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Scientific Opinion on the substantiation of health claims related to sugar beet fibre and reduction of post-prandial glycaemic responses (ID 752), maintenance of normal blood glucose concentrations (ID 752), maintenance of normal blood LDL-cholesterol concentrations (ID 809), and changes in bowel function (ID 751) 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: LDL-cholesterol   Sugar beet fibre   blood glucose   bowel function   glycaemia   health claims  
ID:    751      752      809  
Produkty: Błonnik z buraków cukrowych  

1. Charakterystyka żywności / składnika

The food constituent that is the subject of the health claims is sugar beet fibre.
The term “sugar beet fibre” includes fibre derived from all plants of the species Beta vulgaris L. Sugar beet fibre contains hemicelluloses (22-32 %), pectins (22-29 %), cellulose (19-28 %), protein (5 %), ash (3 %) and moisture (7 %). The presence of both soluble and insoluble polysaccharides is roughly in a 2:1 ratio (Thibault et al., 2001). The lignin content is low.
The Panel considers that the food constituent, sugar beet fibre, which is the subject of the health claims, is sufficiently characterised in relation to the claimed effects.

2. Znaczenie oświadczenia dla zdrowia człowieka


2.1. Zmniejszenie stężenia glukozy we krwi po posiłku (ID 752)

The claimed effect is “blood glucose control; glycaemic control, glycaemic response”. The Panel assumes that the target population is individuals wishing to reduce their post-prandial glycaemic responses.
Postprandial glycaemia is interpreted as the elevation of blood glucose concentrations after consumption of a food and/or meal. This function is a normal physiological response which varies in magnitude and duration, and which may be influenced by the chemical and physical nature of the food or meal consumed, as well as by individual factors (Venn and Green, 2007). Decreasing post-prandial glycaemic responses may, for example, be beneficial to individuals with impaired glucose tolerance, as long as post-prandial insulinaemic responses are not disproportionally increased. Impaired glucose tolerance is common in the general population of adults.
The Panel considers that the reduction of post-prandial glycaemic responses (as long as post-prandial insulinaemic responses are not disproportionally increased) may be a beneficial physiological effect.

2.2. Utrzymanie prawidłowego stężenia glukozy we krwi (ID 752)

The claimed effect is “blood glucose control; glycaemic control, glycaemic response”. The Panel assumes that the target population is the general population.
In the context of the proposed wording, the Panel assumes that the claimed effect refers to the maintenance of normal blood glucose concentrations.
The Panel considers that long-term maintenance of normal blood glucose concentrations is a beneficial physiological effect.

2.3. Utrzymanie prawidłowego stężenia cholesterolu LDL we krwi (ID 809)

The claimed effect is “contributes to healthy cholesterol levels”. The Panel assumes that the target population is the general population.
In the context of the information provided, the Panel assumes that the claimed effect relates to the maintenance of normal blood LDL-cholesterol concentrations.
Low-density lipoproteins (LDL) carry cholesterol from the liver to peripheral tissues, including the arteries. Elevated LDL-cholesterol, by convention >160 mg/dL (>4.1 mmol/L), may compromise the normal structure and function of the arteries.
The Panel considers that maintenance of normal blood LDL-cholesterol concentrations is a beneficial physiological effect.

2.4. Zmiany w funkcjach jelita (ID 751)

The claimed effect is normal “bowel function”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel assumes that the claimed effect refers to changes in bowel function.
The Panel considers that changes in bowel function, such as reduced transit time, more frequent bowel movements, increased faecal bulk or softer stools, may be a beneficial physiological effect, provided these changes do not result in diarrhoea.

3. Naukowe uzasadnienia wpływu na zdrowie człowieka


3.1. Zmniejszenie stężenia glukozy we krwi po posiłku (ID 752)

The references provided included reviews and book chapters on the effects of dietary fibre in general, as well as human and animal studies on specific dietary fibres other than sugar beet fibre and/or on outcomes other than measures of glycaemic responses or glycaemic control. The latter were references on blood lipid concentrations and lipid metabolism, on plasma levels of pancreatic and gastrointestinal hormones, on bile acid excretions and on glycerol responses. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
Among the references submitted, two human intervention studies investigated the effects of sugar beet fibre on post-prandial blood glucose concentrations (Hagander et al., 1986; 1988).
In a test meal study, standardised breakfasts with or without sugar beet fibre were given in random order to nine (three female, mean age 67 years, mean BMI 29.9 kg/m2) non-insulin-dependent diabetic subjects managed with diet only (Hagander et al., 1986). The standardised breakfasts were comprised of bread, butter, cheese, milk, water and coffee or tea. Sugar beet fibre was added to the baked bread and given additionally in milk. The two breakfasts contained identical amounts of carbohydrates, protein and fat but differed in their content of dietary fibre. The sugar beet fibre breakfast contained 10.8 g of dietary fibre from sugar beet. Both breakfasts contained 4.1 g of dietary fibre from cereals. Blood glucose concentrations were monitored continuously, and insulin and other hormonal responses were determined at regular intervals for 3 h. The incremental area under the glucose curve was significantly (p<0.05) smaller after the test meal including sugar beet fibre compared with the control meal. No differences were found in the incremental areas under the curves for insulin.
In another test meal study, the same test meals as described above were given in random order to eight healthy volunteers (mean age 67.5 years, mean BMI 28.5±4.9 kg/m2) (Hagander et al., 1988). No differences between the two test meals were observed with respect to post-prandial blood glucose responses (i.e. incremental areas under the curve).
In weighing the evidence, the Panel took into account that only two small studies were provided which assessed the effects of sugar beet fibre on post-prandial blood glucose responses, with inconsistent results.
The Panel concludes that a cause and effect relationship has not been established between the consumption of sugar beet fibre and reduction of post-prandial glycaemic responses.

3.2. Utrzymanie prawidłowego stężenia glukozy we krwi (ID 752)

The references provided included reviews and book chapters on the effects of dietary fibre in general, as well as human and animal studies on specific dietary fibres other than sugar beet fibre and/or on outcomes other than measures of glycaemic control. The latter were references on the effects of sugar beet fibre on post-prandial blood glucose responses, on blood lipid concentrations and lipid metabolism, on plasma levels of pancreatic and gastrointestinal hormones, and on excretion of bile acid. 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 consumption of sugar beet fibre and maintenance of normal blood glucose concentrations.

3.3. Utrzymanie prawidłowego stężenia cholesterolu LDL we krwi (ID 809)

The references provided included reviews and book chapters on the effects of dietary fibre in general, as well as human and animal studies on specific dietary fibres other than sugar beet fibre and/or on outcomes other than measures of blood cholesterol concentrations. The latter were references on the effects of sugar beet fibre on constipation, colonic function, management of the metabolic syndrome, and bowel function. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
Three human intervention studies were presented for the substantiation of this claim.
Israelsson et al. (1993) conducted a placebo-controlled, cross-over study in 30 hypercholesterolaemic women who consumed 30 g/day of sugar beet fibre or placebo for four weeks each in a random order after a one-month run-in period in the context of a moderate low-fat, low-cholesterol diet. Sugar-beet and placebo supplements (containing 3.5 % fibre by weight) were administered either as crumbs or as bread in the context of meals in 5 g portions, each containing 3 g of sugar-beet fibre in the
intervention. A significant reduction in LDL-cholesterol concentrations (-6.5 %) and in the LDL/HDL cholesterol ratio (-13.5 %) was observed during the sugar beet fibre intervention compared to placebo.
Cossack and Musaiger (1991) studied 10 desert nomads who, after a baseline period of two weeks, consumed 36 g/day of sugar beet fibre for five weeks, followed by a second baseline period of four weeks. The Panel considers that no conclusions can be drawn from this uncontrolled study for the scientific substantiation of the claimed effect.
In a placebo-controlled, randomised cross-over study, 12 patients with type 2 diabetes consumed sugar beet fibre (40 g/day) or placebo for eight weeks each (Hagander et al., 1989). No significant differences on total or LDL-cholesterol concentrations were observed between the sugar beet fibre and the placebo interventions during the study. The Panel notes the small number of subjects included in this study.
Sugar-beet fibre contains 22-29 % pectins by weight. The blood cholesterol-lowering effect observed in the study by Israelsson et al. (1993), where 30 g/day of sugar beet fibre were consumed daily (containing about 6 g/day of pectins), is in the range of what could be expected from the consumption of 6 g/day of pectins. As for other water-soluble fibres, the effect of pectins on blood (LDL-) cholesterol concentrations is likely to depend on its viscosity, which reduces the reabsorption of bile acids, increases the synthesis of bile acids from cholesterol, and reduces circulating blood cholesterol concentrations. The remaining fibre components in sugar-beet fibre (hemicellulose, cellulose) are non-viscous and insoluble, and are not expected to exert a cholesterol-lowering effect.
The Panel concludes that a cause and effect relationship has not been established between the consumption of sugar beet fibre and maintenance of normal blood LDL-cholesterol concentrations beyond the hypocholesterolaemic effects which could be expected from the pectin content of sugar beet fibre.
A claim on pectins and maintenance of normal blood cholesterol concentrations has already been assessed with a favourable outcome (EFSA Panel on Dietetic Products Nutrition and Allergies (NDA), 2010).

3.4. Zmiany w funkcjach jelita (ID 751)

The references provided consisted of a number of human, animal and in vitro studies that were either unrelated to the food constituent which is the subject of the health claim, addressed outcomes unrelated to the claimed effect, such as lipid or carbohydrate metabolism, or measured cholesterol and acid bile excretion in ileostomy patients. 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 consumption of sugar beet fibre and changes in bowel function.

Wnioski

On the basis of the data presented, the Panel concludes that:
The food constituent, sugar beet fibre, which is the subject of the health claims, is sufficiently characterised in relation to the claimed effects.
Reduction of post-prandial glycaemic responses (ID 752)
The claimed effect is “blood glucose control; glycaemic control, glycaemic response”. The target population is assumed to be individuals wishing to reduce their post-prandial glycaemic responses. Reduction of post-prandial glycaemic responses (as long as post-prandial insulinaemic responses are not disproportionally increased) may be a beneficial physiological effect.
A cause and effect relationship has not been established between the consumption of sugar beet fibre and reduction of post-prandial glycaemic responses.
Maintenance of normal blood glucose concentrations (ID 752)
The claimed effects are “blood glucose control; glycaemic control, glycaemic response”. The target population is assumed to be the general population. Long-term maintenance of normal blood glucose concentrations is a beneficial physiological effect.
A cause and effect relationship has not been established between the consumption of sugar beet fibre and maintenance of normal blood glucose concentrations.
Maintenance of normal blood LDL-cholesterol concentrations (ID 809)
The claimed effect is “contributes to healthy cholesterol levels”. The target population is assumed to be the general population. Maintenance of normal blood LDL-cholesterol concentrations is a beneficial physiological effect.
A cause and effect relationship has not been established between the consumption of sugar beet fibre and maintenance of normal blood LDL-cholesterol concentrations beyond the hypocholesterolaemic effects which could be expected from the pectin content of sugar beet fibre.
A claim on pectins and maintenance of normal blood cholesterol concentrations has already been assessed with a favourable outcome.
Changes in bowel function (ID 751)
The claimed effect is normal “bowel function”. The target population is assumed to be the general population. Changes in bowel function, such as reduced transit time, more frequent bowel movements, increased faecal bulk or softer stools, may be a beneficial physiological effect, provided these changes do not result in diarrhoea.
A cause and effect relationship has not been established between the consumption of sugar beet fibre and changes in bowel function.