Acute Effects of the Two Alternative Sweeteners D-allulose and Erythritol on Metabolism

Plasma GLP-1 will be measured with a commercially available immunoassay kit (MILLIPLEX® MAP; Millipore Corporation, Billerica, MA, USA).

Plasma PYY, and ghrelin will be measured with a commercially available immunoassay kit (MILLIPLEX® MAP; Millipore Corporation, Billerica, MA, USA).

Plasma ghrelin will be measured with a commercially available immunoassay kit (MILLIPLEX® MAP; Millipore Corporation, Billerica, MA, USA).

Plasma cholecystokinin (CCK) levels will be measured with a sensitive radioimmunoassay using a highly specific antiserum.

Plasma motilin levels will be measured with a sensitive radioimmunoassay as previously described using 125I [Nle13] human motilin as tracer and rabbit anti-human Nle13 motilin antibody (final dilution 1/12000).

Blood glucose concentrations will be measured by a commercial hexokinase-glucose-6-phosphate-dehydrogenase method (Roche, Basel, Switzerland).

Insulin, c-peptide and glucagon will be measured with a commercially available immunoassay kit (MILLIPLEX® MAP; Millipore Corporation, Billerica, MA, USA). The lowest level of insulin that can be detected by this assay is 87 pg/mL when using a 25 µL sample. The lowest level of c-peptide that can be detected by this assay is 9.5 pg/mL when using a 25 µL sample. The lowest level of glucagon that can be detected by this assay is 13 pg/mL when using a 25 µL sample. The intra-assay coefficient of variation for all peptides (insulin, c-peptide and glucagon) is below 10%, whereas the inter-assay coefficient of variation is below 15%.

Insulin will be measured with a commercially available immunoassay kit (MILLIPLEX® MAP; Millipore Corporation, Billerica, MA, USA). The lowest level of insulin that can be detected by this assay is 87 pg/mL when using a 25 µL sample. The intra-assay coefficient of variation for insulin is below 10%, whereas the inter-assay coefficient of variation is below 15%.

C-peptide will be measured with a commercially available immunoassay kit (MILLIPLEX® MAP; Millipore Corporation, Billerica, MA, USA). The lowest level of c-peptide that can be detected by this assay is 9.5 pg/mL when using a 25 µL sample. The intra-assay coefficient of variation for c-peptide is below 10%, whereas the inter-assay coefficient of variation is below 15%.

Glucagon will be measured with a commercially available immunoassay kit (MILLIPLEX® MAP; Millipore Corporation, Billerica, MA, USA). The lowest level of glucagon that can be detected by this assay is 13 pg/mL when using a 25 µL sample. The intra-assay coefficient of variation for glucagon is below 10%, whereas the inter-assay coefficient of variation is below 15%.

Gastric emptying rate will be determined using a 13C-sodium acetate breath test.

Analyses of blood lipids are carried out in the hospital laboratory.

Analyses of uric acid are carried out in the hospital laboratory.

Analyses of hsCRP are carried out in the hospital laboratory.

Appetite perceptions (feelings of: a) hunger, b) satiety) are assessed by visual analogue scale (VAS). Visual analogue scales consist of a horizontal, unstructured, 10-cm line representing the minimum (0.0 points) to the maximum rating (10.0 points). Subjects assign a vertical mark across the line to indicate the magnitude of their subjective sensation at the present time point. The measurement is quantified by the distance from the left end of the line (minimum rating) to the subject's vertical mark.

GI symptoms will be assessed by use of a checklist including the following questions: abdominal pain, nausea, vomiting, diarrhoea, borborygmi, abdominal distension, eructation and increased flatus.