Scientific Opinion on the substantiation of health claims related to biotin
and maintenance of normal skin and mucous membranes (ID 121),
maintenance of normal hair (ID 121), maintenance of normal bone
(ID 121), maintenance of normal teeth (ID 121), maintenance of normal
nails (ID 121, 2877), reduction of tiredness and fatigue (ID 119),
contribution to normal psychological functions (ID 120) and contribution
to normal macronutrient metabolism (ID 4661) 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:
Biotin
bone
fatigue
hair
health claims
macronutrient metabolism
mucous membranes
nail
psychological functions
skin
teeth
tiredness
1. Charakterystyka żywności / składnika
The food constituent that is the subject of the health claims is biotin, which is a well recognised nutrient and is measurable in foods by established methods. Biotin occurs naturally in foods as free biotin and in protein bound forms; there are eight stereoisomers, but D(+)-biotin is the only naturally occurring isomer that plays a role in human metabolism, and currently the only form authorised for addition to foods (Annex II of the Regulation (EC) No 1925/20066 and Annex II of Directive 2002/46/EC7). This evaluation applies to biotin 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, biotin, which is the subject of the health claims, is sufficiently characterised.
2. Znaczenie oświadczenia dla zdrowia człowieka
2.1. Utrzymanie prawidłowego stanu skóry i błon śluzowych (ID 121)
The claimed effect is “bone/teeth/hair/skin and nail health”. The Panel assumes that the target population is the general population.
A claim on biotin and maintenance of normal skin and mucous membranes has already been assessed with a favourable outcome (EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA), 2009).
2.2. Utrzymanie prawidłowego stanu włosów (ID 121)
The claimed effect is “bone/teeth/hair/skin and nail health”. The Panel assumes that the target population is the general population.
A claim on biotin and maintenance of normal hair has already been assessed with a favourable outcome (EFSA Panel on Dietetic Products Nutrition and Allergies (NDA), 2009).
2.3. Utrzymanie prawidłowego stanu kości (ID 121)
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 121)
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 the maintenance of normal teeth is a beneficial physiological effect.
2.5. Utrzymanie prawidłowego stanu paznokci (ID 121, 2877)
The claimed effects are “bone/teeth/hair/skin and nail health” and “resistance and strength of nails”. The Panel assumes that the target population is the general population.
The Panel considers that maintenance of normal nails is a beneficial physiological effect.
2.6. Zmniejszenie zmęczenia (ID 119)
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.
2.7. Udział w prawidłowym przebiegu funkcji psychicznych (psychologicznych) (ID 120)
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.
The Panel considers that contribution to normal psychological functions, which encompass cognitive and affective domains, is a beneficial physiological effect.
2.8. Udział w prawidłowym metabolizmie makroskładników (ID 4661)
The claimed effect is “role in protein and amino acid metabolism”. The Panel assumes that the target population is the general population.
Protein and amino acid metabolism is part of normal macronutrient metabolism.
The Panel considers that the claimed effect is related to macronutrient metabolism.
A claim on biotin and normal macronutrient metabolism 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 -
It is well established that biotin is a cofactor for the acetyl-CoA, propionyl-CoA, ß-methylcrotonyl- CoA and pyruvate carboxylase enzymes, which are important in the synthesis of fatty acids, the catabolism of some branched-chain amino acids and for the gluconeogenic pathway.
Pyruvate carboxylase catalyses the carboxylation of pyruvate to form oxaloacetate which, in turn, serves as an intermediate in gluconeogenesis as well as in the citric acid cycle.
Methylcrotonyl-CoA carboxylase is required for the degradation of leucine, a branched-chain amino acid.
Acetyl-CoA carboxylase catalyses the carboxylation of acetyl-CoA to malonyl-CoA which, in turn, serves as a substrate for fatty acid elongation.
Propionyl-CoA carboxylase carboxylates propionyl-CoA to form D-methylmalonyl-CoA which is epimerised to the L-isomer and then transformed to succinyl-CoA, which then enters the citric acid cycle. The metabolic pathway from propionyl-CoA to succinyl-CoA is also part of the oxidation of fatty acids with an odd number of carbon atoms where the final cleavage forms acetyl-CoA and propionyl-CoA. This pathway is also involved in the catabolism of the branched-chain amino acids isoleucine and valine as well as the amino acids methionine and threonine (IoM, 1998; Stryer, 1988).
Biotin may also have a role in the regulation of gene expression arising from its interaction with nuclear histone proteins (EVM, 2003).
Biotin deficiency only appears after weeks to several years of raw egg-white feeding or biotin-free parenteral nutrition. Thinning of hair and progression to loss of all hair, including eyebrows and lashes, has been reported. A scaly (seborrhoeic), red (eczematous) skin rash was present in the majority; in several, the rash was distributed around the eyes, nose, mouth, and perineal orifices. Depression, lethargy, hallucinations, and paraesthesia of the extremities were prominent neurological symptoms in the majority of adults. The most striking neurological findings in infants were hypotonia, lethargy, and developmental delay (Mock, 2005).
3.1. Utrzymanie prawidłowego stanu kości (ID 121)
A total of 21 references were cited to substantiate the claim. 13 were textbooks or opinions from scientific bodies in which the claimed effect was not stated. Seven references dealt with outcomes unrelated to the claimed effect, such as the effect of biotin on skin, hair and nails. One reference was related to biotin deficiency in animals. The Panel considers that no conclusions could be drawn from these references for the scientific substantiation of the claimed effect.
The Panel notes that bone disorders are not among the symptoms of biotin deficiency in humans.
The Panel concludes that a cause and effect relationship has not been established between the dietary intake of biotin and the maintenance of normal bone.
3.2. Utrzymanie prawidłowego stanu zębów (ID 121)
A total of 21 references were cited to substantiate the claim. 13 were textbooks or opinions from scientific bodies in which the claimed effect was not stated. Seven references dealt with outcomes unrelated to the claimed effect, such as the effect of biotin on skin, hair and nails. One reference was related to biotin deficiency in animals. The Panel considers that no conclusions could 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 biotin and the maintenance of normal of teeth.
3.3. Utrzymanie prawidłowego stanu paznokci (ID 121, 2877)
A total of 23 references were cited to substantiate the claimed effect of which 13 were textbooks or opinions of scientific bodies in which the claimed effect was not stated and five were references related to other health effects. The Panel considers that no conclusions could be drawn from these references for the scientific substantiation of the claimed effect.
Five references described human studies which examined the effect of biotin supplementation on brittle fingernails.
Three uncontrolled, non-blinded studies were provided in which (a) women with nail hardness disorders were given 2.5 mg biotin daily for six to 10 months and nail quality was assessed by subject interview (Floersheim, 1989), (b) adolescents and adults with alopecia and nail quality disorders were given 2.5 mg biotin daily for six to 15 months and nail quality was assessed by subjective reporting (Floersheim, 1992), and (c) adults diagnosed with nail splitting or brittle nails were given 1 to 3 mg biotin daily for 1.5 to 7 months and nail quality was assessed using a questionnaire sent to patients and telephone survey (Hochman et al., 1993). The Panel notes that these studies were not blinded, did not control for factors other than biotin that might have influenced the outcome, that no objective methods were used to determine changes in nail quality, and the doses studied were considerably higher than the ones proposed in the conditions of use, all of which limit the value of the studies as a source of data. As a follow-up to the Floersheim study (1989), nail thickness was assessed using scanning electron microscopy in women with brittle nails of unknown aetiology (excluding women with a specific diagnosis of a nail dystrophy) given 2.5 mg biotin daily for six to 15 months (Colombo et al., 1990). The Panel notes that the study was not blinded, did not control for factors other than biotin that might have influenced the outcome, and that the dose studied was considerably higher than the ones proposed in the conditions of use, all of which limit the value of the study as a source of data.
A double-blind placebo controlled intervention (Gehring, 1996) included 60 subjects with reduced nail quality randomly assigned to consume either placebo (n=30) or 2.5 mg of biotin (n=30) daily for six months. Inclusion criteria were adults above 18 years of age with brittle, splintered or soft nails of unknown origin. Exclusion criteria were known nail disorders, such as mycosis, psoriasis and Lichen ruber, pregnancy, severe neurological, mental or internal disorders, biotin deficiency, concurrent medication and participation in other studies less then four weeks prior to the start of the intervention. Three subjects in each group were excluded from statistical analysis for different reasons. The swelling behaviour of nail keratin after incubation with sodium hydroxide (NaOH) and transonychial water loss were measured after three and six months. The Panel considers that the evidence provided does not establish that these assays are appropriate measures of nail quality. In addition, clinical judgement by the investigator and the subject was used. The Panel notes that no information was provided on the nature of the clinical examination carried out by the investigator or on the aspects of nail quality considered by the subjects, and that the dose studied was considerably higher than the doses proposed in the conditions of use, all of which limit the value of the study as a source of data.
In weighing the evidence, the Panel took into account that all but one of the studies were not blinded and did not control for factors other than biotin that might have influenced the outcome, that in three of the five studies no objective methods to determine changes in nail quality were used, that the evidence provided in the remaining study did not establish that the endpoints used in this study are appropriate measures of nail quality and that in all studies the doses studied were considerably higher than the ones proposed in the conditions of use.
The Panel concludes that a cause and effect relationship has not been established between the dietary intake of biotin and maintenance of normal nails.
3.4. Zmniejszenie zmęczenia (ID 119)
Four references were cited to substantiate the claim. Three were textbooks in which the claimed effect was not mentioned. One was a review on the role of B-vitamins in mitochondrial energy metabolism in which the claimed effect was not mentioned. The Panel considers that no conclusions could be drawn from these references for the scientific substantiation of the claimed effect.
Fatigue is also not among the symptoms of biotin deficiency (Mock, 2005).
The Panel concludes that a cause and effect relationship has not been established between the dietary intake of biotin and the reduction of tiredness and fatigue.
3.5. Udział w prawidłowym przebiegu funkcji psychicznych (psychologicznych) (ID 120)
Depression is among the neurological symptoms of biotin deficiency observed in adults (Mock, 2005). In biotin-deficient infants, developmental delay, along with peculiar withdrawn behaviour, are characteristic of a neurological disorder resulting from lack of biotin (IoM, 1998).
The Panel concludes that a cause and effect relationship has been established between the dietary intake of biotin and contribution to normal psychological functions.
4. Uwagi do zaproponowanego brzmienia oświadczenia
4.1. Udział w prawidłowym przebiegu funkcji psychicznych (psychologicznych) (ID 120)
The Panel considers that the following wording reflects the scientific evidence: “Biotin contributes to normal psychological functions.”
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 biotin 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.
Wnioski
On the basis of the data presented, the Panel concludes that:
The food constituent, biotin, which is the subject of the health claims is sufficiently characterised.
Maintenance of normal skin and mucous membranes (ID 121)
The claimed effect is “bone/teeth/hair/skin and nail health”. The target population is assumed to be the general population.
A claim on biotin and maintenance of normal skin and mucous membranes has already been assessed with a favourable outcome.
Maintenance of normal hair (ID 121)
The claimed effect is “bone/teeth/hair/skin and nail health”. The target population is assumed to be the general population.
A claim on biotin and maintenance of normal hair has already been assessed with a favourable outcome.
Maintenance of normal bone (ID 121)
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 biotin and the maintenance of normal bone.
Maintenance of normal teeth (ID 121)
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 biotin and the maintenance of normal teeth.
Maintenance of normal nails (ID 121, 2877)
The claimed effect is “bone/teeth/hair/skin and nail health” and “resistance and strength of nails”. 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 biotin and the maintenance of normal nails.
Reduction of tiredness and fatigue (ID 119)
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 not been established between the dietary intake of biotin and the reduction of tiredness and fatigue.
Contribution to normal psychological functions (ID 120)
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 biotin and contribution to normal psychological functions.
The following wording reflects the scientific evidence: “Biotin contributes to normal psychological functions”.
Contribution to normal macronutrient metabolism (ID 4661)
The claimed effect is “role in protein and amino acid metabolism”. The target population is assumed to be the general population.
A claim on biotin and macronutrient metabolism 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 biotin 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.
