Scientific Opinion on the substantiation of health claims related to calcium
and maintenance of bones and teeth (ID 224, 230, 231, 354, 3099), muscle
function and neurotransmission (ID 226, 227, 230, 235), blood coagulation
(ID 230, 236), energy-yielding metabolism (ID 234), function of digestive
enzymes (ID 355), and maintenance of normal blood pressure (ID 225, 385,
1419) pursuant to Article 13(1) of Regulation (EC) No 1924/2006[sup]1[/sup]
EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA)2
European Food Safety Authority (EFSA), Parma, Italy
Słowa kluczowe:
Calcium
blood pressure
bones
colorectal cells
digestive enzymes
health claims
mineralisation
muscle
neurotransmission
teeth
1. Charakterystyka żywności / składnika
The food constituent that is the subject of the health claim is calcium, which is a well recognised nutrient and is measurable in foods by established methods. Calcium occurs naturally in foods in many forms which are generally well utilised by the body. Different forms of calcium are authorised for addition to foods and for use in food supplements (Annex II of the Regulation (EC) No 1925/20064 and Annex II of Directive 2002/46/EC5). This evaluation applies to calcium naturally present in foods and those forms authorised for addition to foods and for use in food supplements (Annex II of the Regulation (EC) No 1925/2006 and Annex II of Directive 2002/46/EC).
The Panel considers that the food constituent, calcium, which is the subject of the health claims, is sufficiently characterised.
2. Znaczenie oświadczenia dla zdrowia człowieka
2.1. Utrzymanie prawidłowego stanu kości i zębów (ID 224, 230, 231, 354, 3099)
The claimed effects are “bone health”, “bone strength (includes bone structure, bone mineralisation, bone density)”, “structure of teeth”, “bones and teeth” and “dental health”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel notes that the claimed effects relate to the maintenance of normal bones and teeth.
The Panel considers that the maintenance of normal bones and teeth is beneficial to human health.
2.2. Funkcje mięśni i przewodnictwo nerwowe (ID 226, 227, 230, 235)
The claimed effects are “muscle function”, “nerve transmission/function”, “nerves and muscle”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel notes that the claimed effects relate to normal muscle function and neurotransmission.
The Panel considers that normal muscle function and neurotransmission are beneficial to human health.
2.3. Krzepnięcie krwi (ID 230, 236)
The claimed effect is “needed for normal blood coagulation (blood clotting)”. The Panel assumes that the target population is the general population.
The Panel considers that normal blood coagulation is beneficial to human health.
2.4. Metabolizm energetyczny (ID 234)
The claimed effect is “energy metabolism”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel notes that the claimed effect relates to the conversion of energy from foods into energy in the form of ATP which may be readily used by the body.
The Panel considers that normal energy-yielding metabolism is beneficial to human health.
2.5. Funkcjonowanie enzymów trawiennych (ID 355)
The claimed effect is “support the normal functioning of digestion enzymes”. The Panel assumes that the target population is the general population.
Digestive enzymes are protein molecules that catalyse the breakdown of large food molecules into smaller molecules to facilitate their absorption by the small intestine. They are secreted by the salivary glands, the glands in the stomach, the pancreas, and the glands in the small intestine. Failure to digest and absorb dietary nutrients leads to malabsorption.
The Panel considers that the normal function of digestive enzymes is beneficial to human health.
2.6. Utrzymanie prawidłowego ciśnienia tętniczego (ID 225, 385, 1419)
The claimed effects are “blood pressure”, “cardiovascular system” and “healthy heart”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel notes that the claimed effect relates to the maintenance of a normal blood pressure.
Blood pressure (BP) is the pressure (force per unit area) exerted by circulating blood on the walls of blood vessels. Elevated BP, by convention above 140mmHg (systolic) and/or 90mmHg (diastolic), may compromise the normal function of the arteries.
The Panel considers that maintaining a normal blood pressure is beneficial to human health.
3. Naukowe uzasadnienia wpływu na zdrowie człowieka -
More than 99% of the total calcium in the body is located in bones and teeth and contributes to their mass, structure and strength. Besides this structural role, calcium acts as an intracellular messenger and as a cofactor for extracellular enzymes and proteins (IoM, 1997).
3.1. Utrzymanie prawidłowego stanu kości i zębów (ID 224, 230, 231, 354, 3099)
The evidence provided by consensus opinions/reports from authoritative bodies and reviews shows that there is good consensus on the roles of calcium in the maintenance of normal bones and teeth.
Calcium is an important structural component of bone and teeth. Adequate calcium intake throughout childhood and adolescence is needed to achieve maximum peak bone mass in young adulthood which is an important determinant of bone mineral status in later life. The growth, development and maintenance of bone and teeth is related to the quantity of dietary calcium consumed and recommended intakes of calcium to meet requirements for growth, development and maintenance of bone at all ages have been established by various authorities. Inadequate dietary calcium intake may contribute to impaired bone development in early life and to the accelerated loss of bone mass in adults and in older people. Available evidence indicates that calcium intakes may be inadequate in sub-groups of the population in some EU countries, especially children, women and older people (AAP, 1999; AFSSA, 2001; Branca, 1997; COMA, 1991; DGE, 2000; Elmadfa and Weichselbaum, 2004; FAO/WHO, 2001; FNB, 1999; Food Safety Authority of Ireland, 1999; Greer, 2006; JHCI, 2003; IoM, 1997, National Health and Medical Research Council, 2006; Nordic Council of Ministers, 2004; SCF, 2003; Theobald, 2005; WHO, 2003).
The Panel considers that a cause and effect relationship has been established between the dietary intake of calcium and the maintenance of normal bones and teeth.
3.2. Funkcje mięśni i przewodnictwo nerwowe (ID 226, 227, 230, 235)
The evidence provided by consensus opinions/reports from authoritative bodies and reviews shows that there is good consensus on the role of calcium in muscle function and neurotransmission (IoM, 1997; JHCI, 2003).
Normal muscle function (including the heart) and neurotransmission require adequate calcium concentrations within the cells and in the extracellular fluid (ECF). Serum calcium, which is in exchange with ECF and intracellular calcium, is tightly regulated by homeostatic mechanisms and largely independent of dietary intake. In the absence of disease, serum, ECF and intracellular calcium concentrations are virtually never low because of dietary calcium deficiency. This is because the very large calcium reserve in the skeleton prevents significant decreases of calcium in serum, ECF and intracellularly practically without limit (Weaver and Heaney, 2006).
The Panel considers that a cause and effect relationship has been established between calcium and normal muscle function and neurotransmission. However, the evidence provided does not establish that inadequate intake of calcium leading to impaired muscle function and neurotransmission occurs in the general EU population.
3.3. Krzepnięcie krwi (ID 230, 236)
The evidence provided by consensus opinions/reports from authoritative bodies and reviews shows that there is good consensus on the role of calcium in normal blood coagulation.
Calcium is necessary to stabilise or allow maximal activity for a number of blood clotting enzymes. However, the normal activity of these enzymes is not significantly affected by changes in extracellular calcium concentrations or by dietary calcium deficiency, and is practically independent of dietary calcium intake (Weaver and Heaney, 2006).
The Panel considers that a cause and effect relationship has been established between calcium and normal blood coagulation. However, the evidence provided does not establish that inadequate intake of calcium leading to impaired blood coagulation occurs in the general EU population.
3.4. Metabolizm energetyczny (ID 234)
The evidence provided by consensus opinions/reports from authoritative bodies and reviews shows that there is good consensus on the role of calcium in the stabilisation and activity of certain enzymes involved in energy metabolism, such as glyceraldehyde phosphate dehydrogenase, pyruvate
dehydrogenase, and -ketoglutarate dehydrogenase. However, the normal activity of these enzymes is not significantly affected by changes in extracellular calcium concentrations or by dietary calcium deficiency, and is practically independent of dietary calcium intake (Weaver and Heaney, 2006).
The Panel considers that a cause and effect relationship has been established between calcium and normal energy-yielding metabolism. However, the evidence provided does not establish that inadequate intake of calcium leading to impaired energy-yielding metabolism occurs in the general EU population.
3.5. Funkcjonowanie enzymów trawiennych (ID 355)
The list of references provided consists of one review, one report, one manual and one book chapter.
The information included in well-recognised monographs and manuals does not support a role for dietary calcium in the function of several enzymes, since such functions are not affected by changes in plasma concentrations of calcium or by dietary calcium intake (Berdanier et al., 2002; British Nutrition Foundation Taskforce, 1989; Gurr et al., 1999; EVM, 2002; Bowman and Russell, 2007; Gibney et al., 2002; Caballero et al., 2005). However, several digestive enzymes (e.g. lipase) require a chemical association between calcium and enzyme protein(s) for full catalytic activity to occur.
The Panel concludes that a cause and effect relationship has been established between calcium and the normal function of digestive enzymes. However, the evidence provided does not establish that inadequate intake of calcium leading to impaired function of digestive enzymes occurs in the general EU population.
3.6. Utrzymanie prawidłowego ciśnienia tętniczego (ID 225, 385, 1419)
Some mechanisms have been proposed for an effect of dietary calcium on blood pressure on the basis of experimental animal models of hypertension (Hatton and McCarron, 1994).
The effects of dietary calcium intake on blood pressure have also been investigated in humans. A meta-analysis of 23 observational epidemiological studies (total of 38,950 subjects) showed a weak significant negative association between habitual calcium intake and blood pressure, i.e. -0.39 mmHg systolic and -0.34 mmHg diastolic per 100 mg of dietary calcium per day (Cappuccio et al., 1995; Birkett, 1998). In contrast, in a more recent study, dietary calcium intake was positively associated with changes in blood pressure over 8 years in 1,714 middle-aged men from the Chicago Western Electric Study (Stamler et al., 2002). The mean calcium intake in this cohort was 1,019 (SD 446) mg/d. Calcium intake was not related to blood pressure in 3,239 participants aged 55 years and over in the Rotterdam Study, except for a subgroup of hypertensive subjects where an inverse association was found (Geleijnse et al, 1996). Wang et al. (2008) examined the relationship of dietary calcium intake with incident hypertension in 28,886 US women. Daily calcium intake ranged from <558 mg (bottom quintile) to >1000 mg (upper quintile). The risk of hypertension was 11-13% lower in subjects with a calcium intake >679 mg/day. The Panel notes that results form observational studies on the relationship between dietary calcium intake and blood pressure are inconsistent.
The evidence provided by several meta-analyses of randomised controlled trials (Allender et al., 1996; Bucher et al., 1996; Griffith et al., 1999; Van Mierlo et al., 2006) indicate a small beneficial effect of calcium supplementation on blood pressure. Reductions of up to 2 mmHg systolic and 1 mmHg diastolic have been achieved with calcium doses around 1 g per day (range 400-2000 mg/d). Findings,
however, are heterogeneous with around 30% of the studies showing an increase rather than a decrease in systolic blood pressure during calcium supplementation (Van Mierlo et al., 2006). Also, the evidence provided by consensus opinions/reports from authoritative bodies and reviews shows that there is no consensus on the effects of dietary calcium on blood pressure in humans (Appel et al., 2006; Mancia et al., 2007). The American Heart Association in their scientific statement on dietary approaches to prevent and treat hypertension considered data insufficient to recommend supplemental calcium as a means to lower blood pressure (Appel et al., 2006). In 2007, the European Society of Hypertension and of the European Society of Cardiology published their joint Guidelines for the Management of Arterial Hypertension. The Committee stated that the evidence for a blood pressure lowering effect of supplemental calcium is equivocal (Mancia et al., 2007).
In weighing the evidence, the Panel took into account that the evidence contained in consensus opinions/reports from authoritative bodies and reviews is equivocal, that there is no consensus on the effects of dietary calcium on blood pressure in humans, that results form observational studies on the relationship between dietary calcium intake and blood pressure are inconsistent, and that around 30% of the intervention studies show an increase rather than a decrease in systolic blood pressure during calcium supplementation.
The Panel considers that the evidence presented is insufficient to establish a cause and effect relationship between the dietary intake of calcium and the maintenance of a normal blood pressure.
4. Uwagi do zaproponowanego brzmienia oświadczenia
4.1. Utrzymanie prawidłowego stanu kości i zębów (ID 224, 230, 231, 354, 3099)
The Panel considers that the following wordings reflect the scientific evidence: “Calcium is needed for the maintenance of normal bones and teeth”.
4.2. Funkcje mięśni i przewodnictwo nerwowe (ID 226, 227, 230, 235)
The Panel considers that the following wordings reflect the scientific evidence: “Calcium contributes to normal muscle function and neurotransmission”
4.3. Krzepnięcie krwi (ID 230, 236)
The Panel considers that the following wordings reflect the scientific evidence: “Calcium contributes to normal blood clotting”
4.4. Metabolizm energetyczny (ID 234)
The Panel considers that the following wordings reflect the scientific evidence: “Calcium contributes to normal energy metabolism”
4.5. Funkcjonowanie enzymów trawiennych (ID 355)
The Panel considers that the following wordings reflect the scientific evidence: “Calcium contributes to the normal function of digestive enzymes”
5. Warunki i możliwe ograniczenia stosowania oświadczenia
-
Wapń jest potrzebny do utrzymania prawidłowego stanu kości i zębów
-
Wapń przyczynia się do prawidłowego funkcjonowania enzymów trawiennych
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Wapń przyczynia się do prawidłowego krzepnięcia krwi
-
Wapń przyczynia się do prawidłowego metabolizmu energetycznego
-
Wapń przyczynia się do prawidłowego funkcjonowania mięśni i procesów przekazywania impulsów nerwowych (neurotransmisji)
The Panel considers that in order to bear the claim a food should be at least a source of calcium as per Annex to Regulation (EC) 1924/2006. Such amounts can be easily consumed as part of a balanced
diet. No Tolerable Upper Intake Levels (UL) have been established for calcium in children and adolescents; the UL for calcium in adults is 2500 mg/day (SCF, 2003).
Wnioski
On the basis of the data presented, the Panel concludes that:
The food constituent, calcium, which is the subject of the health claims, is sufficiently characterised.
Maintenance of bones and teeth (ID 224, 230, 231, 354, 3099)
The claimed effects are “bone health”, “bone strength (includes bone structure, bone mineralisation, bone density)”, “structure of teeth”, “bones and teeth” and “dental health”. The target population is assumed to be the general population. Maintenance of bones and teeth is beneficial to human health.
A cause and effect relationship has been established between the dietary intake of calcium and the maintenance of normal bones and teeth.
The following wording reflects the scientific evidence: “Calcium contributes to the maintenance of bones and teeth”.
Muscle function and neurotransmission (ID 226, 227, 230, 235)
The claimed effects are “muscle function”, “nerve transmission/function”, “nerves and muscle”. The target population is assumed to be the general population. Normal muscle function and neurotransmission are beneficial to human health.
A cause and effect relationship has been established between calcium and normal muscle function and neurotransmission in healthy subjects.
The evidence provided does not establish that inadequate intake of calcium leading to impaired muscle function and neurotransmission occurs in the general EU population.
The following wording reflects the scientific evidence: “Calcium contributes to normal muscle function and neurotransmission”.
Blood coagulation (ID 230, 236)
The claimed effect is “blood coagulation (blood clotting)”. The target population is assumed to be the general population. Normal blood coagulation is beneficial to human health.
A cause and effect relationship has been established between calcium and normal blood coagulation.
The evidence provided does not establish that inadequate intake of calcium leading to impaired blood coagulation occurs in the general EU population.
The following wording reflects the scientific evidence: “Calcium contributes to normal blood clotting”.
Energy-yielding metabolism (ID 234)
The claimed effect is “energy metabolism”. The target population is assumed to be the general population. Normal energy-yielding metabolism is beneficial to human health.
A cause and effect relationship has been established between calcium and normal energy- yielding metabolism.
The evidence provided does not establish that inadequate intake of calcium leading to impaired energy-yielding metabolism occurs in the general EU population.
The following wording reflects the scientific evidence: “calcium contributes to normal energy-yielding metabolism”.
Function of digestive enzymes (ID 355)
The claimed effect is “support the normal functioning of digestion enzymes”. The target population is assumed to be the general population. Normal function of digestive enzymes is beneficial to human health.
A cause and effect relationship has been established between calcium and the normal function of digestive enzymes.
The evidence provided does not establish that inadequate intake of calcium leading to impaired function of digestive enzymes occurs in the general EU population.
The following wording reflects the scientific evidence: “calcium contributes to the normal function of digestive enzymes”.
Maintenance of normal blood pressure (ID 225, 385, 1419)
The claimed effects are “blood pressure”, “cardiovascular system” and “healthy heart”. The target population is assumed to be the general population. Maintenance of a normal blood pressure is beneficial to human health.
The evidence presented is insufficient to establish a cause and effect relationship between the dietary intake of calcium and the maintenance of a normal blood pressure.
Conditions and possible restrictions of use
In order to bear the claim a food should be at least a source of calcium as per Annex to Regulation 1924/2006. Such amounts can be easily consumed as part of a balanced diet.