Scientific Opinion on the substantiation of health claims related to
alpha-cylcodextrin and reduction of post-prandial glycaemic responses
(ID 856, 2926), maintenance or achievement of a normal body weight
(ID 2925) 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:
Alpha-cyclodextrin
body weight
glycaemic response
health claims
1. Charakterystyka żywności / składnika
The food that is the subject of the health claims is alpha-cyclodextrin. Alpha-cyclodextrin (cyclohexaamylose or cyclomaltohexaose) is a cyclic saccharide comprised of six glucose units linked by alpha-1,4 bonds. It is produced by the action of cyclodextrin glucosyltransferase on hydrolysed starch syrups. The annular structure of alpha-cyclodextrin provides a hydrophobic cavity that allows
formation of inclusion complexes with a variety of non-polar organic molecules of appropriate size. The hydrophilic nature of the outer surface of the cyclic structure makes alpha-cyclodextrin water- soluble. Human salivary and pancreatic amylases cannot hydrolyse alpha-cyclodextrin to a significant extent, but alpha-cyclodextrin can be hydrolysed by alpha-amylases of bacterial origin in the human intestine. Alpha–cyclodextrin is considered a soluble dietary fibre.
The Panel considers that the food constituent, alpha-cyclodextrin, which is the subject of the health claims is sufficiently characterised.
2. Znaczenie oświadczenia dla zdrowia człowieka
2.1. Zmniejszenie stężenia glukozy we krwi po posiłku (ID 856, 2926)
The claimed effect is “glucose homeostasis”. The Panel assumes that the target population is subjects willing to reduce their post-prandial glycaemic responses.
In the context of the proposed wordings, the Panel assumes that the claimed effect refers to the reduction of post-prandial glycaemic and insulinaemic 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 that varies in magnitude and duration and 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). The evidence provided does not establish that decreasing post-prandial glycaemic responses in subjects with normal glucose tolerance is a beneficial physiological effect. However, it may be beneficial to subjects 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 may be a beneficial physiological effect.
2.2. Osiąganie lub utrzymywanie prawidłowej masy ciała (ID 2925)
The claimed effect is “weight management”. The Panel assumes that the target population is the general population.
Weight management can be interpreted as the contribution to the maintenance of a normal body weight. In this context even a moderate weight loss in overweight subjects without achieving a normal body weight is considered beneficial to health.
The Panel considers that the maintenance or achievement of a normal body weight is a beneficial physiological effect.
3. Naukowe uzasadnienia wpływu na zdrowie człowieka
3.1. Zmniejszenie stężenia glukozy we krwi po posiłku (ID 856, 2926)
Two references were submitted in relation to this claim. One is an unpublished project report which only contains the description of a study but not the results.
The second reference describes a double-blind randomised crossover human intervention study in 10 healthy subjects (Buckley et al., 2006). Subjects (five females) consumed boiled white rice with 50g
of digestible carbohydrates to which 0, 2, 5 or 10g of alpha-cyclodextrin was added. Glucose and insulin were measured over a 2h period after the ingestion of each meal. The incremental area under the curve for the glucose response was significantly lower for the boiled white rice to which 5 or 10g alpha-cyclodextrin was added compared to the control rice (without alpha-cyclodextrin). No effect on post-prandial serum insulin concentrations was observed for either dose of alpha-cyclodextrin.
In weighing the evidence the Panel took into account that only one study was presented testing the effects of alpha-cyclodextrin on post-prandial blood glucose responses when added to white rice (Buckley et al., 2006) without accompanying evidence of a biologically plausible mechanism by which alpha-cyclodextrin could exert the claimed effect.
The Panel concludes that the evidence provided is insufficient to establish a cause and effect relationship between the consumption of alpha-cyclodextrin and the reduction of post-prandial glycaemic responses.
3.2. Osiąganie lub utrzymywanie prawidłowej masy ciała (ID 2925)
Among the four references provided, one full article and one abstract investigated the effects of alpha- cyclodextrin on health outcomes unrelated to the claimed effect (e.g., blood lipids, faecal excretion of saturated fat). The Panel considers that no conclusions can be drawn from this study for the substantiation of the claimed effect.
One human study and one animal study investigating the effects of alpha-cyclodextrin on body weight were submitted.
Grunberger et al. (2007) report the results from a randomised controlled trial in which 60 obese adults of both sexes on pharmacological treatment for type 2 diabetes were randomised to consume either placebo tablets (6 tablets/d, 1g tablet per fat-containing meal) or tablets containing alpha-cyclodextrin (6 tablets/d, 1g tablet per fat-containing meal) for 12 weeks. A total of 47 subjects completed the intervention and entered data analysis (controls n = 27). The placebo group gained on average 1.54 kg over 12 weeks, whereas the supplemented group gained 0.27 kg. This difference was only statistically significant after adjusting for energy intake, which was largest in the supplemented group.
Also a 6-week rat feeding study was presented investigating the effects of alpha-cyclodextrin added to low and high fat diets on body weight (Artiss et al., 2006). The Panel notes that the results of this study do not predict an effect of alpha-cyclodextrin intake on body weight in humans.
The Panel concludes that a cause and effect relationship has not been established between the consumption of alpha-cyclodextrin and the maintenance or achievement of a normal body weight.
Wnioski
On the basis of the data presented, the Panel concludes that:
The food constituent, alpha-cyclodextrin, that is the subject of the health claims is sufficiently characterised.
Reduction of post-prandial glycaemic responses (ID 856, 2926)
The claimed effect is “glucose homeostasis”. The target population is assumed to be subjects willing to reduce their post-prandial glycaemic responses. Reduction of post-prandial glycaemic responses may be a beneficial physiological effect.
The evidence provided is insufficient to establish a cause and effect relationship between the consumption of alpha-cyclodextrin and the reduction of post-prandial glycaemic responses.
Maintenance or achievement of a normal body weight (ID 2925)
The claimed effect is “weight management”. The target population is assumed to be the general population. Maintenance or achievement of a normal body weight is a beneficial physiological effect.
A cause and effect relationship has not been established between the consumption of alpha- cyclodextrin and the maintenance or achievement of a normal body weight.