ID 74)
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 B6 and maintenance of normal skin.
Maintenance of normal nails (ID 74)
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 B6 and maintenance of normal nails.
Contribution to normal energy-yielding metabolism (ID 75, 214)
The claimed effects are “energy and vitality” and “muscle metabolism: shares in biochemical reaction which are needed for muscle contraction”. The target population is assumed to be the general population. Contribution to normal energy-yielding metabolism is a beneficial physiological effect.
A cause and effect relationship has been established between the dietary intake of vitamin B6 and contribution to normal energy-yielding metabolism.
The following wording reflects the scientific evidence: “Vitamin B6 contributes to normal energy-yielding metabolism”.
Contribution to normal psychological functions (ID 77)
The claimed effect is “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 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 B6 and contribution to normal psychological functions.
The following wording reflects the scientific evidence: “Vitamin B6 contributes to normal psychological functions”.
Reduction of tiredness and fatigue (ID 78)
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 B6 and reduction of tiredness and fatigue.
The following wording reflects the scientific evidence: “Vitamin B6 can contribute to the reduction of tiredness and fatigue”.
Contribution to normal cysteine synthesis (ID 4283)
The claimed effect is “cystine synthesis and incorporation in keratin”. The target population is assumed to be the general population. Contribution to normal cysteine synthesis is a beneficial physiological effect.
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A cause and effect relationship has been established between the dietary intake of vitamin B6 and contribution to normal cysteine synthesis.
The following wording reflects the scientific evidence: “Vitamin B6 contributes to normal cysteine synthesis”.
Conditions and possible restrictions of use
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.
